[Federal Register: March 19, 2003 (Volume 68, Number 53)]
[Rules and Regulations]               
[Page 13497-13520]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[[Page 13497]]


Part III

Department of the Interior


Fish and Wildlife Service


50 CFR Part 17

Endangered and Threatened Wildlife and Plants; Determination of 
Endangered Status for the Sonoma County Distinct Population Segment of 
the California Tiger Salamander; Final Rule

[[Page 13498]]



Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AI61

Endangered and Threatened Wildlife and Plants; Determination of 
Endangered Status for the Sonoma County Distinct Population Segment of 
the California Tiger Salamander

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.


SUMMARY: We, the Fish and Wildlife Service (Service), determine 
endangered status for the Sonoma County distinct population segment 
(DPS) of the California tiger salamander (Ambystoma californiense), 
under the Endangered Species Act of 1973, as amended (Act). In Sonoma 
County, the California tiger salamander is imperiled by a variety of 
factors including habitat destruction, degradation, and fragmentation 
due to urban development, hybridization with non-native salamanders, 
inadequate regulatory mechanisms, disease, and pesticide drift. We 
listed this DPS on an emergency basis on July 22, 2002. The emergency 
designation expires on March 19, 2003. This rule is effective upon 
publication in the Federal Register, and implements the Federal 
protection and recovery provisions afforded by the Act for the Sonoma 
County DPS of the California tiger salamander. This final rule is being 
issued as a result of a settlement agreement and consent decree.

DATES: This rule is effective on March 19, 2003.

ADDRESSES: The complete file for this final rule is available for 
inspection, by appointment, during normal business hours at the 
Sacramento Fish and Wildlife Office, U.S. Fish and Wildlife Service, 
2800 Cottage Way, Suite W-2605, Sacramento, CA 95825.

FOR FURTHER INFORMATION CONTACT: David E. Wooten, Susan Moore, or Chris 
Nagano, Sacramento Fish and Wildlife Office, at the address listed 
above (telephone 916/414-6600; facsimile 916/414-6713).



    The California tiger salamander was first described as Ambystoma 
californiense by Gray in 1853, based on specimens that had been 
collected in Monterey, California (Grinnell and Camp 1917). Storer 
(1925) and Bishop (1943) also considered the California tiger 
salamander to be a distinct species. Dunn (1940), Gehlbach (1967), and 
Frost (1985) stated that the California tiger salamander was a 
subspecies of the more widespread tiger salamander (Ambystoma 
tigrinum). However, based on recent studies of the genetics, geographic 
distribution, and ecological differences among the members of the A. 
tigrinum complex, the California tiger salamander is now considered to 
be a distinct species (Shaffer and Stanley 1991; Shaffer et al. 1993; 
Jones 1993; Shaffer and McKnight 1996; Irschick and Shaffer 1997; 
Petranka 1998). The range of this animal does not naturally overlap 
with any other species of tiger salamander (Stebbins 1985; Petranka 
    The California tiger salamander is a large, stocky, terrestrial 
salamander with small eyes and a broad, rounded snout. Adults may reach 
a total length of 208 millimeters (mm) (8.2 inches (in)), with males 
generally averaging about 203 mm (8 in) in total length and females 
averaging about 173 mm (6.8 in) in total length. For both sexes, the 
average snout-vent length is approximately 91 mm (3.6 in). The small 
eyes have black irises and protrude from the head. Coloration consists 
of white or pale yellow spots or bars on a black background on the back 
and sides. The belly varies from almost uniform white or pale yellow to 
a variegated pattern of white or pale yellow and black. Males can be 
distinguished from females, especially during the breeding season, by 
their swollen cloacae (a common chamber into which the intestinal, 
urinary, and reproductive canals discharge), more developed tail fins, 
and larger overall size (Stebbins 1962; Loredo and Van Vuren 1996).
    California tiger salamanders are restricted to vernal pools and 
seasonal ponds in grassland and oak savannah plant communities from sea 
level to about 460 meters (m) (1,500 feet (ft)) (Stebbins 1989; Shaffer 
et al. 1993; Jennings and Hayes 1994; Petranka 1998; California Natural 
Diversity Data Base (CNDDB) 2002). Genetic studies of the California 
tiger salamander suggest that levels of interchange among populations 
are very low, and that populations or groups of subpopulations 
(metapopulations) are genetically isolated from one another (Shaffer et 
al. 1993; Shaffer and Trenham 2002). Studies of mitochondrial DNA and 
allozymes (proteins) indicate that there are six populations of 
Ambystoma californiense, which are found in: (1) The Santa Rosa area of 
Sonoma County; (2) the Bay Area (central and southern Alameda, Santa 
Clara, western Stanislaus, western Merced, and the majority of San 
Benito counties); (3) the Central Valley (Yolo, Sacramento, Solano, 
eastern Contra Costa, northeast Alameda, San Joaquin, Stanislaus, 
Merced, and northwestern Madera counties); (4) southern San Joaquin 
Valley (portions of Madera, central Fresno, and northern Tulare and 
Kings counties); (5) the Central Coast Range (southern Santa Cruz, 
Monterey, northern San Luis Obispo, and portions of western San Benito, 
Fresno, and Kern counties); and (6) Santa Barbara County (Shaffer and 
Trenham 2002).
    The California tiger salamander in Sonoma County inhabits low-
elevation (below 60 m (200 ft)) vernal pools and seasonal ponds, 
associated grassland, and oak savannah plant communities. The historic 
range of the species also may have included the Petaluma River 
watershed, as there is one historic record of a specimen from the 
vicinity of Petaluma from the mid-1800s (Borland 1856, as cited in 
Storer 1925).
    California tiger salamanders found in the Santa Rosa Plain in 
Sonoma County are geographically separated from other California tiger 
salamander populations. The closest California tiger salamander 
populations to Sonoma County are located in Contra Costa, Yolo, and 
Solano counties, which are separated from the Sonoma County population 
by the Coast Range, Napa River, and the Carquinez Straits, a distance 
of about 72 kilometers (km) (45 miles (mi)).
    Subadult and adult California tiger salamanders spend the dry 
summer and fall months of the year estivating (a state of dormancy or 
inactivity in response to hot, dry weather) in the burrows of small 
mammals, such as California ground squirrels (Spermophilus beecheyi) 
and Botta's pocket gopher (Thomomys bottae) (Storer 1925; Loredo and 
Van Vuren 1996; Petranka 1998; Trenham 1998a). During estivation, 
California tiger salamanders eat very little (Shaffer et al. 1993). 
Once fall or winter rains begin, they emerge from these retreats on 
rainy nights to feed and to migrate to the breeding ponds (Stebbins 
1985, 1989; Shaffer, et al. 1993). The salamanders breeding in, and 
living around, a seasonal pool or pools, and associated uplands where 
estivation can occur are said to occupy a breeding site. A breeding 
site is defined as a location where the animals are able to 
successfully breed in years of ``normal'' rainfall and complete their 
estivation (derived from Trenham 1998b and 2001). Normal rainfall in 
Santa Rosa is 76 centimeters (cm) (30 in) per year (National Weather 
Service 2002).
    Occurrence of California tiger salamanders in Sonoma County is 
significantly associated with occurrence

[[Page 13499]]

of gophers (D. Cook, The Wildlife Society, pers. comm., 2002). Active 
gopher burrows probably are needed to sustain California tiger 
salamanders because inactive burrow systems become progressively 
unsuitable over time. California tiger salamanders cannot persist 
without estivation habitat.
    Adult California tiger salamanders may migrate up to 2 km (1 mi) 
from their estivation sites to the breeding ponds (S. Sweet, University 
of California, Santa Barbara, in litt., 1998), which may be vernal 
pools, stockponds, or other seasonal water bodies. The distance between 
the estivation sites and breeding pools depends on local topography and 
vegetation, and the distribution of ground squirrel or other rodent 
burrows (Stebbins 1989; Lawrence Hunt, consultant, in litt., 1998). 
Males migrate before females (Twitty 1941; Shaffer et al. 1993; Loredo 
and Van Vuren 1996; Trenham 1998b). Males usually remain in the ponds 
for an average of about 6 to 8 weeks, while females stay for 
approximately 1 to 2 weeks. In dry years, both sexes may stay for 
shorter periods (Loredo and Van Vuren 1996; Trenham 1998b). Most marked 
salamanders have been recaptured at the pond where they were initially 
captured; in one study approximately 80 percent were recaptured at the 
same pond (Trenham 1998b). The rate of natural movement of salamanders 
among breeding sites depends on the distance between the ponds or 
complexes of ponds and on the intervening habitat (e.g., salamanders 
may move more quickly through sparsely covered and more open grassland 
than densely vegetated lands) (Trenham 1998a). As with migration 
distances, the number of ponds used by an individual over its lifetime 
will be dependent on landscape features and environmental factors.
    The adults mate in the ponds and the females lay their eggs in the 
water (Twitty 1941; Shaffer et al. 1993; Petranka 1998). Females attach 
their eggs singly, or in rare circumstances, in groups of two to four, 
to twigs, grass stems, vegetation, or debris (Storer 1925; Twitty 
1941). In ponds with no or limited vegetation, they may be attached to 
objects, such as rocks and boards on the bottom (Jennings and Hayes 
1994). After breeding, adults leave the pool and return to the small 
mammal burrows (Loredo et al. 1996; Trenham 1998a), although they may 
continue to come out nightly for approximately the next 2 weeks to feed 
(Shaffer et al. 1993). In drought years, the seasonal pools may not 
form and the adults can not breed (Barry and Shaffer 1994).
    Salamander eggs hatch in 10 to 14 days with newly hatched 
salamanders (larvae) ranging from 11.5 to 14.2 mm (0.45 to 0.55 in) in 
total length (Petranka 1998). The larvae are aquatic. They are 
yellowish gray in color and have broad fat heads, possess large, 
feathery external gills, and broad dorsal fins that extend well onto 
their back. The larvae feed on zooplankton, small crustaceans, and 
aquatic insects for about 6 weeks after hatching, after which they 
switch to larger prey (J. Anderson 1968). Larger larvae have been known 
to consume smaller tadpoles of Pacific treefrogs (Pseudacris regilla) 
and California red-legged frogs (Rana aurora) (J. Anderson 1968; P. 
Anderson 1968). The larvae are among the top aquatic predators in the 
seasonal pool ecosystems. They often rest on the bottom in shallow 
water, but also may be found at different layers in the water column in 
deeper water. The young salamanders are wary and when approached by 
potential predators will dart into vegetation on the bottom of the pool 
(Storer 1925).
    The larval stage of the California tiger salamander usually lasts 3 
to 6 months, as most seasonal ponds and pools dry up during the summer 
(Petranka 1998). Amphibian larvae must grow to a critical minimum body 
size before they can metamorphose (change into a different physical 
form) to the terrestrial stage (Wilbur and Collins 1973). Individuals 
collected near Stockton in the Central Valley during April varied from 
47 to 58 mm (1.85 to 2.3 in) in length (Storer 1925). Feaver (1971) 
found that larvae metamorphosed and left the breeding pools 60 to 94 
days after the eggs had been laid, with larvae developing faster in 
smaller, more rapidly drying pools. The longer the ponding duration, 
the larger the larvae and metamorphosed juveniles are able to grow, and 
the more likely they are to survive and reproduce (Pechmann et al. 
1989; Semlitsch et al. 1988; Morey 1998; Trenham 1998b). The larvae 
will perish if a site dries before they complete metamorphosis (P. 
Anderson 1968; Feaver 1971). Pechmann et al. (1989) found a strong 
positive correlation between ponding duration and total number of 
metamorphosing juveniles in five salamander species. In Madera County, 
Feaver (1971) found that only 11 of 30 pools sampled supported larval 
California tiger salamanders, and five of these dried before 
metamorphosis could occur. Therefore, out of the original 30 pools, 
only six (20 percent) provided suitable conditions for successful 
reproduction that year. Size at metamorphosis is positively correlated 
with stored body fat and survival of juvenile amphibians, and 
negatively correlated with age at first reproduction (Semlitsch et al. 
1988; Scott 1994; Morey 1998).
    When the metamorphosed juveniles leave their ponds in the late 
spring or early summer, before the ponds dry completely, they settle in 
small mammal burrows at the end of their nightly movements (Zeiner et 
al. 1988; Shaffer et al. 1993; Loredo et al. 1996). Like the adults, 
juveniles may emerge from these retreats to feed during nights of high 
relative humidity (Storer 1925; Shaffer et al. 1993) before settling in 
their selected estivation sites for the dry, hot summer months. 
Juveniles have been observed to migrate up to 1.6 km (1 mi) from 
breeding ponds to estivation areas (Austin and Shaffer 1992).
    An estimated 83 percent of the salamanders rely on rodent burrows 
for shelter (Petranka 1998). Mortality of juveniles during their first 
summer exceeds 50 percent (Trenham 1998b). Emergence from estivation in 
hot dry weather occasionally results in mass mortality of juveniles 
(Holland et al. 1990). Juveniles do not typically return to the 
breeding pools until they reach sexual maturity at several years of age 
(Trenham 1998b; L. Hunt, in litt., 1998). Trenham (1998b) estimated 
survival from metamorphosis to maturity at his study site at less than 
5 percent, well below the estimated replacement level of 18 percent 
that would maintain the population. Adult survivorship varies greatly 
between years, but is a crucial determinant of whether a population is 
a source or sink (i.e., whether net productivity exceeds the level 
necessary to maintain the population).
    Lifetime reproductive success for California and other tiger 
salamanders is low. Trenham et al. (2000) found the average female bred 
1.4 times and produced 8.5 young that survived to metamorphosis per 
reproductive effort. This resulted in roughly 11 metamorphic offspring 
over the lifetime of a female. Preliminary data suggest that most 
individuals of the California tiger salamanders require 2 years to 
become sexually mature, but some individuals may be slower to mature 
(Shaffer et al. 1993). Some animals do not breed until they are 4 to 6 
years old. While individuals may survive for more than 10 years, many 
breed only once, and in some populations, less than 5 percent of marked 
juveniles survive to become breeding adults (Trenham 1998b). With such 
low recruitment, isolated populations can decline greatly from unusual, 
randomly occurring natural events as well as from human caused factors 
that reduce breeding success and individual survival. Factors

[[Page 13500]]

that repeatedly lower breeding success in isolated ponds that are too 
far from other ponds for migrating individuals to replenish the 
population can quickly extirpate a population.
    The total number of individual California tiger salamanders in 
Sonoma County is not known. The difficulty of estimating total 
California tiger salamander population size has been discussed by a 
number of biologists (Shaffer et al. 1993; Jennings and Hayes 1994). 
However, estimates have been made for a few populations in Monterey 
(Barry and Shaffer 1994; Trenham et al. 1998b). Because data on numbers 
of individual California tiger salamanders are lacking since these 
amphibians spend much of their lives underground, and because only a 
portion of the total number of animals migrate to pools to breed each 
year, the availability of suitable habitat and documentation of its 
loss is thus an appropriate method for assessing the status of the 
    The life history and ecology of the California tiger salamander on 
the Santa Rosa Plain in Sonoma County make it likely that this 
population has a metapopulation structure (Hanski and Gilpin 1991). A 
metapopulation is a set of local populations or breeding sites within 
an area, where typically migration from one local population or 
breeding site to other areas containing suitable habitat is possible, 
but not routine. Movement between areas containing suitable habitat 
(i.e., dispersal) is restricted due to inhospitable conditions around 
and between areas of suitable habitat. Because many of the areas of 
suitable habitat may be small, and support small numbers of 
salamanders, local extinction of these small units may be common. A 
metapopulation's persistence depends on the combined dynamics of these 
local extinctions and the subsequent recolonization of these areas by 
dispersal (Hanski and Gilpin 1991, 1997; McCullough 1996; Hanski 1999).
    We believe habitat loss has reduced the sizes and connectivity 
between patches of suitable and occupied salamander habitat on the 
Santa Rosa Plain. The reduction in the extent and amount of suitable 
water bodies, grasslands, and other suitable upland habitats likely has 
eliminated connectivity among most of the known breeding sites, making 
recolonization of some sites more difficult following local extinction. 
In addition, the reduction of habitat below a certain size threshold 
has the effect of reducing the quality of the remaining habitat by 
reducing the size of habitat boundaries, and making effects of other 
factors such as amount of food, availability of rodent burrows, 
pesticide use, mortality from vehicles, and predators more pronounced 
given the smaller area now exposed to such impacts. We do not have 
enough data to determine what the size threshold for habitat might be, 
whereby any further reduction would lower the quality of the remaining 
habitat. The acreage is probably dependent on factors such as the type 
of building occurring along habitat boundaries (i.e., residential, 
industrial, community park), number of roads bordering the habitat and 
the amount of traffic those roads experience, amount of pesticide use 
within the breeding pool watershed, or whether domestic animals or 
people have access to the site during periods when salamanders are 
vulnerable, such as migrating to or from estivation sites. We believe 
there is a size threshold for habitat below which the combination of 
various impacts will result in the loss of more salamanders than the 
Sonoma County California tiger salamander population can produce, and 
thus local extinction will occur.

Distinct Vertebrate Population Segment

    Under the Act, we must consider for listing any species, 
subspecies, or, for vertebrates, a DPS of these taxa, if there is 
sufficient information to indicate that such action may be warranted. 
To implement the measures prescribed by the Act and its Congressional 
guidance, we, along with the National Marine Fisheries Service, 
developed policy that addresses the recognition of DPSs for potential 
listing actions (61 FR 4722). The policy allows for a more refined 
application of the Act that better reflects the biological needs of the 
taxon being considered, and avoids the inclusion of entities that do 
not require its protective measures. Under our DPS policy, we use two 
elements to assess whether a population segment under consideration for 
listing may be recognized as a DPS. The elements are: (1) The 
population segment's discreteness from the remainder of the species to 
which it belongs; and (2) the significance of the population segment to 
the species to which it belongs. If we determine that a population 
segment being considered for listing represents a DPS, then the level 
of threat to that population segment is evaluated based on the five 
listing factors established by the Act to determine if listing it as 
either threatened or endangered is warranted.


    A population segment of a vertebrate species may be considered 
discrete if it satisfies either one of the following two conditions: 
(1) It is markedly separated from other populations of the same taxon 
as a consequence of physical, physiological, ecological, or behavioral 
factors (Quantitative measures of genetic or morphological 
discontinuity may provide evidence of this separation.); or (2) it is 
delimited by international governmental boundaries within which 
significant differences in control of exploitation, management of 
habitat, conservation status, or regulatory mechanisms exist.
    The Sonoma County California tiger salamander is discrete in 
relation to the remainder of the species. The population is 
geographically isolated and separate from other California tiger 
salamanders. The Sonoma County population is widely separated 
geographically from the closest populations, which are located in 
Contra Costa, Yolo, and Solano counties. These populations are 
separated from the Sonoma County population by the Coast Range, Napa 
River, and the Carquinez Straits, at a minimum distance of about 72 km 
(45 mi). There are no known records of the California tiger salamander 
in the intervening areas (D. Warenycia, CDFG, pers. comm., 2002). We 
have no evidence of natural interchange of individuals between the 
Sonoma County population and other California tiger salamander 
populations. As detailed below, this finding is supported by an 
evaluation of the genetic variability of the species.
    Dr. H. Bradley Shaffer has analyzed the population genetics of the 
California tiger salamander (Shaffer et al. 1993; Shaffer and Trenham 
2002). The most recently available and most comprehensive mitochondrial 
DNA (mtDNA) sequence data indicate that there are six populations of 
California tiger salamander; these six populations are distinguished 
from one another by their mtDNA characteristics (Shaffer and Trenham 
2002). Shaffer et al. 1993 reported that the sequence divergence (a 
percentage indicating the difference among DNA sequences studied) 
between the Sonoma County population was found to diverge on the order 
of 2 percent from other populations of this species. This high level of 
genetic divergence indicates that there has been little, if any, gene 
flow for a significant period of time between the Sonoma County 
population and other California tiger salamander populations. These 
results are supported by additional sampling and mtDNA work of Shaffer 
and Trenham (2002). The ``first, deepest and most significant 
phylogenetic split within California tiger salamander samples is 
between Sonoma County and all others'' (H.B. Shaffer, University of

[[Page 13501]]

California, Davis, in litt, 2002). This is illustrated by the 
phylogenetic tree based on mtDNA in which Sonoma County California 
tiger salamander is the first branch after the outgroup (groups known 
from independent evidence to have branched off earlier than the groups 
under study; Avise 1994, Weir 1996) (Shaffer and Trenham 2002). This 
branch is strongly supported statistically (with bootstrap probability 
of 100 percent) on a phylogenetic tree constructed by the neighbor 
joining method (a method used to construct phylogenetic trees; NJ, 
Avise 1994, Weir 1996). Bootstrapping is a method of statistically 
testing the significance of particular patterns; it involves resampling 
(with replacement) from the existing data sets and then reassessing the 
frequency with which particular groups appear in trees generated from 
the resampled data (Avise 1994, Weir 1996). For the Sonoma County 
California tiger salamander branch a bootstrap probability of 100 
percent means that 100 percent of the trees generated from the 
resampled data had the same configuration. A bootstrap probability of 
seventy percent is the normal criterion for statistical significance in 
the systematic literature (Hillis and Bull 1993 as cited in Shaffer and 
McKnight 1996). In addition to being strongly supported using the NJ 
method, the branch pattern indicating that the Sonoma County population 
is distinct is supported by maximum likelihood and parsimony (Shaffer 
and Trenham 2002), two other methods of constructing phylogenetic trees 
(Avise 1994, Weir 1996). In addition, Shaffer and Trenham (2002) report 
preliminary results of analyses of two nuclear genes. These preliminary 
results also show that Sonoma County California tiger salamanders are 
genetically distinct from other California tiger salamanders. Shaffer 
et al. (1993) suggest that the differences are so large that the Sonoma 
County population may warrant separate taxonomic recognition (Shaffer 
et al. 1993).
    In the proposed rule we relied on the 2 percent divergence value as 
evidence that the Sonoma County California tiger salamander population 
is discrete. At the time, we were using the best available information 
(Shaffer et al. 1993). We note that systematists typically identify 
species boundaries by using phylogenetic analysis rather than absolute 
levels of sequence divergence (Avise 1994, Weir 1996, Hedrick 2000). As 
noted above, the phylogenetic tree (which indicates relationships among 
populations or groups) constructed from the more comprehensive mtDNA 
data of Shaffer and Trenham (2002) indicates that Sonoma County 
California tiger salamanders are very distinct relative to other 
California tiger salamanders, and separated from them on a branch that 
is strongly supported statistically. Therefore, the most comprehensive 
available genetic data (Shaffer and Trenham 2002) for California tiger 
salamanders strongly indicate that Sonoma County California tiger 
salamanders are distinct from other populations of the species.


    Under our DPS policy, once we have determined that a population 
segment is discrete, we consider its biological and ecological 
significance to the larger taxon to which it belongs. This 
consideration may include, but is not limited to, evidence of the 
persistence of the discrete population segment in an ecological setting 
that is unique for the taxon; evidence that loss of the population 
segment would result in a significant gap in the range of the taxon; 
evidence that the population segment represents the only surviving 
natural occurrence of a taxon that may be more abundant elsewhere as an 
introduced population outside its historic range; and evidence that the 
discrete population segment differs markedly from other populations of 
the species in its genetic characteristics. We have found substantial 
evidence that two of these significance factors are met by the 
population of the California tiger salamander that occurs on the Santa 
Rosa Plain in Sonoma County.
    The extinction of the Sonoma County population would result in the 
loss of a significant genetic entity and the curtailment of the range 
of the species. As discussed above, the Sonoma County population is 
genetically distinct from other populations of California tiger 
salamanders. Loss of the Sonoma County population would also eliminate 
the most northern coastal extent of the range of the species. The 
Sonoma County population is geographically isolated. Genetic analysis 
of the species supports the hypothesis that no natural interchange of 
the Sonoma County population occurs with other California tiger 
salamander populations.


    We evaluated the Sonoma County population, addressing the two 
elements which our policy requires us to consider in deciding whether a 
vertebrate population may be recognized as a DPS and considered for 
listing under the Act. We conclude that the Sonoma County population is 
discrete, as per our policy, based on its geographic separation and 
genetic divergence from the rest of the California tiger salamander 
populations. We conclude that the Sonoma County population of the 
California tiger salamander is significant because the loss of the 
species from the Santa Rosa Plain in Sonoma County would result in a 
significant reduction in the species' range and would constitute loss 
of a genetically divergent portion of the species. Because the 
population segment meets both the discreteness and significance 
criteria of our DPS policy, the Sonoma County population of the 
California tiger salamander constitutes a DPS which qualifies for 
consideration for listing. An evaluation of the level of threat to the 
DPS based on the five listing factors established by the Act follows.

Previous Federal Action

    On September 18, 1985, we published the Vertebrate Notice of Review 
(NOR) (50 FR 37958), which included the California tiger salamander as 
a category 2 candidate species for possible future listing as 
threatened or endangered. Category 2 candidates were those taxa for 
which information contained in our files indicated that listing may be 
appropriate but for which additional data were needed to support a 
listing proposal. The January 6, 1989, and November 21, 1991, NORs (54 
FR 554 and 56 FR 58804, respectively) also included the California 
tiger salamander as a category 2 candidate, soliciting information on 
the status of the species.
    On February 21, 1992, we received a petition from Dr. H. Bradley 
Shaffer of the University of California, Davis (UCD), to list the 
California tiger salamander as an endangered species. We published a 
90-day petition finding on November 19, 1992 (57 FR 54545), concluding 
that the petition presented substantial information indicating that 
listing may be warranted. On April 18, 1994, we published a 12-month 
petition finding (59 FR 18353) that the listing of the California tiger 
salamander was warranted but precluded by higher priority listing 
actions. We elevated the species to category 1 status at that time, 
which was reflected in the November 15, 1994, NOR (59 FR 58982). 
Category 1 candidates were those taxa for which we had on file 
sufficient information on biological vulnerability and threats to 
support preparation of listing proposals.
    We discontinued the use of different categories of candidates in 
the February 28, 1996, NOR (61 FR 7596), and defined ``candidate 
species'' as those meeting the definition of former category 1. We 
maintained the California tiger salamander as a candidate species in 
that NOR, as well

[[Page 13502]]

as subsequent NORs published September 19, 1997 (62 FR 49398), October 
25, 1999 (64 FR 57533), and October 30, 2001 (66 FR 54808).
    On June 12, 2001, we received a petition dated June 11, 2001, from 
the Center for Biological Diversity (CBD) and Citizens for a 
Sustainable Cotati to emergency list the Sonoma County population of 
the California tiger salamander as an endangered species and to 
designate critical habitat. On February 27, 2002, CBD filed a complaint 
for our failure to emergency list the Sonoma County population of the 
California tiger salamander as endangered (Center for Biological 
Diversity v. U.S. Fish and Wildlife Service (N.D.Cal.) (Case No. C-02-
0558 WHA)). On June 6, 2002, based on a settlement agreement with the 
CBD, the court signed an order requiring us to submit for publication 
in the Federal Register, a proposed and/or emergency rule to list the 
species by July 15, 2002.
    On July 22, 2002, we published in the Federal Register an emergency 
rule listing the Sonoma County distinct population segment (DPS) of the 
California tiger salamander (Sonoma County California tiger salamander) 
on an emergency basis because we found that a number of threats 
constituted immediate and significant risk to the species (67 FR 
47726). We concurrently published a proposed rule to list this taxon as 
endangered (67 FR 47758). The proposed rule opened a 60-day comment 
period which closed on September 20, 2002. On August 26, 2002, we 
published a notice in the Federal Register notifying the public of a 
hearing to be held on October 1, 2002, and extending the comment period 
until October 21, 2002 (67 FR 54761). On October 31, 2002, we re-opened 
the comment period for 45 days (67 FR 66377). The re-opened public 
comment period closed on December 16, 2002. This final rule to 
designate the Sonoma County California tiger salamander as an 
endangered species complies with the June 6, 2002, settlement 
    As required by section 4(b)(1) of the Act, our decision to list the 
Sonoma County population of the California tiger salamander is based 
upon the best available information at this time. We note that the 
petition and subsequent emergency listing of this population has led to 
increased interest in this population by a variety of parties, and thus 
to an acceleration of the rate at which new information is becoming 
available. We expect this trend to continue subsequent to this final 
listing determination. The settlement agreement discussed above 
requires that we submit to the Federal Register a proposed rule to list 
the California tiger salamander range wide by May 15, 2003, and make a 
final listing determination on that proposal by May 15, 2004. As a part 
of that rulemaking we intend to review all then-current information 
regarding both the Sonoma County and Santa Barbara County populations, 
including whether they constitute valid distinct population segments, 
and render a final determination on the California tiger salamander 

Summary of Comments and Recommendations

    In the July 22, 2002, proposed rule (67 FR 47758), we requested all 
interested parties submit factual reports, information, and comments 
that might contribute to development of a final determination. We 
contacted appropriate Federal agencies, State agencies, county and city 
governments, scientific organizations, affected landowners and other 
interested parties requesting comments. We published legal notices in 
the Santa Rosa Press Democrat on July 29, 2002, and September 3, 2002, 
and the Sonoma Index-Tribune on July 30, 2002, and September 27, 2002, 
notifying the public of the comment period on the proposed and 
emergency rule and the public hearing, respectively. We requested 12 
peer reviewers to comment on the proposed rule in compliance with our 
policy, published in the Federal Register on July 1, 1994 (59 FR 
    During both public comment periods, we received 111 comment letters 
from public agencies, individuals, businesses, and organizations, with 
several commenters submitting more than one set of comments during the 
subsequent extensions of the comment period. We received oral comments 
from 49 people at the public hearing. Ninety-nine commenters opposed 
the listing, 60 supported the listing, and one was neutral. The 
breakdown of the comments included none from Federal agencies, 2 from 
State agencies, 8 from Sonoma County and city agencies, 49 from 
organizations or corporations, and 99 from individuals. One hundred and 
twenty people attended the hearing, with 31 individuals and 18 
representatives of organizations providing oral comments. In total, 39 
commenters at the hearing were opposed to the listing, 9 supported the 
listing, and 1 was neutral. Several comments were received after the 
comment period closed.
    We updated the final rule to reflect comments and information we 
received during the comment periods. We address substantive comments 
concerning the rule below. Comments of a similar nature are grouped 
together (referred to as ``Issues'' for the purpose of this summary).
    Issue 1: Some commenters questioned the validity of our DPS 
determination for Sonoma County California tiger salamander, suggesting 
that the genetic data do not support a DPS. One commenter specifically 
suggested that the evidence that Sonoma County California tiger 
salamander is a separate species or subspecies and use of this as a 
criterion for a DPS is less clear than we indicated in our emergency 
rule. The commenter also suggests that there is little evidence that 
California tiger salamander populations in different parts of 
California represent separate species or subspecies. The commenter also 
noted that, while the unpublished Shaffer et al. (1993) suggest Sonoma 
County may warrant species status, Shaffer and McKnight (1996) make no 
such claim in their published paper.
    Response: Genetic distinctness or the presence of genetically 
determined traits may be important in recognizing some DPS's, but this 
kind of evidence is not specifically required in order for a DPS to be 
recognized. Genetic information can play two different roles in the 
evaluation of whether a population should be recognized as a distinct 
vertebrate population segment for the purposes of listing under the 
Act. First, quantitative genetic information may, but is not required 
in order to provide evidence that the population is markedly separated 
from other populations and thus meets the DPS policy's criterion of 
being discrete. The DPS policy's standard for discreteness is meant to 
allow an entity given DPS status under the Act to be adequately defined 
and described. The standard adopted is believed to allow entities 
recognized under the Act to be identified without requiring an 
unreasonably rigid test for distinctness. At the same time, the 
standard does not require absolute separation of a DPS from other 
members of its species, because this can rarely be demonstrated in 
nature for any population of organisms. Second, genetic characteristics 
that differ markedly from other populations may be one consideration in 
evaluating the discrete population segments biological and ecological 
significance to the taxon to which it belongs.
    Restricting listings to full taxonomic species would render the 
Act's definition of species, which explicitly includes subspecies and 
DPS's of vertebrates, superfluous.

[[Page 13503]]

    We did note in our emergency rule that Dr. Shaffer and his 
colleagues believe the divergence of Sonoma County California tiger 
salamanders justifies separate species recognition (Shaffer et al. 
1993). Our DPS policy (61 FR 4722), however, does not require that 
levels of differentiation warranting taxonomic revision be identified 
for the DPS criteria to be met. In fact, our DPS policy is used for 
identifying groups within species or subspecies that may warrant 
listing under the ESA. Therefore, our DPS determination for Sonoma 
County California tiger salamander is not based on whether the 
divergence observed warrants separate taxonomic recognition, but rather 
on the relatively high divergence of the Sonoma County population from 
other populations of California tiger salamanders.
    The Sonoma County population of California tiger salamanders is the 
most divergent of any population of the species. This finding is 
supported by the original mitochondrial DNA (mtDNA) work of Shaffer et 
al. (1993) and by additional sampling and mtDNA work of Shaffer and 
Trenham (2002). The ``first, deepest and most significant phylogenetic 
split within California tiger salamander samples is between Sonoma 
County and all others'' (H.B. Shaffer, in litt., 2002). This is 
illustrated by the phylogenetic tree based on mtDNA in which Sonoma 
County California tiger salamander is the first branch after the 
outgroup (Shaffer and Trenham 2002). This branch is strongly supported 
statistically (with bootstrap probability of 100 percent) on a 
phylogenetic tree constructed by the neighbor joining (NJ) method. 
Seventy percent is the normal criterion for statistical significance of 
bootstrap proportions in the systematic literature (Hillis and Bull 
1993 as cited in Shaffer and McKnight 1996). In addition, the branch 
pattern indicating that the Sonoma County population is distinct is 
supported by maximum likelihood and parsimony (Shaffer and Trenham 
2002), two other methods of constructing phylogenetic trees (Avise 
1994, Weir 1996). In addition, Shaffer and Trenham (2002) report 
preliminary results of analyses of two nuclear genes. These preliminary 
results also show that Sonoma County California tiger salamanders are 
genetically distinct from other California tiger salamanders. 
Therefore, we believe that the levels of divergence observed in Sonoma 
County California tiger salamanders provide substantial evidence of the 
significance of the population.
    Shaffer and McKnight (1996) do not mention whether the divergence 
of Sonoma County California tiger salamanders justifies separate 
species recognition. They make no statements about the taxonomic status 
of Sonoma County California tiger salamanders in their paper. In the 
Discreteness section of the emergency rule, we incorrectly attributed 
the statement that Sonoma County California tiger salamanders warrant 
separate taxonomic recognition to the 1996 publication. In fact, no 
Sonoma County California tiger salamanders were sampled in the study 
(Appendix 1 of Shaffer and McKnight 1996). The paper examined 
evolutionary relationships among tiger salamander species and 
subspecies and did not include a formal taxonomic treatment of the 
tiger salamander complex. Therefore, it is not surprising that the 
authors did not specifically note whether or not the divergence of 
Sonoma County California tiger salamanders justifies species status.
    Issue 2: One commenter also implied that the discreteness criterion 
of our DPS policy was only met by genetic data.
    Response: Two professional biologists who commented reported that 
the Sonoma County population is geographically isolated from other 
populations of the California tiger salamander. We note that the 
proposed rule discussed the geographic separation of the Sonoma County 
population from other populations of California tiger salamander. The 
Sonoma County population is separated from other California tiger 
salamander populations by the Coast Range, Napa River, and the 
Carquinez Straits, a distance of about 72 km (45 mi).
    Issue 3: Some commenters felt that 2 percent divergence of the 
Sonoma population of the California tiger salamander from the remainder 
of the California tiger salamander population is not meaningful or 
worthy of recognition as a DPS.
    Response: We note that species boundaries are typically identified 
by systematists using phylogenetic analysis rather than absolute levels 
of sequence divergence. The intraspecific sequence divergence value of 
2 percent depends on the total number of nucleotides sequenced for each 
gene region. This can differ significantly from species to species or 
from study to study and is therefore a relative value (Avise 1994, Weir 
1996, Hedrick 2000). Comparisons need to be made from the same 
baseline. From a DPS perspective, percent sequence divergence is less 
important than the phylogenetic relationships depicted with strong 
statistical support in the neighbor joining (NJ) tree that indicate the 
distinctive genetic character of Sonoma County California tiger 
salamanders. The phylogenetic tree (which indicates relationships among 
populations or groups) constructed from the mtDNA data of Shaffer and 
Trenham (2002) indicates that Sonoma County California tiger 
salamanders are very distinct relative to other California tiger 
salamanders, and separated from them on a branch that is strongly 
supported statistically. Therefore, the most comprehensive available 
genetic data (Shaffer and Trenham 2002) for California tiger 
salamanders strongly indicate that Sonoma County California tiger 
salamanders are distinct from other populations of the species.
    Issue 4: One commenter analyzed Shaffer and McKnight's (1996) 
divergence values for various Ambystoma tigrinum subspecies and for 
California tiger salamander, finding that divergence between 
populations in different groups (e.g., between California tiger 
salamander and A. tigrinum subspecies and other such combinations among 
species and subspecies versus within a species or subspecies) had a 
mean of 6.37 percent and a range of 5.08 percent to 7.41 percent. The 
commenter states that these statistics show the 2 percent divergence of 
the Sonoma County California tiger salamander population is 
    Response: As noted above, one way to meet the significance 
criterion of our DPS policy (61 FR 4722) is for a population to 
``differ markedly from other populations of the species in its genetic 
characteristics'' (emphasis added). We note again that our DPS policy 
focuses on differentiation within species (i.e., the population 
``differs markedly from other populations of the species''). The 
commenter's analysis is of differences among taxonomic groups of tiger 
salamanders, not of within-species or subspecies differences, which are 
the focus of the DPS policy.
    As explained above, we believe the available mtDNA data (Shaffer et 
al. 1993, Shaffer and Trenham 2002) show that the Sonoma County 
population of California tiger salamander is markedly genetically 
divergent from other populations of the California tiger salamander. 
That the sequence divergence value is 2 percent is less important than 
the configuration of the phylogenetic tree, which strongly supports the 
distinctness of Sonoma County California tiger salamanders.
    Issue 5: One commenter stated that one would expect broadly similar 
conclusions from allozyme and mtDNA studies and that for Sonoma County 
California tiger salamanders this was not the case. The commenter noted 

[[Page 13504]]

Shaffer et al.'s (1993) allozyme work did not reveal much variation 
(only 9 of 26 loci were variable) and indicate that Sonoma County 
California tiger salamanders are not distinct from other western 
populations of California tiger salamander from Yolo County to San Luis 
Obispo County.
    Response: A variety of genetic tools are available to assess 
genetic variation. These tools are often referred to as ``genetic 
markers.'' All are indicators of genetic variation, but none is 
considered determinative. Which genetic marker is most useful depends 
on the question being asked and the organism being studied (Haig 1998, 
Parker et al. 1998).
    Allozymes are proteins which are used as genetic markers because 
DNA contains information that is used by cells to build protein. 
Allozymes have been used to assess genetic variation for many years. 
Allozyme studies have the advantage of being relatively inexpensive and 
straightforward, once the basic technique is developed for a group. 
However, drawbacks of using allozymes include the limited number of 
proteins that can be screened (Parker et al. 1998) and the fact that 
they often detect little variability (Haig 1998). On average across 
taxa, less than half of all loci are variable. It is not uncommon for 
population biologists to encounter species for which allozymes cannot 
be used as genetic markers because they lack variation (Parker et al. 
    Molecular techniques, such as mtDNA, allow biologists to examine 
variation in DNA directly, rather than looking at the product derived 
from DNA (i.e., proteins) (Parker et al. 1998). Analysis of animal 
mtDNA is the most commonly used technique for examining phylogenetic 
relationships among populations of the same species and among closely 
related species (Taberlet 1996). One advantage of mtDNA in particular 
is its high rate of evolution (i.e., rate of nucleotide substitution) 
compared to other DNA (Taberlet 1996, Parker et al. 1998). The D-loop 
(which Shaffer and colleagues examined for their tiger salamander 
studies) is especially variable, making it useful to study recently 
divergent populations or species. Different genetic techniques are 
expected to resolve different amounts of variation because the genetic 
markers used have different evolutionary characteristics (Parker et al. 
1998). The observation that some characters (in this case, allozymes) 
are not variable does not diminish the utility of other data (in this 
case mtDNA) in describing relationships among groups.
    Issue 6: Several commenters felt that our finding that California 
tiger salamanders in Sonoma County qualified as a DPS was based on an 
isolated, and dated, report (i.e., Shaffer et al. (1993). One commenter 
noted several times that Shaffer et al. (1993), the source of mtDNA 
data for California tiger salamanders, is an unpublished report.
    Response: We are required to use the best available scientific 
data. In this case, the data were in an unpublished report. During the 
comment period, we received a second report (Shaffer and Trenham 2002) 
that contained findings similar to Shaffer et al. 1993 but which was 
based on more extensive data collection. The publication of Shaffer and 
McKnight (1996) using mtDNA techniques for California and other tiger 
salamanders and the publication of mtDNA work by Shaffer et al. (2000) 
on Yosemite toad (Bufo canorus) gives us confidence that Shaffer's work 
is scientifically defensible.
    Issue 7: Several commenters noted that recent aerial photos and a 
map that is based on the photos show 515 or more pools located within, 
or in the vicinity of, the Santa Rosa Plain. They believe these could 
potentially provide habitat for the Sonoma County California tiger 
salamander. They stated that many of the pools have not been surveyed 
and, therefore, the species could be more widespread in Sonoma County 
than is currently known.
    Our Response: The map submitted displayed 515 water bodies and was 
based on interpretation of aerial photography with little on-the-ground 
verification. We compared the map of potential habitat for the 
California tiger salamander to information and data we obtained and 
have determined 360 water bodies can be eliminated as potential habitat 
for the California tiger salamander due to a variety of factors 
including: unsuitable soils, unsuitable vegetation, high elevation, 
presence of aquatic predators, agricultural development (row crops, 
vineyards, etc.), urbanization, and unsuitable hydrology. One hundred 
and fifty-five water bodies remained within the suitable habitat area.
    Of the 155 remaining water bodies, 53 were characterized as ``man-
made long'' and ``natural long'' ponds/wetlands, which hold water for 
too long and /or harbor aquatic predators, and were eliminated as 
potential habitat for the California tiger salamander. Another set of 
water bodies were ``man-made short'' and ``natural short'' ponds/
wetland (12 in total) which do not hold water long enough to be a 
source of potential habitat for the California tiger salamander. 
Consequently only ``man-made moderate'' and ``natural moderate'' mapped 
water bodies were considered potential suitable habitat (90 in total).
    Of the ``man-made moderate'' and ``natural moderate'' mapped water 
bodies, four were formerly known breeding sites that have been 
eliminated and eight are currently identified as existing breeding 
sites. Some of the mapped water bodies are anticipated to have aquatic 
predators given their location on the Laguna de Santa Rosa floodplain, 
which would limit California tiger salamander utilization. Others 
contain habitat with sightings near the ponds, but these ponds have 
been repeatedly surveyed by experts, with results indicating they do 
not support breeding populations of California tiger salamanders.
    The determination that some of the mapped water bodies contain 
potential habitat is solely based on aerial photographs; however, the 
majority of these are on private property and inaccessible to surveying 
without landowner permission. Several recognized salamander biologists 
have conducted repeated road surveys in Sonoma County along areas where 
the California tiger salamander is known to exist or where suitable 
habitat appears to exist (D. Cook, The Wildlife Society, pers. comm., 
2002; P. Northen, California State University, Sonoma, pers. comm., 
2002; J. Seifers, Santa Rosa, California, per. comm., 2002; H. B. 
Shaffer, pers. comm., 2002; P. C. Trenham, UCD, pers. comm., 2002). 
Night driving is a standard technique for surveying for reptiles and 
amphibians (Shaffer and Juterbock 1994; Parris 1999). The locations 
where these biologists found breeding sites, migrating adult 
salamanders, subadults, larvae, and egg masses in roadside ditches were 
entered into the CNDDB. This data is considered essential (D. McGriff, 
CDFG, pers. comm., 2002) and the data was utilized in our analysis of 
the status of the California tiger salamander in Sonoma County. Several 
of the experts indicated that there are likely to be a few small 
breeding sites or potential habitat for California tiger salamanders on 
private lands containing grassland areas and suitable soils on the 
Santa Rosa Plain, including stock ponds (P. Northen, pers. comm., 2002; 
H. B. Shaffer, pers. comm., 2002; P. C. Trenham, pers. comm., 2002); 
however, these private lands were inaccessible during their survey 
    Issue 8: One commenter believed that two sites not specifically 
mentioned in the proposed rule should be included as breeding sites for 
California tiger salamanders.

[[Page 13505]]

    Our Response: We evaluated the two sites mentioned by the 
commenter. They are the Hartunian (Scenic Avenue) Preserve and the 
Southwestern Santa Rosa Vernal Pool Preservation Bank (Engel Bank).
    The Hartunian Preserve is approximately 14 hectares (ha) (34 acres 
(ac)) in size and has one shallow swale that could support successful 
breeding during a rainy season of above-average rainfall. This preserve 
was not listed in the emergency rule and has not been included in the 
final rule because breeding by the species is not likely to occur 
during years of low to average rainfall.
    Upon review of all information available, we have concluded that 
the Engel Bank does meet the biological requirements for California 
tiger salamander breeding and we have included this site as an eighth 
breeding site. Engel Bank is a 16-ha (40-ac) preserve that contains 
approximately 7-ha (18-ac) of wetlands and has documented records of 
the species. However, California tiger salamanders require a fairly 
large upland component. Approximately 9 ha (22 ac) of protected uplands 
are available at this site. Therefore, due to the limited upland 
habitat protected within the Engel Bank, a sustainable population at 
this site is dependent on the activities occurring on the surrounding 
private property.
    Issue 9: Many commenters stated that the California tiger 
salamander is adequately protected by current regulations. Examples of 
current regulations cited include the application of the Porter-Cologne 
Water Quality Control Act and the California Environmental Quality Act 
(CEQA) by CDFG. Both of these require one-to-one mitigation for 
projects impacting the species. Commenters also mentioned strict local 
land use controls enacted by Sonoma County and cities within the Santa 
Rosa Plain. In addition, commenters noted that the Sonoma County 
Agricultural and Open Space District has acquired potential California 
tiger salamander habitat that is set aside as open space through a 
county-wide sales tax. They felt these preserves are adequate for the 
animal. Several other commenters stated that current legal protections 
have been inadequate for the species, and losses of breeding sites have 
    Our Response: CDFG lists the California tiger salamander as a 
species of special concern and has no specific regulatory mechanism to 
require mitigation for impacts to this species. In some instances, the 
CDFG has obtained one-to-one mitigation for destruction of California 
tiger salamander breeding sites. However, five breeding sites have been 
eliminated in Sonoma County during the past 2 years without new 
breeding sites being created. The use of CEQA and the Porter-Cologne 
Water Quality Control Act have not halted the loss of habitat for this 
species in Sonoma County. The land use controls enacted by the County 
and cities have not required adequate compensation for the loss of 
breeding sites. The Sonoma County Agricultural and Open Space District 
has acquired acreage through a one-quarter of a cent county sales tax. 
However, the acreage purchased does not overlap with areas known to 
contain California tiger salamander breeding sites. A majority of their 
purchased lands lie outside of the Santa Rosa Plain. Of the lands they 
have purchased within the Santa Rosa Plain, the majority fall within 
the floodplain of the Laguna de Santa Rosa River. There are no known 
records of the California tiger salamander within this 100 year 
    Issue 10: Many commenters stated that the comment period did not 
allow sufficient time for meaningful public input. A number of them 
said that more time was needed to complete surveys that currently are 
    Our Response: The comment period for the proposed rule was 
initially open for 60 days, closing on September 20, 2002. On August 
26, 2002, the comment period was extended until October 21, 2002. The 
comment period was re-opened on October 31, 2002, for an additional 45 
days. In total, the comment period was open for 145 days.
    At least 12 surveys are ongoing in Sonoma County in three areas not 
previously known to have California tiger salamander occurrences, and 
to date, there have been no detections of the animal. We agree that 
additional survey information is valuable. However, the Service has not 
had the flexibility to wait until surveys are finished because an 
order, issued by the district court in Center for Biological Diversity 
v. U.S. Fish and Wildlife Service, required us to complete this rule 
before the expiration of the protection afforded the DPS by the 
emergency rule.
    Issue 11: One commenter stated that we should extend the comment 
period because we had not made available to the public documents on 
which the emergency listing and permanent listing was based.
    Our Response: As stated in the emergency rule, the complete file 
for the rule is available for inspection, by appointment, during normal 
business hours at the Sacramento Fish and Wildlife Office. In addition, 
the proposed rule stated that all comments received during the comment 
period were available for public review. The complete file for this 
rule is available for inspection, by appointment, during normal 
business hours at the Sacramento Fish and Wildlife Office.
    Issue 12: Several commenters felt we should complete peer review 
and incorporate that analysis into a proposed rule.
    Our Response: In accordance with our July 1, 1994, Interagency 
Cooperative Policy for Peer Review in Endangered Species Act Activities 
(59 FR 34270), we solicited review from 12 experts in the fields of 
ecology, conservation, genetics, taxonomy and management. The purpose 
of such a review is to ensure that listing decisions are based on 
scientifically sound data, assumptions, and analyses, including input 
from appropriate experts. The five peer reviewers who sent comments 
supported listing of the Sonoma County California tiger salamander. 
They provided additional documentation on the distribution, genetics, 
and threats to the species. This information has been incorporated into 
this final rule.
    Issue 13: Numerous commenters felt the proposal to list the Sonoma 
County California tiger salamander was based on one study conducted by 
a group with a very specific agenda against property rights and 
development. They said listing decisions should be based on specific 
studies by non-partisan professionals. Two commenters felt that the 
proposed rule was based on inaccurate or incomplete data. Numerous 
commenters felt the data we utilized on the California tiger salamander 
was at least 10 years old and was thus not current or accurate. One 
recognized herpetologist provided additional peer-reviewed articles on 
the California tiger salamander from scientific journals. Another 
professional biologist noted the proposed rule was based on research 
conducted as recently as 2001 by knowledgeable herpetologists.
    Our Response: We used the best scientific and commercial 
information available during the status review process and preparation 
of the emergency and final rules to make our listing determination. We 
utilized museum records; CNDDB information; aerial photographs 
documenting the land use changes over the last 60 years; reports 
produced by the Sonoma County Agricultural Commissioners and the Sonoma 
County Planning and Development Department; unpublished reports by 
biologists; and peer-reviewed articles from scientific journals in 
making that determination.

[[Page 13506]]

    Out of 126 citations appearing in the emergency rule, 52 have been 
published within the past 5 years (41 percent) and 83 citations have 
been published within the past 10 years (66 percent). The initial 
report on the population genetics of the California tiger salamander by 
Shaffer et al. (1993) has been substantiated by additional research 
(Barry and Shaffer 1994; Fisher and Shaffer 1996; Shaffer and McKnight 
1996; Cook and Northen 2001; Shaffer and Trenham 2002).
    Issue 14: Some commenters felt we had not quantified the magnitude 
of loss of the California tiger salamander in Sonoma County. One 
herpetologist said we had presented accurate information on the status 
of the species in Sonoma County.
    Our Response: Based on the best available scientific and commercial 
information, five breeding sites for the California tiger salamander in 
Sonoma County have been destroyed in the past 2 years, and there are 
only eight known breeding sites remaining. Five of these sites are on 
private lands with no effective regulatory protection. Only one of the 
three protected sites is over 32 ha (80 ac) in size. All known breeding 
sites in the Cotati area have now been destroyed. The remaining sites 
in the Cotati area where the animals can mate and develop are roadside 
ditches and other suboptimal habitat during years of above average 
    Issue 15: According to some commenters, there has been no study to 
determine population trends or ways to improve breeding at the known 
preserves containing the California tiger salamander.
    Our Response: All of the three protected sites known to contain 
salamanders have been surveyed for the past 4 years. All surveys at 
these sites have resulted in the detection of very low numbers of 
salamander larvae during years that they were found at all. The largest 
preserve is approximately 81 ha (200 ac) in size, yet continues to 
exhibit very low numbers of larvae as indicated by yearly surveys. It 
is probable that salamander populations are limited by the lack of 
uplands for estivation during the dry season.
    Issue 16: A number of commenters asked us to delay a final listing 
decision until a full review of the scientific evidence supporting or 
disputing the status of the Sonoma County California tiger salamander 
had been presented in a public forum.
    Our Response: The purpose of publishing a proposed rule and 
soliciting public input during the comment period is to fully involve 
the public in the listing process. We also held a workshop and public 
hearing in Santa Rosa, California, to encourage agency and public input 
into the review of the proposed rule. We solicited 12 recognized 
experts and specialists to review the proposed rule. We utilized this 
information in making the final determination.
    Issue 17: Numerous commenters said the listing of the California 
tiger salamander would have a severe economic impact on Sonoma County. 
They said we should complete an analysis of the economic effects of 
listing and include it in the final rule.
    Our Response: Under section 4(b)(1)(A) of the Endangered Species 
Act of 1973, as amended (Act) (16 U.S.C. 1531 et seq.), we must base a 
listing decision solely on the best scientific and commercial data 
available. The legislative history of this provision clearly states the 
intent of Congress to ensure that listing decisions are ``* * * based 
solely on biological criteria and to prevent non-biological criteria 
from affecting such decisions* * * '' (House of Representatives Report 
Number 97-835, 97th Congress, Second Session 19 (1982)). As further 
stated in the legislative history, ``* * * economic considerations have 
no relevance to determinations regarding the status of species * * 
*''(Id. at 20). Therefore, we did not consider the economic impacts of 
listing the Sonoma County California tiger salamander.
    Issue 18: Two commenters stated that critical habitat has not been 
proposed and, therefore, the listing is in violation of the Act.
    Our Response: Pursuant to section 4(a)(3) of the Act, we have 
determined that designation of critical habitat is prudent for the 
Sonoma County California tiger salamander (see the ``Critical Habitat'' 
section). However, our budget for listing activities is currently 
insufficient to allow us to immediately complete all the listing 
actions required by the Act. Listing the DPS without designating 
critical habitat at this time allows us to provide protections needed 
for the conservation of the species without further delay. This is 
consistent with section 4(b)(6)(C)(i) of the Act, which states that 
final listing decisions may be issued without critical habitat 
designations when it is essential that such determinations be promptly 
published. We will prepare a critical habitat designation in the future 
when our available resources allow.
    Issue 19: One commenter said the 1995 Santa Rosa Plain Vernal Pool 
Ecosystem Preservation Plan indicated the Sonoma County California 
tiger salamander is potentially less vulnerable than stated in our 
proposed rule.
    Our Response: The Santa Rosa Plain has experienced rapid urban 
growth since the vernal pool ecosystem preservation plan was issued in 
1995. From 1995 until 2001, the population of Sonoma County increased 
by approximately 10% with an average annual growth rate of 
approximately 1.6 percent. (U.S. Census Bureau; California Department 
of Finance; California Association of Realtors website 2002). Increases 
in housing, traffic, industry, and office buildings have occurred 
concurrent with the increase in population growth. In the past 2 years, 
five breeding sites for the Sonoma County California tiger salamander 
have been destroyed. Loss of real and potential salamander breeding 
sites and estivation habitat continues to occur in the Santa Rosa 
Plain. Given the amount of habitat loss, inadequate regulatory 
mechanisms, and other threats, we believe the remaining California 
tiger salamanders in Sonoma County are endangered.
    Issue 20: Several commenters stated that we should compensate 
private landowners for the loss of revenue that occurs when California 
tiger salamanders are found on their land. Another commenter said the 
``Cattle Growers'' ruling prohibits us from imposing land use 
restrictions predicated upon listing except through a designation of 
critical habitat, and not doing so constitutes unlawful taking of 
property without compensation.
    Our Response: The presence of an endangered or threatened species 
does not prevent all uses of public or private lands. The listing of a 
species does not impose land use restrictions and, therefore, does not 
result in unlawful taking of property. In addition, we will assist 
landowners in the identification of proposed activities that could 
result in take (harass, harm, pursue, hunt, shoot, wound, kill, trap, 
capture, or collect, or to attempt to engage in any such conduct), 
develop measures to minimize the potential for take, and work with them 
to obtain authorizations for incidental take through sections 7 and 10 
of the Act. Recovery planning for this species may include 
recommendations for land acquisition or easements involving private 
landowners. Any such efforts will be undertaken with the full 
cooperation of the landowners.
    A recent case pertinent to this issue, Arizona Cattle Growers v. 
Fish and Wildlife and Bureau of Land Management (9th Circuit Court of 
Appeals 99-16102), provides that, in

[[Page 13507]]

biological opinions issued pursuant to section 7 of the Act, the terms 
and conditions in a biological opinion must have an articulated, 
rational connection to the take of a listed species. The court stated 
that the Act provides for the designation of critical habitat outside 
the geographic range currently occupied by a listed species when ``such 
areas are essential for the conservation of the species.'' Absent this 
procedure, the court stated that there is no evidence that Congress 
intended to allow the Service to regulate any parcel of land that is 
merely capable of supporting a listed species. Therefore, the mere 
listing of species, such as the Sonoma County California tiger 
salamander, will not result in land use restrictions.
    Issue 21: One commenter was concerned that existing vineyards and 
wineries would be burdened by excessive costs when water permits are 
required or changed, or when planting or replanting permits are 
    Our Response: Once a species becomes listed, section 9 of the Act 
sets forth a series of general prohibitions that apply to that species. 
The Sonoma County California tiger salamander is protected from 
``take'' by any person subject to the jurisdiction of the United 
States. The definition of take under the Act includes harass, harm, 
pursue, hunt, shoot, wound, kill, trap, capture, collect, or attempt to 
engage in any such conduct. Harm is further defined to include 
significant habitat modification or degradation that results in death 
or injury to the listed wildlife by significantly impairing behavioral 
patterns such as breeding, feeding, or sheltering. Harass is further 
defined to include actions that create the likelihood of injury to 
listed wildlife by annoying it to such an extent as to significantly 
disrupt normal behavior patterns which include, but are not limited to, 
breeding, feeding, or sheltering. Therefore, if the action by a party, 
such as water use by a vineyard or winery, planting or replanting of 
vineyards, could result in ``take'' of a listed species, then 
authorization for incidental take should be obtained pursuant to either 
sections 7 or 10 of the Act.
    Issue 22: One commenter felt that the CDFG considered the emergency 
listing inappropriate due to a lack of proper information and 
sufficient scientific support.
    Our Response: Only species or subspecies, and not distinct 
population segments, of vertebrates can be listed as endangered or 
threatened under the California Endangered Species Act (California 
Department of Fish and Game internet web site 2003). However, the 
California Department of Fish and Game has expressed concern for 
adverse impacts to the salamander and its habitat (R. Floerke, CDFG, in 
litt., 2002).
    Issue 23: One commenter stated that the breeding sites identified 
in the emergency rule for the Sonoma County California tiger salamander 
are not threatened, and the sites around the old airfield would not be 
destroyed because construction will avoid them and be limited to the 
runway. The commenter also felt the degree of threat, isolation of 
habitats, and barriers to movement were overstated and not based in 
reality. This same commenter believed that the Roseland Creek channel 
and asphalt run-way already constitute a significant barrier to 
migrating salamanders at the old airfield. Several other commenters 
noted the vernal pools at the Southwest Air Center (Air Center) have 
been damaged, destroyed, or are currently on the verge of being lost.
    Our Response: Other than approximately 28 ha (70 ac) designated as 
open space, the remainder of the Air Center has been designated for 
development in the Southwest Santa Rosa Area Development Plan. One of 
the breeding sites could be destroyed by development and two others 
could be isolated and imperiled by a loss of estivation habitat. Upon 
development of this area, not enough upland will likely remain to 
support a viable salamander population even if two of the three 
breeding sites are not destroyed. Proposed development could also 
isolate the Federal Emergency Management Agency (FEMA)/Broadmore North 
    Burrowing mammals also could be increasingly subject to control 
actions given the proximity of developed areas to any remaining 
estivation habitats. One proposed development project at the Air Center 
could fill two wetlands that make up one of the eight known breeding 
sites. Surveys of this site over the past 2 years have found breeding 
California tiger salamanders. Construction on the runway itself and 
extension of Fresno Avenue could result in total isolation of the FEMA/
Broadmore North Preserves, a known Sonoma County California tiger 
salamander breeding site. We have determined that Roseland Creek 
Channel is not likely to be a barrier to salamander migration. Flows in 
the channel are minimal, except during the heaviest of rain events.
    Issue 24: One commenter felt that the emergency rule overstated the 
effects of development at the Air Center because the runways are too 
hot for salamanders to cross.
    Our Response: Hot runways are not a concern for this species 
because California tiger salamanders are in estivation during the dry, 
hot, summer months. The nocturnal adult animals concentrate their 
movements during rain events in the cooler fall, winter, and spring 
months. Researchers conducting night-time road surveys for California 
tiger salamanders during the fall, winter, and spring have documented 
this species crossing roads on many occasions.
    Issue 25: One commenter stated that California tiger salamanders 
exist in the Central Valley and coastal areas of California and, 
therefore, they could not be endangered.
    Our Response: Research has indicated there are six populations of 
California tiger salamanders occurring in California. These include the 
Santa Rosa area of Sonoma County; the Bay Area (central and southern 
Alameda, Santa Clara western Stanislaus, western Merced, and the 
majority of San Benito counties); Central Valley (Yolo, Sacramento, 
Solano, eastern Contra Costa, northeast Alameda, San Joaquin, 
Stanislaus, Merced, and northwestern Madera counties); southern San 
Joaquin Valley (portions of Madera, central Fresno, and northern Tulare 
and Kings counties); Central Coast Range (southern Santa Cruz, 
Monterey, northern San Luis Obispo, and portions of western San Benito, 
Fresno, and Kern counties); and Santa Barbara County (Shaffer and 
Trenham 2002). The Sonoma County population meets the requirements of 
our Distinct Population Segment policy and therefore can be separated 
from the remainder of the population in making this determination.
    Issue 26: One commenter stated that much of the area defined as 
potential range of the Sonoma County California tiger salamander was 
based on soil types.
    Our Response: The distribution of the Sonoma County California 
tiger salamander corresponds to the distribution of specific soil 
types. The known breeding sites of the animal in Sonoma County are 
restricted to Huichica-Wright-Zamora and Clear Lake-Reyes soils series/
associations as defined by the USDA (1972, 1990). The poorly drained 
soils in the Huichica-Wright-Zamora association are considered prime 
soils for containing wetlands, and more specifically, prime soils for 
habitat containing California tiger salamander (P. Northen, pers. 
comm., 2002). The Huichica-Wright-Zamora association is restricted to 
the Santa Rosa Plain and the vicinity of the town of Sonoma (USDA 1972, 
1990). The poorly drained soils in the Clear

[[Page 13508]]

Lake-Reyes association are considered suitable to marginal soils for 
containing wetlands or habitat for California tiger salamander (P. 
Northen, pers. comm., 2002). The Clear Lake-Reyes association is found 
from the Cotati region south and east of Petaluma to the tidelands of 
northern San Francisco Bay where the salt marsh habitat is unsuitable 
for the California tiger salamander. There are also scattered areas of 
the Clear Lake-Reyes association found south and southwest of the town 
of Sonoma (USDA 1972, 1990). There are no known records of the 
California tiger salamander from the area around the town of Sonoma (D. 
McGriff, pers. comm., 2002), and there is now extensive urban and 
agricultural development in this portion of the county.

Peer Review

    In accordance with our July 1, 1994, Interagency Cooperative Policy 
for Peer Review in Endangered Species Act Activities (59 FR 34270), we 
solicited the expert opinions of 12 independent specialists regarding 
pertinent scientific or commercial data and assumptions relating to the 
taxonomy, population status, and supporting biological and ecological 
information for the California tiger salamander in Sonoma County. The 
purpose of such review is to ensure that listing decisions are based on 
scientifically sound data, assumptions, and analyses, including input 
of appropriate experts and specialists. Information and suggestions 
provided by the reviewers were incorporated or addressed as applicable.
    We received peer reviews from five of the experts. All of them 
agreed the Sonoma County California tiger salamander is imperiled 
throughout all or a portion of its range. One reviewer provided 
references on threats from disease the reviewer believed relevant to 
our final rule decision. This peer reviewer also stated that threats 
from disease are much more severe for small populations. Another peer 
reviewer recommended a number of editorial clarifications in the 
emergency and proposed rules. The third peer reviewer stated that the 
California tiger salamander should be listed throughout its range. A 
fourth peer reviewer provided additional information on the California 
tiger salamander, and the fifth peer reviewer, based on years of field 
work, agreed that the Sonoma County California tiger salamander is 

Summary of Factors Affecting the Species

    Section 4 of the Act and regulations (50 CFR part 424) promulgated 
to implement the listing provisions of the Act describe the procedures 
for adding species to the Federal list. We may determine a species to 
be endangered or threatened due to one or more of the five factors 
described in section 4(a)(1). These factors, and their application to 
the Sonoma County California tiger salamander, are as follows:

A. The Present or Threatened Destruction, Modification, or Curtailment 
of Its Habitat or Range

    The Sonoma County California tiger salamander population, as well 
as the population in Santa Barbara County, which we listed as 
endangered (65 FR 57242, September 21, 2000), are considered to be the 
most vulnerable of the six populations of the California tiger 
salamander (LSA Associates, Inc. 2001; Shaffer and Trenham 2002). Urban 
development is the primary threat to the Sonoma County California tiger 
salamander. The DPS now occurs in scattered, and increasingly isolated, 
breeding sites within a small portion of its historic range on the 
Santa Rosa Plain in Sonoma County. Five known breeding sites of this 
DPS have been destroyed in the last 2 years. All of the eight known 
remaining breeding sites are distributed in the City of Santa Rosa and 
immediate associated unincorporated areas, an area approximately 8 km 
(5 mi) long by 6 km (4 mi) wide. Within this area and south to the 
Cotati area, there are scattered records of adult salamanders crossing 
roads during the fall and winter rains, and also sporadic instances of 
breeding in roadside ditches and low-quality pools. However, these 
roadside ditches and low-quality pools likely do not represent viable 
breeding sites because they either do not have sufficient ponding 
duration and/or associated uplands for estivation.
    The eight known breeding sites are imperiled by the construction of 
high-density housing, office buildings, roads, and other development. 
The survival and viability of the Sonoma County California tiger 
salamander is directly related to availability of breeding pools with 
hydrological and other factors conducive to the salamander's 
reproduction. There also must be adequate upland acreage, with 
associated small mammal burrows, in the vicinity of the Sonoma County 
California tiger salamander breeding pools to accommodate estivation. 
The Santa Rosa Plain once contained extensive valley oak woods, native 
grasslands, riparian, and vernal pools (1942 aerial photographs on file 
with Dr. Phil Northen at California State University at Sonoma). Vernal 
pools and seasonal wetlands likely were extensive, due to the flat 
terrain, clay soils, and relatively high rainfall (CH2M Hill 1995). 
Based on the topography and habitat type of the lands that have been 
converted to urban development and agriculture on the Santa Rosa Plain, 
the number of breeding ponds, the extent of upland habitats, and the 
quality of the remaining habitats has been greatly reduced since 
Europeans first settled the region.
    The extent of the historic range of the California tiger salamander 
within the Santa Rosa Plain in Sonoma County is uncertain due to 
limited information collected on this population prior to the 1990s 
(Shaffer et al. 1993; Jennings and Hayes 1994). However, based on the 
habitat requirements of the species for low elevation, seasonally 
filled breeding ponds and small rodent burrows, the ecology of the 
taxon, the general trend of urban development into suitable and 
occupied habitat, and other adverse factors affecting the species, we 
believe that it once occupied a more extensive, but still limited area 
within the Santa Rosa Plain.
    A 1990 study of the Santa Rosa Plain found that 25 percent of an 
11,300-ha (28,000-ac) study area had been converted to subdivisions, 
``ranchettes,'' golf courses, and commercial buildings (Waaland et al. 
1990). An additional 17 percent of the study area had been converted to 
agricultural uses. Since 1990, many more acres have been urbanized and 
converted to intensive agriculture, particularly vineyards. Even 
relatively minor habitat modifications, such as construction of roads, 
storm drains, and road curbs that traverse the area between breeding 
and estivation sites, increase habitat fragmentation, impede or prevent 
migration, and result in direct and indirect mortality of California 
tiger salamanders (Mader 1984; S. Sweet, in litt. 1993, 1998; Findlay 
and Houlahan 1996; Launer and Fee 1996; Gibbs 1998). All of the 
remaining known Sonoma County California tiger salamander breeding 
pools are within 450 m (1,476 ft) of roads and residential development, 
and five of the eight remaining viable breeding locations are within 
100 m (328 ft) of major development activities.
Urban Development
    Urban development poses a significant threat to all of the known 
breeding sites of the Sonoma County California tiger salamander. Six of 

[[Page 13509]]

sites are found in and around the former Air Center that is located in 
southwest Santa Rosa. This area contains one of the largest undeveloped 
blocks of land within the city limits of Santa Rosa. Urban development 
is proposed on or near locations containing four of the eight known 
breeding sites in the Santa Rosa area (EIP Associates 1994, 2000). The 
airport was closed and the property sold to the City of Santa Rosa in 
the mid-1980s. The City of Santa Rosa is proposing the majority of the 
area be developed as part of their Southwest Area Plan (EIP Associates 
1994, 2000).
    Urban development of the Santa Rosa area is proceeding rapidly. 
Demographic data obtained from the City of Santa Rosa Housing and 
Community Development Commission indicate that, since 1980, Santa Rosa 
has experienced a greater than 53 percent increase in its population. 
From 1980 until 1997, the number of housing units grew by 66 percent 
from 35,403 units in 1980 to 53,558 units by January 1, 1997 (M. 
Enright, pers. comm., 2001).
    Five known breeding sites were lost within the past 2 years, two of 
which were lost due to commercial development with another lost to 
urban development/housing. In June 2002, a fourth breeding site near 
Cotati was destroyed when the pond was filled for unknown reasons (D. 
Cook, in litt., 2002; L. Davis, pers. comm., 2002). The Cotati location 
was considered highly productive for salamanders (D. Cook, in litt., 
2002). A fifth, and previously unknown, breeding site near Cotati was 
destroyed shortly after the emergency listing went into effect (67 FR 
47726) (D. Wooten, Service, pers. comm., 2002). We were not aware of 
this occurrence at the time the emergency rule was published. 
Salamander larvae were found in a roadside ditch that backed up onto a 
large pool on private property (CNDDB 2002). It is likely this pool 
served as the breeding site for salamanders in this area. This site was 
located in an area where road sightings of tiger salamanders commonly 
occurred in absence of a known breeding site. The pool was drained 
without appropriate authorizations under County of Sonoma ordinances 
(P. Shannin, U.S. Army Corps of Engineers (Corps), pers. comm., 2002; 
P. Stamp, Sonoma County Planning Department, pers. comm., 2002).
Roads and Highways
    California tiger salamanders require a large amount of barrier-free 
landscape for successful migration (Shaffer et al. 1993; Loredo et al. 
1996). Roads and highways are permanent physical obstacles that can 
block the animals from moving to new breeding habitat, or prevent them 
from returning to their breeding ponds or estivation sites. Road 
construction can reduce or completely eliminate the viability of a 
breeding site, and in some cases, larger portions of a metapopulation.
    All the pools at the known extant Sonoma County California tiger 
salamander breeding sites are within 450 m (1,476 ft) of roads of 
various sizes. Findlay and Houlahan (1996) found that roads within 
2,000 m (1.2 mi) of wetlands adversely affected the number of amphibian 
species. At this time, it is still possible for salamanders at breeding 
sites associated with the Air Center to migrate to the FEMA/Broadmore 
North Preserves. A proposed through-street and high-density housing 
will eliminate this migration corridor, leading to fragmentation and 
further isolation of remaining breeding sites. If this planned through-
street and accompanying high-density housing are completed, only three 
breeding sites will remain where salamanders can access more than one 
breeding pool without crossing roads.
    Large numbers of California tiger salamanders at some locations in 
the Central Valley, up to 15 or 20 per mile of road (J. Medeiros, 
Sierra College, pers. comm., 1993), have been killed as they crossed 
roads on breeding migrations (Hansen and Tremper 1993; S. Sweet, in 
litt., 1993). Estimates of losses to automobile traffic range from 25 
to 72 percent of the breeding population for several different 
populations of the species (Twitty 1941; S. Sweet, in litt., 1993; 
Launer and Fee 1996). Curbs and berms as low as 9 to 13 cm (3 to 5 in), 
which allow salamanders to climb onto the road but can restrict or 
prevent their movements off the roads, can turn the roads into sources 
of high mortality (Launer and Fee 1996; S. Sweet, in litt., 1998). 
Automobile traffic along Stony Point Road in western Santa Rosa has 
probably quadrupled in the past 5 years (D. Cook, pers. comm., 2002). 
This was once a moderately used rural road which is now a major route 
for commuter traffic. Between November 21, 2001, and December 5, 2001, 
26 California tiger salamanders were found killed by cars on this road 
between Santa Rosa and Cotati. Fourteen of these dead California tiger 
salamanders were found along Stoney Point Road near Meachum Road (D. 
Cook, pers. comm., 2002). The Engel Preserve is adjacent and north of 
Todd Road. A proposed road widening project along Todd Road would 
likely increase traffic and result in an increased threat of roadkill 
for salamanders migrating between the Engel Preserve and salamander 
estivation habitat south of Todd Road.
Description of the Breeding Sites
    (1) Hall Road Preserve: This 74-ha (183-ac) site is owned by CDFG. 
It is the largest preserved area where the Sonoma County California 
tiger salamander is currently known to occur. It contains two pools 
with ponding levels adequate for successful breeding during drought 
years. This preserve contains seven additional breeding pools that are 
relatively shallow and do not pond water long enough for successful 
breeding in years of moderate to low rainfall. Surveys conducted over 
the past 2 years indicate this preserve does not function as a highly 
productive breeding site (Cook and Northern 2001). The land surrounding 
the preserve is privately owned, and the City of Santa Rosa has issued 
permits for urban development. Urban development has occurred on 
adjacent lands to the east and west, and agriculture to the north of 
the preserve. Exotic predators of the salamander, such as Louisiana 
crayfish (Procrambus clarkii), stickleback fish (Gasterosteus 
aculeatus), and possibly bullfrogs (Rana catesbeiana) are present at 
the Hall Road Preserve.
    (2) FEMA/Broadmore North Preserves: This breeding site consists of 
two properties, the FEMA Preserve and the Broadmore North Preserve. The 
24-ha (59-ac) FEMA Preserve is owned by CDFG and contains one of the 
most productive Sonoma County California tiger salamander breeding 
sites. The 6.5-ha (16-ac) Broadmore North Preserve is a conservation 
area that was set aside as mitigation by the Bellvue School District. 
It is also managed by CDFG. The two breeding sites are contiguous and 
encompass 30 ha (75 ac) containing three breeding pools. The FEMA 
Preserve has two large, deep pools that remain ponded late in the 
season. Salamanders probably breed there during most years. The one 
breeding pool on Broadmore North is shallow and does not contribute 
salamanders to the population in dry years (i.e., there is no 
recruitment) (D. Cook, pers. comm., 2001). While there is no 
hydrological connection between this site and the deeper pools 
contained on the FEMA Preserve, the FEMA Preserve probably allows the 
salamanders at the Broadmore North Preserve the opportunity to breed 
during dry years. Urban development has occurred to the north and east 
sides of the preserves. Although these breeding sites are protected, 
urbanization imperils upland habitats on private land to the east and 
west of them. A new road and housing development on lands adjacent to 

[[Page 13510]]

preserves' western boundaries have been permitted by the City of Santa 
Rosa and are now partially constructed. This new road and construction 
has partially blocked the western migration route between breeding 
pools at the Air Center and the pools at the FEMA and Broadmore North 
preserves. Planned future phases of this project, also permitted by the 
City of Santa Rosa, will totally block migration between the FEMA/
Broadmore North Preserves and the Air Center.
    (3) Engel Preserve: This is a 16-ha (40-ac) privately owned 
preserve that contains approximately 7 ha (18 ac) of wetlands. Three 
pools appear to have ponding levels adequate for salamander breeding in 
normal to dry rainfall years. Sonoma County California tiger 
salamanders were not documented at this site prior to the 2001/2002 
rainy season. Based on the small number of larvae found at this site, 
however, it is likely that there are low numbers of salamanders 
inhabiting this site. Todd Road runs along the southern boundary of 
this site and automobile traffic poses a threat to salamanders 
migrating between the Engel Preserve and estivation sites to the south.
    (4) Northwest Air Center: This breeding site contains one breeding 
pond and is located on private land. Much of the associated upland has 
recently been developed. This site is bordered on the west and north by 
roads subject to heavy traffic from housing developments that have been 
constructed under the City of Santa Rosa's Southwest Area Development 
Plan. Housing has eliminated migration routes to the east and south, 
thus leaving this site as an isolated breeding site with less than 22 
ha (55 ac) of remaining undeveloped upland area and pool with private 
lands surrounding it to the south and east (M. Enright, pers. comm., 
    (5) Southwest Air Center: This breeding site is located on private 
land and contains one breeding pool. The City of Santa Rosa has issued 
permits for a residential development that likely will result in the 
elimination of salamanders at this location. Preparation of this site 
for construction was initiated, but further development has been 
delayed as a result of the emergency listing of this species. The 
salamanders at this location also may utilize the breeding ponds at the 
FEMA/Broadmore North preserves by an existing migration corridor to the 
east. The destruction of this breeding site likely will further isolate 
the animals inhabiting this location. Loss of this breeding site will 
contribute to the overall isolation of the remaining breeding sites.
    (6) North Air Center: There is one breeding pool on this privately 
owned site. Recent residential and commercial developments that border 
the breeding site on three sides severely restrict the potential for 
migration. The City of Santa Rosa has approved residential and road 
projects for this location that will adversely affect the salamanders. 
This site is bordered by houses to the west, a road with high levels of 
automobile traffic to the north, and a corporate park to the east. 
There is a small tract of undeveloped private land to the south. No 
protection exists for the uplands or breeding pool which is located 
directly south of Sebastopol Road. The upland area is about 15 ha (37 
ac). Portions of Sebastopol Road have been widened to four traffic 
lanes, including the construction of storm drains and curbs. The curbs 
likely funnel migrating salamanders into storm drains where they perish 
after being washed into the sewer system. Residential and commercial 
projects currently are under construction in this area. The City of 
Santa Rosa has issued permits for the development of this site, and the 
Corps has requested formal consultation from us for the fill of this 
breeding site. Development plans will also result in the loss of 
estivation habitat. Preparation of this site for construction was 
initiated, but further development has been delayed as a result of the 
emergency listing of this species.
    (7) Wright Avenue: This breeding site is located on private land. 
Approved development described in the City of Santa Rosa's Southwest 
Area Development Plan will isolate this breeding site through increased 
automobile traffic and residential development along Wright and Ludwig 
Avenues. No construction is specifically proposed for this property, 
but no protection exists to prevent the breeding site and associated 
uplands from being developed. This site is on agricultural lands, and 
access has not been allowed for several years. Thus, the condition, or 
even the continued existence of this pool, cannot be confirmed.
    (8) South Ludwig Avenue: This breeding site is located on private 
land, and current threats to the salamanders include increased traffic 
along Ludwig Avenue due to increasing residential development. The 
breeding site and associated uplands are currently not protected from 
potential development. This site is on agricultural lands, and access 
has not been allowed for several years. Thus, the condition, or even 
the continued existence of this pool cannot be confirmed.
Conclusion for Factor A
    Except for the Hall Road Preserve, all of the known breeding sites 
of the Sonoma County California tiger salamander are found on small 
locations in areas being rapidly converted from low-intensity farming, 
cattle grazing, and low-density housing, to high-density housing and 
office buildings. Only three breeding sites (the Hall Road Preserve, 
FEMA/Broadmore North Preserve, and Engel Preserve) have hydrologic 
regimes adequate to provide recruitment for Sonoma County California 
tiger salamanders in normal to dry years. Five of the breeding sites 
are on private property. Two of the breeding sites on private lands are 
on agricultural lands where access for salamander surveys has not been 
allowed in recent years. Thus, it is unknown if these two breeding 
sites still have Sonoma County California tiger salamanders, or if they 
retain hydrological features required for successful salamander 
breeding. Four of the breeding locations associated with the old 
airfield in southwest Santa Rosa are slated for development, which will 
disrupt the hydrology of the surrounding uplands by altering natural 
runoff. If plans for the development of the area in the vicinity of 
these four breeding sites are completed, there will be no migratory 
corridors remaining between any of the currently extant breeding 
    Maintenance of tracts of habitat between breeding sites will likely 
play a pivotal role in maintenance of the Sonoma County California 
tiger salamander metapopulation dynamics. If breeding sites are 
eliminated and the metapopulation becomes so fragmented that 
individuals are unable to disperse between suitable patches of habitat, 
the probability of natural recolonization will not offset the 
probability of extinction. Some of the salamander breeding sites, such 
as the FEMA Preserve/ Broadmore North Preserve and the pools associated 
with the Air Center, are linked to each other by suitable habitat. If 
movements through these linkages are disrupted or precluded (e.g., by 
urban development), then the stability of the metapopulation (i.e., the 
exchange of individuals between breeding sites) will be affected. 
Isolation, whether by geographic distance or ecological factors, will 
prevent the influx of new genetic material, and likely to result in 
inbreeding and eventual extinction (Levin 2002). We believe that the 
Sonoma County California tiger salamander is at risk from increasing

[[Page 13511]]

fragmentation and isolation caused by urban development.

B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    In the past, the larvae of non-native tiger salamanders could 
legally be used as bait by fishermen in California. The extent of the 
use of the Sonoma County California tiger salamander is unknown. The 
California Code of Regulations (2002) now specifies that no salamander 
may be used as bait and excludes the California tiger salamander from a 
list of salamanders, newts, toads, and frogs that may legally be taken 
and possessed under authority of a sportfishing license. The success of 
these present regulations in avoiding or reducing recreational harvest 
of the California tiger salamander is unknown.
    Tiger salamanders are generally thought to make good pets by 
amateur herpetologists (Porras 2002). The Sonoma County California 
tiger salamander does not appear to be particularly popular among 
amphibian and reptile collectors. However, Federal listing could raise 
the value of the species within wildlife trade markets, and increase 
the threat of unauthorized collections above current levels (K. 
McCloud, Special Agent, Service, pers. comm., 2002). Even limited 
interest in the species could pose a serious threat to the DPS.

C. Disease or Predation

    Relatively little is known about the diseases of wild amphibians 
(Alford and Richards 1999). The specific effects of disease on the 
Sonoma County California tiger salamander are not known and the risks 
to the animal have not been determined. However, it is known that mass 
mortalities of amphibians from disease are not uncommon, and may be 
either a natural phenomenon of the biology of species or induced by 
anthropogenic agents (Corn 1994). In California, large numbers of dead 
and dying California tiger salamanders were observed in a pond in the 
Los Alamos Valley in Santa Barbara County, but the cause was not 
determined (S. Sweet, pers. comm., 1998).
    Worthylake and Hovingh (1989) described repeated die-offs of tiger 
salamanders (A. tigrinum) at Desolation Lake in the Wasatch Mountains 
of Utah. Affected salamanders had red, swollen hind legs and vents, and 
widespread hemorrhage of the skin and internal organs. The researchers 
determined that the die-offs were due to infection from the bacterium 
Acinetobacter, or redleg disease. The number of Acinetobacter in the 
lake increased with increasing nitrogen levels as the lake dried. The 
nitrogen was believed to come from both atmospheric deposition and 
waste from sheep grazing in the watershed (Worthylake and Hovingh 
1989). Acinetobacter, which appears to affect amphibians whose immune 
systems have been weakened by stress (Corn 1994) or another bacterial 
infection, was also the suspected cause of larval tiger salamanders 
deaths in Arizona (Collins et al. 1988, as cited in Corn 1994). 
Acinetobacter is common in soil and animal feces.
    Lefcort et al. (1997) found that tiger salamanders raised in 
natural and artificial ponds contaminated with silt were susceptible to 
infection by the water mold Saprolegnia parasitica at a location in 
Georgia. This fungus first appeared on the feet, spread to the entire 
leg, and then infected animals died. Die-offs of western toads (Bufo 
boreas), Cascades frogs (Rana cascadae), and Pacific treefrogs also 
have been associated with Saprolegnia infections (Kiesecker and 
Blaustein 1997). Saprolegnia is widespread in natural waters and 
commonly grows on dead organic material (Wise et al. 1995). Saprolegnia 
ferax outbreaks have been identified as a cause of high amphibian 
embryo mortalities in the Pacific Northwest (Kiesecker et al. 2001).
    Viruses associated with die-offs of tiger and spotted salamanders 
in Maine and North Dakota have been isolated (B. McLean, National 
Wildlife Health Center, in litt., 1998). Also, Jancovich et al. (1997) 
isolated a virus, believed to be an iridovirus, as the primary pathogen 
responsible for a decimating epizootic event affecting the federally 
endangered Sonoran tiger salamander (Ambystoma tigrinum stebbinsi) in 
Arizona. Iridoviruses have recently been implicated as the cause of 
amphibian mass deaths worldwide, with novel iridoviruses identified 
from a number of regions.
    Ranaviruses are often highly virulent and cause systemic infections 
in amphibians. Epizootiology (science that deals with the character, 
ecology, and causes of outbreaks of animal diseases) of ranaviral 
disease in amphibians is poorly understood, but dissemination may be 
partly due to the virus's ability to remain infectious under adverse 
conditions and for prolonged periods. Likely modes of spread of 
amphibian ranaviruses may include use of fishing gear, including boats, 
and through artificial stocking of ponds for recreational fishing. 
Also, water birds have the potential to mechanically transfer the virus 
on their feathers, feet, or bills, or by regurgitation of ingested 
infected material. Some outbreaks of ranaviral disease in tiger 
salamanders have been associated with altered habitats and artificial 
ponds. Due to their highly virulent nature, ranaviruses should be 
considered a potential threat to amphibian populations, especially 
those isolated from previous disease outbreaks (and thus lacking 
specific immunity) and species with low fecundity (Daszak et al. 1999).
    Kiesecker et al. (2001) reported that pathogen outbreaks in 
amphibian populations in the western U.S. may be linked to climate-
induced changes in UV-B light exposure. Their findings indicate that 
climate-induced reductions in water depth at oviposition (laying of 
eggs) sites have caused high mortality of embryos by increasing their 
exposure to UV-B radiation and, consequently, their vulnerability to 
infection. Furthermore, they speculate that climate changes since the 
mid-1970s related to El Ni[ntilde]o/Southern Oscillation cycles and 
elevated sea-surface temperatures could be the precursor for pathogen-
mediated amphibian declines in many regions.
    Pathogen outbreaks have not been documented in Sonoma County 
California tiger salamanders. Nevertheless, disease must be considered 
a potential future population threat because of the relatively small, 
fragmented remaining Sonoma County California tiger salamander breeding 
sites, the many stresses on these sites due to habitat losses and 
alterations, and the many other potential disease-enhancing 
anthropogenic changes which have occurred both inside and outside of 
the range of this DPS. An amphibian pathogen could eliminate one or 
more breeding sites of this animal.
    Predation and competition by introduced or non-native species 
potentially affect all of the known Sonoma County California tiger 
salamander breeding sites. Bullfrogs prey on California tiger 
salamanders (P. Anderson 1968; Lawler et al. 1999). Morey and Guinn 
(1992) documented a shift in amphibian community composition at a 
vernal pool complex, with California tiger salamanders becoming 
proportionally less abundant as bullfrogs increased in number. Lawler 
et al. (1999) found that less than 5 percent of California red-legged 
frog (Rana aurora draytonii) tadpoles survived to metamorphosis when 
raised with bullfrog tadpoles. Moyle (1973) attributed disappearance of 

[[Page 13512]]

California red-legged frogs and foothill yellow-legged frogs (Rana 
mucosa) within the San Joaquin Valley of California to habitat 
alteration coupled with predation and competition from bullfrogs. 
Although bullfrogs are unable to establish permanent breeding 
populations in unaltered vernal pools and seasonal ponds, dispersing 
immature bullfrogs take up residence in such water bodies during winter 
and spring where they prey on native amphibians, including larval 
salamanders (Morey and Guinn 1992; Seymour and Westphal 1994).
    Because bullfrogs are known to travel at least 2.6 km (1.6 mi) from 
one pond to another (Bury and Whelan 1984), they have the potential to 
naturally colonize new areas where they do not currently exist, 
including ponds where Sonoma County California tiger salamanders occur. 
In one study of the eastern San Joaquin Valley, 22 of 23 (96 percent) 
ponds with California tiger salamanders were within the bullfrogs' 
potential dispersal range (Seymour and Westphal 1994). In addition, 
because bullfrogs are still sought within California for sport and 
food, and may be taken without limit under a fishing license, the 
threat of transport for intentional establishment in new locations 
where California tiger salamanders exist or could exist is significant.
    One of the pools at the Hall Road breeding site, and two of the 
pools contained at the FEMA/Broadmore North preserves, are located 
within 46 m (150 ft) of ditches or creek channels known to contain 
bullfrogs or crayfish. Bullfrogs likely occur in Roseland Creek, which 
is near the FEMA/Broadmore North preserve and breeding sites associated 
with the Air Center (D. Cook, pers. comm., 2002). Bullfrogs are likely 
present in ditches that cross the Hall Road Preserve (D. Cook, pers. 
comm., 2002). The direct and indirect evidence thus indicates that non-
native bullfrogs represent a continuing significant threat to the 
persistence of the Sonoma County California tiger salamander.
    Western mosquitofish (Gambusia affinis) are native to central North 
America (watersheds tributary to the Gulf of Mexico) and have been 
introduced throughout the world for mosquito control, including in 
California beginning in 1922. Western mosquitofish now occur throughout 
California wherever the water does not get too cold for extended 
periods, and they are still widely planted throughout the State (Boyce, 
UCD, in litt., 1994) by about 50 local mosquito abatement districts.
    Salamanders may be especially vulnerable to western mosquitofish 
predation due to their fluttering external gills, which may attract 
these visual predators (Graf and Allen-Diaz 1993). Loredo-Prendeville 
et al. (1994) found no California tiger salamanders inhabiting ponds 
containing western mosquitofish. Western mosquitofish prey on other 
amphibian species, such as the California newt (Taricha torosa) 
(Gamradt and Kats 1996) and Pacific treefrog (Goodsell and Kats 1999) 
tadpoles in both field and laboratory experiments, even given the 
optional prey of mosquito larvae (Goodsell and Kats 1999; L. Kats, 
Pepperdine University, pers. comm., 1999). Mosquitofish have also been 
observed ingesting and then spitting out California newt larvae, 
causing severe damage to the newts in the process (Graf and Allen-Diaz 
1993). Given the effects of western mosquito fish on other amphibian 
species, they are likely to have similar effects on California tiger 
salamanders. If they have the same effects, the use of mosquito fish in 
California tiger salamander habitat threatens the persistence of the 
species, especially in the isolated Sonoma County California tiger 
salamander population.
    Other non-native fish have either been directly implicated in 
predation of California tiger salamanders or appear to have the 
potential for such. For example, introductions of sunfish species 
(e.g., largemouth bass (Micropterus salmoides) and bluegill (Lepomis 
macrochirus)), catfish (Ictalurus spp.), and fathead minnows 
(Pimephales promelas) are believed to have eliminated California tiger 
salamanders from several breeding sites in Santa Barbara County 
(Service 2000). Non-native sunfish species, catfish, and bullheads 
(Ameiurus spp.) have been, and still are, widely planted in ponds in 
California to provide for sportfishing. By 1984, the California fish 
fauna included about 50 such transplanted and exotic species, mostly 
from eastern North America origin (Hayes and Jennings 1986). More 
recently, Moyle (2002) estimated that, on average, California is losing 
about one native species or subspecies of fish every 5 to 6 years, and 
gaining an average of one alien species about every 2 years.
    Non-native fish introductions may be responsible for the declines 
of frog species in western North America (Hayes and Jennings 1986). 
Such introduced fish may be a problem for California raids because of 
their specialization for preying on aquatic life (including eggs and 
larvae), and because the affected amphibians may have evolved under 
conditions of limited fish predation, which now increases the impacts 
of such introductions (Hayes and Jennings 1986). We believe the same 
threat applies to the California tiger salamander. Thus, potential 
introduction of such non-native fish species in Sonoma County 
California tiger salamander breeding habitat should be considered a 
threat to the persistence of this DPS.
    The degree to which predation from native fish have affected the 
Sonoma County California tiger salamanders is unknown. For example, 
sticklebacks (Gasterosteus spp.), which have been present in California 
for at least 16 million years, were believed to be the factor 
preventing the Sonoma County California tiger salamander from 
establishing at a site in Sonoma County (Cook and Northen 2001). One 
pool at the Hall Road Preserve appears to have all of the biological 
components for successful California tiger salamander breeding, but has 
a small connector to a drainage ditch containing stickleback. Sonoma 
County California tiger salamanders have never been found at this site, 
and it is suspected that predation of their eggs and larvae by this 
fish is the limiting factor (D. Cook, pers. comm., 2002).
    Non-native and native crayfish (Pacifastacus, Orconectes, and 
Procambarus spp.) apparently prey on California tiger salamanders 
(Shaffer et al. 1993) and may have eliminated some populations 
(Jennings and Hayes 1994). Crayfish prey on California newt eggs and 
larvae, despite toxins produced by these amphibians, and they may be a 
significant factor in the loss of newts from several streams in 
southern California (Gamradt and Kats 1996). These crayfish have been 
found at both the FEMA/Broadmore North and Hall Road Preserves. At the 
FEMA property, crayfish were found in the pool (D. Cook, pers. comm., 
2002). The crayfish likely came from the adjacent Roseland Creek 
Channel. Louisiana crayfish have been found in the ditches that cross 
the Hall Road Preserve, but not at any of the pools known to support 
Sonoma County California tiger salamander populations (D. Cook, pers. 
comm., 2002). The presence of both stickleback and crayfish, along with 
the suspected presence of bullfrogs, could negatively affect Sonoma 
County California tiger salamanders within the Hall Road Preserve.
    California tiger salamanders are also likely preyed on by many 
native species of fish and wildlife. In healthy salamander populations, 
such predation is probably not a significant threat. But when combined 
with other impacts,

[[Page 13513]]

such as predation by non-native species, contaminants, migration 
barriers, or habitat alteration, it may cause a significant decrease in 
population viability. Native predators include herons and egrets, 
western pond turtles (Clemmys marmorata), various garter snakes 
(Thamnophis spp.), larger California tiger salamanders, larger 
spadefoot toads (Scaphiopus hammondii), and California red-legged frogs 
(M. Peters, Service, in litt., 1993; Hansen and Tremper 1993). In 
Arizona, larval tiger salamanders are preyed upon by adult predaceous 
diving beetles (Dytiscus dauricus) (Holomuzki 1986), and turkey 
vultures (Carthartes aura) have been observed feeding on larval or 
adult tiger salamanders (Duncan 1999).

D. The Inadequacy of Existing Regulatory Mechanisms

    The primary cause of the decline of the Sonoma County California 
tiger salamander is the loss, degradation, and fragmentation of habitat 
due to human activities. Federal, State, and local laws have been 
insufficient to prevent past and ongoing losses of the limited habitat 
of the Sonoma County California tiger salamander.
    Clean Water Act. Under section 404 of the Clean Water Act (CWA) (33 
U.S.C. 1344 et seq.), the U.S. Army Corps of Engineers (Corps) 
regulates the discharge of fill material into waters of the United 
States, including wetlands. Section 404 regulations require applicants 
to obtain a permit for projects that involve the discharge of fill 
material into waters of the United States, including wetlands. However, 
normal farming activities are exempt under the CWA and do not require a 
permit (53 FR 20764; Robert Wayland III, Environmental Protection 
Agency (EPA), in litt., 1996). Projects that are subject to regulation 
may qualify for authorization to place fill material into headwaters 
and isolated waters, including wetlands, under several nationwide 
permits. The use of nationwide permits by an applicant or project 
proponent is normally authorized with minimal environmental review by 
the Corps. No activity that is likely to jeopardize the continued 
existence of a threatened or endangered species, or that is likely to 
destroy or adversely modify designated critical habitat of such 
species, is authorized under any nationwide permit. An individual 
permit may be required by the Corps if a project otherwise qualifying 
under a nationwide permit would have greater than minimal adverse 
environmental impacts.
    Recent court cases may further limit the Corps' ability to utilize 
the CWA to regulate the fill or discharge of fill or dredged material 
into the aquatic environment within the current range of the Sonoma 
County California tiger salamander (Solid Waste Agency of Northern Cook 
County v. U.S. Army Corps of Engineers, 531 U.S. 159 (2001) (SWANCC)). 
The effect of SWANCC on Federal regulation of activities in wetlands in 
the area of the Sonoma County California tiger salamander has recently 
become clear by the Corps' failure to assert its jurisdiction over fill 
of several wetlands within the range of the Sonoma County California 
tiger salamander. In a letter from the Corps dated March 8, 2002, 
concerning the fill of 0.18 ha (0.45 ac) of seasonal wetlands southwest 
of the intersection of Piner and Marlow Roads (Corp File Number 
19736N), the Corps referenced the SWANCC decision and reiterated that 
the subject wetlands were not ``waters of the United States'' because 
they were: (1) Not navigable waters; (2) not interstate waters; (3) not 
part of a tributary system to 1 or 2; (4) not wetlands adjacent to any 
of the foregoing; and (5) not an impoundment of any of the above. The 
letter further stated that the interstate commerce nexus to these 
particular waters is insufficient to establish CWA jurisdiction and, 
therefore, not subject to regulation by the Corps under section 404 of 
the CWA. The Corps also cited the SWANCC decision as their reasoning 
for not taking jurisdiction over fill of Sonoma County California tiger 
salamander breeding pools at the recently constructed South Sonoma 
Business Park.
    When on- or off-site mitigation is required by the Corps as a 
condition of a section 404 permit to fill certain wetlands, there is 
often low probability that affected Sonoma County California tiger 
salamander habitat values, if any, would actually be compensated and 
replaced by the ensuing mitigation action(s). A 1994 Service study of 
selected wetlands re-creation projects in California authorized through 
the section 404 program found deficiencies in both compliance and 
performance of the re-created wetlands (Santa Rosa Plain Vernal Pool 
Ecosystem Preservation Plan 1995). There was evidence that, of all the 
proposed mitigation, half of the sites were meeting less than 75 
percent of the mitigation conditions and our goal for ``in-kind'' 
replacement was not being met (DeWeese 1994). Other recent studies have 
produced similar results. In addition, most wetland re-creation efforts 
in California to date have been directed at the wetlands themselves and 
have not adequately addressed the upland and other related needs of 
California tiger salamanders.
    Semlitsch (1998) examined published literature for six species of 
pond-breeding ambystomatid salamanders from five States and concluded 
that a buffer zone encompassing 95 percent of a given population would 
need to extend 263 m (534 ft) from a wetland's edge into surrounding 
terrestrial habitat in order to give adequate protection. More 
recently, Trenham (2001), although cautioning that essential 
terrestrial habitats and buffer requirements are still relatively 
poorly understood, concluded that plans to maintain local populations 
of California tiger salamanders should include pond(s) surrounded by 
buffers at least 173 m (567 ft) wide of terrestrial habitat occupied by 
burrowing mammals. Management plans that focus only on preserving ponds 
or wetlands--without consideration for associated terrestrial habitat--
are likely to fail to maintain viable amphibian populations (Marsh and 
Trenham 2001). However, even with inclusion of terrestrial habitat 
buffers, recent studies have demonstrated that restored wetlands are 
often still only partially successful in recolonization by the full 
amphibian assemblages being targeted for restoration (Lehtinen and 
Galatowitsch 2001; Pechmann et al. 2001). Successful compensatory 
mitigation for losses of California tiger salamander pool and pond 
habitat due to filling would also require the connectivity of the 
restoration site to other pools and ponds (Gibbs 1998; Lehtinen et al. 
1999; Trenham et al. 2001; Marsh and Trenham 2001). Pond isolation may 
be an important consideration in disturbed environments where inter-
pond dispersal is impeded by barriers such as roads and urban 
development (Marsh and Trenham 2001). The California tiger salamander 
may also require large preserves to maintain viable breeding 
populations and to allow recolonizations from natural and anthropogenic 
local extirpations (P. Northen, in litt., 2001).
    Three federally endangered plants, Sonoma sunshine (Blennosperma 
bakeri), Sebastopol meadowfoam (Limnanthes vinculans), and Burke's 
goldfields (Lasthenia burkei) occur on the Santa Rosa Plain of Sonoma 
County in the vicinity of the Sonoma County California tiger 
salamander. However, little overlap occurs between the viable breeding 
sites of this species and these federally listed vernal pool species. 
Any Corps consultation requirement for fill

[[Page 13514]]

of pools on the Santa Rosa Plain would be triggered by the listed 
plants. Since the salamander and the federally listed plants do not 
substantially overlap, salamander breeding pools are unlikely to be 
protected by presence of the plants or their habitat. Furthermore, even 
if breeding pools of this animal are avoided due to the presence of a 
federally listed plant species, this protection may only extend to the 
pool itself with a small upland buffer. Since Sonoma County California 
tiger salamanders spend up to 80 percent of their life in small mammal 
burrows in upland habitats surrounding breeding pools, the protection 
of the pool itself, with concurrent loss of uplands surrounding the 
pool, would still result in the loss of local Sonoma County California 
tiger salamander breeding sites.
    We conclude that regulation of wetlands filling by the Corps under 
section 404 of the CWA is inadequate to protect the Sonoma County 
California tiger salamander from further decline. Section 404 
implementation fails to prevent losses of numerous small wetlands in 
California that may support California tiger salamander breeding. 
Section 404 does not regulate the continuing losses of California tiger 
salamander terrestrial habitat (except to the extent certain 
agricultural activities may be regulated). When authorized fills under 
section 404 do result in compensatory mitigation for wetlands losses, 
it is unlikely that California tiger salamander habitat losses at 
specific fill sites can, and will be, fully and successfully mitigated.
    Since 1994, the CDFG recognizes the California tiger salamander as 
a ``species of special concern'' by the CDFG. More recently, the 
California tiger salamander has been placed on the State's list of 
protected amphibians, which means that it cannot be taken without a 
special permit issued for scientific collecting or research. Also, as 
stated earlier, the California Code of Regulations (2002) specifies 
California tiger salamanders can no longer be taken, possessed, or used 
for fishing bait. However, any more stringent protection of California 
tiger salamanders or their habitat, as would be provided under a CESA 
listing or designation as a Fully Protected species by CDFG, is 
    CDFG recognizes the importance of California tiger salamander 
conservation at the local population level, and routinely considers and 
recommends actions to mitigate potential adverse effects to the species 
during its review of development proposals. However, CDFG's primary 
regulatory venue is under CEQA (Public Resources Code Sec. 21000-
21177). CEQA has been a variable, and apparently inadequate, regulatory 
mechanism for providing protection to the California tiger salamander 
and its habitat.
    The California Environmental Quality Act (CEQA) (Public Resources 
Code Sec. 21000-21177) requires a full disclosure of the potential 
environmental impacts of proposed projects. The public agency with 
primary authority or jurisdiction over a project for which it has 
discretion is designated as the lead agency and is responsible for 
conducting a review of the project and consulting with the other 
agencies concerned with the resources affected by the project. Section 
15065 of the CEQA Guidelines, as amended, requires a finding of 
significance if a project has the potential to ``reduce the number or 
restrict the range of a rare or endangered plant or animal.'' Once 
significant effects are identified, the lead agency has the option of 
requiring mitigation for effects through changes in the project or to 
decide that overriding considerations make mitigation infeasible (CEQA 
Sec. 21002). In the latter case, projects may be approved that cause 
significant environmental damage, such as destruction of listed 
endangered species and/or their habitat. Protection of listed species 
through CEQA is, therefore, dependent upon the discretion of the lead 
agency involved, although ``overriding considerations'' are 
infrequently found.
    However, neither CEQA nor CDFG provide completely effective 
regulatory mechanisms for reducing or eliminating the introduction of 
non-native fish into Sonoma County California tiger salamander habitat. 
For example, there is no State regulation of non-native fish stocking 
into ponds and waters occupied by Sonoma County California tiger 
salamanders. Agencies and individuals may purchase fish from CDFG-
licensed breeders and stock into such waters an array of non-native 
sunfish, catfish, and other fish for recreational fishing. Similarly, 
there is no State regulation of western mosquitofish stocking into 
Sonoma County California tiger salamander breeding ponds and waters. In 
addition, lethal control of small mammals in places where small mammal 
burrows occur may affect the survival of the California tiger 
salamander because the practice is not State-regulated, and is still 
widely and commonly practiced throughout the California tiger 
salamander's range. The burrows of these small mammals are used by 
California tiger salamanders to estivate during the summer and fall 
months of the year.
    We are not aware of any specific county or city ordinances or 
regulations that provide protection for the Sonoma County California 
tiger salamander. Sonoma County recently has begun applying regulatory 
oversight to conversions to vineyards, which may indirectly benefit the 
species. This oversight is resulting in requirements for full-scale 
environmental analyses, restrictions on the steepness of slopes onto 
which vineyards may be established, and requirements for erosion 
control plans and measures. However, it is unclear if the restriction 
on planting vineyards on steep slopes will result in more pressures to 
cultivate flat areas that contain habitat for the Sonoma tiger 

E. Other Natural or Manmade Factors Affecting Its Continued Existence

    Several other factors, including contaminants, ground squirrel and 
gopher control, mosquito control, hybridization with non-native 
salamanders, competition with introduced species, and decreased 
population viability may have negative effects on California tiger 
salamanders and their aquatic and upland habitats.
    Like most amphibians, California tiger salamanders inhabit both 
aquatic and terrestrial habitats at different stages in their life 
cycle, and are likely exposed to a variety of pesticides and other 
chemicals throughout their range. They are extremely sensitive to these 
pollutants due to their highly permeable skin, which can rapidly absorb 
pollutant substances (Blaustein and Wake 1990). Toxins at lower than 
lethal levels may still have adverse effects, such as causing 
abnormalities in larva and behavioral anomalies in adults, both of 
which could eventually lead to lethal effects (Hall and Henry 1992; 
Blaustein and Johnson 2003).
    California tiger salamanders also could die from starvation by the 
loss of their prey-base. Hydrocarbon and other contaminants from oil 
production and road runoff; the application of numerous chemicals for 
agricultural production; roadside maintenance activities; urban/
suburban landscaping applications; and rodent and vector control 
programs may all have negative effects on tiger salamander populations, 
as detailed below.
    Road mortality is not the only risk factor associated with roads, 
as oil and other contaminants in runoff have been

[[Page 13515]]

detected in adjacent ponds and linked to die-offs and deformities in 
California tiger salamanders and spadefoot toads, and die-offs of 
invertebrates that form most of both species' prey base (S. Sweet, in 
litt,. 1993). Lefcort et al. (1997) found that oil had limited direct 
effects on 5-week-old marbled (Ambystoma opacum) and tiger salamanders 
(A. t. tigrinum). However, salamanders from oil-contaminated natural 
ponds metamorphosed earlier at smaller sizes, and those from oil-
contaminated artificial ponds had slower growth rates, than larvae 
raised in non-contaminated ponds. Their studies did not address effects 
on eggs and early larval stages, where the effects may be more 
    Hatch and Burton (1998) and Monson et al. (1999) investigated the 
effects of one component of petroleum products and urban runoff 
(fluoranthene, a polycyclic aromatic hydrocarbon) on spotted 
salamanders (A. maculatum), northern leopard frogs (Rana pipiens), and 
African clawed frogs (Xenopus laevis). In laboratory and outdoor 
experiments, using levels of the contaminant comparable to those found 
in service stations and other urban runoff, the researchers found 
reduced survival and growth abnormalities in all species. The effects 
were worse when the larvae were exposed to the contaminant under 
natural levels of sunlight, rather than in the laboratory under 
artificial light.
    In Sonoma County, there are a number of records of California tiger 
salamanders using roadside ditches. Many are in areas where there are 
no known breeding ponds, and these animals are utilizing the only 
marginal habitat remaining. Also, many pools in these areas have likely 
been destroyed, leaving these marginal sites as the only option for 
breeding. In light of this increased urbanization occurring in Sonoma 
County, along with concurrent increases in traffic, the risk factor 
associated with contaminants in runoff likely will increase in both 
roadside ditches and across the general landscape.
Agricultural and Landscaping Contaminants
    In Sonoma County, over 1.4 million kilograms (3.1 million pounds) 
of agricultural chemicals were used in 2000 on grapes, apples, rights 
of way, structural pest control, and landscape maintenance (California 
Department of Pesticide Regulation 2000, Internet Website). Chemical 
use occurring on or near tiger salamander breeding sites in Sonoma 
County is primarily associated with rights of way, structural pest 
control, and landscape maintenance. These chemicals included metam-
sodium, methyl bromide, mancozeb, petroleum oil, phosmet, chlorpyrifos, 
pendimethalin, parathion, paraquat dichloride, fosetyl-aluminum, 
acephate, cryolite, and malathion, some of which are extremely toxic to 
aquatic organisms, such as amphibians and the organisms on which they 
    Even if toxic or detectable amounts of pesticides are not found in 
breeding ponds or groundwater, salamanders may still be affected, 
particularly when chemicals are applied during the migration and 
dispersal seasons. All but one of the remaining eight documented 
salamander breeding sites in Sonoma County may be directly or 
indirectly affected by toxic landscaping chemicals due to the presence 
of housing developments within their drainage basins. Sparling et al. 
(2001) examined pesticide usage and amphibian (Rana and Bufo spp.) 
population declines in California and found that pesticides have been 
instrumental in declines of these species. Davidson et al. (2001, 2002) 
also found a strong relationship between the declines in four 
California native ranid species and upwind agriculture, specifically 
the use of agrochemicals upwind of ranid populations that are not 
directly impacted by habitat destruction. However, Davidson et al. 
(2002) were unable to find a significant overall relationship between 
upwind agriculture and the California tiger salamander's decline.
Rodent Control
    California tiger salamanders spend much of their lives estivating 
in underground retreats, typically in the burrows of ground squirrels 
and gophers (Loredo et al. 1996; Trenham 1998a). Dave Cook (pers. 
comm., 2001) found that pocket gopher burrows are most often used by 
California tiger salamanders in Sonoma County. Both of these species 
are classified as non-game mammals by CDFG, which means that if pocket 
gophers or ground squirrels are found to be injuring growing crops or 
other property, including garden and landscape plants, they may be 
controlled at any time and in any legal manner by the owner or the 
tenant of the premises (University of California Integrated Pest 
Management (UCIPM) internet website 2002).
    Legal methods of pocket gopher control include trapping, 
strychnine-treated grain bait, and anticoagulant baits. Poisoned grains 
(anticoagulant baits) are the most common method used to control ground 
squirrels around homes and other areas where children, pets, and 
poultry are present (UCIPM internet website 2002; Jon Shelgrin, 
California Department of Pesticide Regulation, pers. comm., 2002). Zinc 
phosphide is highly toxic to freshwater fish and to non-target mammals 
(Extension Toxicology Network (EXOTONET) 1996). Zinc phosphide, a 
rodenticide and restricted material, turns into phosgene gas, which is 
toxic to the rodents once ingested. There is little risk of California 
tiger salamanders ingesting any of these baits; however, the use of 
these grains may impact the California tiger salamanders indirectly if 
washed into burrows or ponds used by the species.
    Two of the most commonly used rodenticides, chlorophacinone and 
diphacinone, are anticoagulants that cause animals to bleed to death. 
These chemicals can be absorbed through the skin and are considered 
toxic to fish and wildlife (U. S. Environmental Protection Agency 1985; 
EXOTONET 1996). These two chemicals, along with strychnine, are used in 
Sonoma County to control rodents (R. Thompson, Science Applications 
International Corporation, in litt., 1998). Although the effects of 
these poisons on California tiger salamander have not been assessed, 
any uses in close proximity to occupied California tiger salamander 
habitat could have various direct and indirect toxic effects. Gases, 
including aluminum phosphide, carbon monoxide, and methyl bromide, are 
used in rodent fumigation operations and are introduced into burrows by 
either using cartridges or by pumping. When such fumigants are used, 
animals inhabiting the fumigated burrow are killed (Salmon and Schmidt 
    In addition to possible direct effects of rodent control chemicals, 
control programs probably have an adverse indirect effect on California 
tiger salamander populations. Control of ground-burrowing rodents could 
significantly reduce the number of burrows available for use by the 
Sonoma County California tiger salamander (Loredo-Prendeville et al. 
1994). All but one of the remaining Sonoma County California tiger 
salamander breeding locations exist in areas that are likely to 
experience a heightened degree of rodent control due to landscaping 
concerns surrounding residential developments. Because the burrow 
density required to support Sonoma County California tiger salamanders 
in an area is not known, the loss of burrows as a result of control 
programs cannot be quantified at this time. However, Shaffer et al. 
(1993) stated that rodent control programs may be responsible for the 
lack of California

[[Page 13516]]

tiger salamanders in some areas. Active ground squirrel colonies 
probably are needed to sustain tiger salamanders because inactive 
burrow systems become progressively unsuitable over time. Loredo et al. 
(1996) found that burrow systems collapsed within 18 months following 
abandonment by or loss of the ground squirrels. Although the 
researchers found that California tiger salamanders used both occupied 
and unoccupied burrows, they did not indicate that the salamanders used 
collapsed burrows. Rodent control programs must be analyzed and 
implemented carefully in California tiger salamander habitat so the 
persistence of the animals is not threatened. One of the remaining 
Sonoma County California tiger salamander sites is currently occupied 
by cattle. Most owners of livestock seek to eliminate ground squirrel 
burrows because of the threat of cows (Bos bos) breaking their legs if 
they accidentally step into a burrow.
Mosquito Control
    In addition to the use of western mosquitofish, a common chemical 
method of mosquito control in California involves the use of 
methoprene. Methoprene is an insect hormone mimic that increases the 
level of juvenile hormone in insect larvae and disrupts the molting 
process. Lawrenz (1984, 1985) found that methoprene (Altosoid SR-10) 
retarded the development of selected crustacea that had the same 
molting hormones (i.e., juvenile hormone) as insects, and anticipated 
that the same hormone may control metamorphosis in other arthropods. 
Because the success of many aquatic vertebrates relies on an abundance 
of invertebrates in temporary wetlands, any delay in insect growth 
could reduce the numbers and density of prey available (Lawrenz 1984, 
1985). The use of methoprene could have an indirect adverse effect on 
California tiger salamanders by reducing the availability of prey.
    In more recent studies, methoprene did not cause increased 
mortality of gray treefrog (Hyla versicolor) tadpoles (Sparling and 
Lowe 1998). However, it caused reduced survival rates and increased 
malformations in northern leopard frogs (Rana pipiens) (Ankley et al. 
1998) and increased malformations in southern leopard frogs (R. 
utricularia) (Sparling 1998). Blumberg et al. (1998) correlated 
exposure to methoprene with delayed metamorphosis and high mortality 
rates in northern leopard and mink (R. septentrionalis) frogs. 
Methoprene appears to have both direct and indirect effects on the 
growth and survival of larval amphibians.
Road-Crossing Mortality
    Although no systematic studies road-crossing mortality of the 
Sonoma County California tiger salamander have been conducted, it is 
known that significant numbers of California tiger salamanders in other 
portions of the species' range are killed by vehicular traffic while 
crossing roads (Hansen and Tremper 1993; S. Sweet, in litt., 1993; J. 
Medeiros, pers. comm., 1993). For example, during a 1-hour period on a 
road bordering Lake Lagunita on the Stanford University campus, 45 
California tiger salamanders were collected, 28 of which had been 
killed by cars (Twitty 1941). More recently, during one 15-day period 
in 2001 at a Sonoma County location, 26 road-killed California tiger 
salamanders were found (D. Cook, pers. comm., 2002). Overall breeding 
population losses of California tiger salamanders due to road kills 
have been estimated to be between 25 and 72 percent (Twitty 1941; S. 
Sweet, in litt., 1993; Launer and Fee 1996). Mortality may be increased 
by associated roadway curbs and berms as low as 9 to 12 cm (3 to 5 in), 
which allow California tiger salamanders access to roadways but prevent 
their exit from them (Launer and Fee 1996; S. Sweet, in litt., 1998). 
In a recent study along a 1.1 km (0.7 mi) high-vehicular-use (21,450 
vehicles per day) section of the Trans-Canadian Highway in Alberta, 
Canada, Clevenger et al. (2001) recorded 183 road-killed tiger 
salamanders (Ambystoma species) in 30 days and concluded it was likely 
that very few of the local population had survived.
Hybridization With Non-native Salamanders
    Hybrids between the California tiger salamander and the non-native 
tiger salamander (Ambystoma tigrinum) have been documented elsewhere in 
the range of Ambystoma californiese (Shaffer and Trenham 2002). 
Introduced salamanders may out-compete the California tiger salamander, 
or interbreed with the natives to produce hybrids that may be less fit 
and adapted to the California climate, or are not reproductively viable 
past the first or second generations (Bury and Lukenbach 1976; Shaffer 
et al. 1993). More recent evidence suggests that the hybrids are 
viable, and that they breed with California tiger salamanders (Shaffer 
and Trenham 2002). Over time, a population of a species could become 
genetically indistinguishable from a larger population of an 
introgressing species such that the true genotype (the genetic 
constitution of an individual or group) of the lesser species no longer 
exists (Levin 2002). The loss of any breeding sites of the Sonoma 
County California tiger salamander due to hybridization with, or 
competition from, introduced species is of serious concern.
Livestock Grazing
    Light-to-moderate livestock grazing is generally thought to be 
compatible with California tiger salamanders, provided the grazed areas 
do not also have intensive burrowing rodent control efforts (T. Jones, 
University of Michigan, in litt., 1993, S. Sweet, pers. comm. 1998). By 
keeping vegetation shorter, grazing may make areas more suitable for 
ground burrowing rodents whose burrows are essential to Sonoma County 
California tiger salamanders. However, heavy grazing, or heavy use of 
certain pools and ponds for livestock watering, can clearly have 
adverse effects on the species. Melanson (in litt., 1993) noted that, 
although vernal pool species continued to reproduce under a November-
to-April grazing regime, California tiger salamanders were either 
absent or found in low numbers in portions of pools heavily trampled by 
cattle. Repeated trampling of pond edges by cattle can increase the 
surface area of a pond, and may increase water temperature and 
evaporation rate, thus reducing the amount of time the pond contains 
water (S. Sweet, pers. comm., 1998).
    Reduction in water quality caused by livestock excrement may 
negatively affect the California tiger salamander by increasing 
nitrogen and silt levels. High nitrogen levels associated with 
bacterial blooms, lowered dissolved oxygen (Worthylake and Hovingh 
1989), and silt have been associated with fatal fungal infections 
(Lefcort et al. 1997), as discussed earlier under Factor C.
    However, grazing generally is compatible with the continued use of 
rangelands by the California tiger salamander as long as intensive 
control programs for burrowing rodents are not implemented on such 
areas, and grazing is not excessive (T. Jones, in litt., 1993).
Population Size
    The low numbers of Sonoma County California tiger salamander make 
it vulnerable to risks associated with small, restricted populations. 
The elements of risk that are amplified in very small populations 
include: (1) The impact of high death rates or low birth rates; (2) the 
effects of genetic drift (random fluctuations in gene frequencies) and 
inbreeding (mating among close relatives); and (3) deterioration in 
environmental quality

[[Page 13517]]

(Gilpin and Soule 1986). Genetic drift and inbreeding may lead to 
reductions in the ability of individuals to survive and reproduce 
(i.e., reductions in fitness) in small populations. In addition, 
reduced genetic variation in small populations may make any species 
less able to successfully adapt to future environmental changes 
(Shaffer 1981, 1987; Noss and Cooperrider 1994; Primack 1998).

Conclusion for the Five Factors

    In making this determination, we have carefully assessed the best 
scientific and commercial information available regarding the past, 
present, and future threats faced by the Sonoma County California tiger 
salamander. As discussed in the Summary of Factors Affecting the 
Species above, this DPS faces a number of threats. The most 
overwhelming threat is from continuing habitat destruction, 
degradation, and fragmentation. Secondary threats exist from predation 
and competition from introduced exotic species; possible commercial 
overutilization; disease; hybridization with non-native salamanders; 
various chemical contaminants; road-crossing mortality; rodent control 
operations, and the species' small remaining population. The various 
primary and secondary threats are not currently being offset by 
existing Federal, State, or local regulatory mechanisms. The Sonoma 
County California tiger salamander also is vulnerable to chance 
environmental or demographic events, to which small populations are 
particularly vulnerable. The combination of its biology and specific 
habitat requirements makes the animal highly susceptible to random 
events, such as drought, disease, and other occurrences. Such events 
are not usually a concern until the number of breeding/estivation sites 
or geographic distribution become severely limited, as is the case with 
the Sonoma County California tiger salamander.
    Because the Sonoma County DPS of the California tiger salamander 
has been reduced to only eight known breeding sites, and all of them 
are subject to various immediate, ongoing, and future threats as 
outlined above, we find that the species is in imminent danger of 
extinction throughout all or a significant portion of its range and 
warrants immediate protection under the Act. The survival of this DPS 
now depends on protecting as many breeding sites and their associated 
upland habitats from further degradation and destruction as possible. 
The remaining breeding sites are vulnerable to loss from random natural 
or human-caused events unless sufficient habitat can be protected and 
the metapopulations increased in size.

Critical Habitat

    Critical habitat is defined in section 3 of the Act as the--(i) 
specific areas within the geographical area occupied by a species, at 
the time it is listed in accordance with the Act, on which are found 
those physical or biological features (I) essential to the conservation 
of the species, and (II) that may require special management 
considerations or protection, and (ii) specific areas outside the 
geographical area occupied by the species at the time it is listed in 
accordance with the provisions of section 4 of the Act, upon a 
determination by the Secretary that such areas are essential for the 
conservation of the species. ``Conservation'' means the use of all 
methods and procedures needed to bring the species to the point at 
which listing under the Act is no longer necessary.
    Section 4(a)(3) of the Act and implementing regulations (50 CFR 
424.12) require that, to the maximum extent prudent and determinable, 
the Secretary of the Interior (Secretary) designate critical habitat at 
the time the species is determined to be endangered or threatened. Our 
implementing regulations (50 CFR 424.12(a)) state that critical habitat 
is not determinable if information sufficient to perform the required 
analysis of impacts of the designation is lacking, or if the biological 
needs of the species are not sufficiently well known to allow 
identification of an area as critical habitat. Section 4(b)(2) of the 
Act requires us to consider economic and other relevant impacts of 
designating a particular area as critical habitat on the basis of the 
best scientific data available. The Secretary may exclude any area from 
critical habitat if she determines that the benefits of such exclusion 
outweigh the conservation benefits, unless to do so would result in the 
extinction of the species. In the absence of a finding that critical 
habitat would increase threats to a species, if any benefits would 
derive from critical habitat designation, then a prudent finding is 
warranted. In the case of this species, designation of critical habitat 
may provide some benefits.
    The primary regulatory effect of critical habitat is the section 7 
requirement that agencies refrain from taking any action that destroys 
or adversely modifies critical habitat. While a critical habitat 
designation for habitat currently occupied by this species would not be 
likely to change the section 7 consultation outcome because an action 
that destroys or adversely modifies such critical habitat would also be 
likely to result in jeopardy to the species, there may be instances 
where section 7 consultation would be triggered only if critical 
habitat is designated. Examples could include unoccupied habitat or 
occupied habitat that may become unoccupied in the future. Designating 
critical habitat may also produce some educational or informational 
benefits. Therefore, designation of critical habitat for the Sonoma 
County California tiger salamander is prudent.
    However, our budget for listing activities is currently 
insufficient to allow us to immediately complete all the listing 
actions required by the Act. Not designating critical habitat at this 
time allows us to provide the necessary protections needed for the 
conservation of the species without further delay. This is consistent 
with section 4(b)(6)(C)(i) of the Act, which states that final listing 
decisions may be issued without critical habitat designations when it 
is essential that such determinations be promptly published. The 
legislative history of the 1982 Act amendments also emphasized this 
point: ``The Committee feels strongly, however, that, where biology 
relating to the status of the species is clear, it should not be denied 
the protection of the Act because of the inability of the Secretary to 
complete the work necessary to designate critical habitat * * * . The 
committee expects the agencies to make the strongest attempt possible 
to determine critical habitat within the time period designated for 
listing, but stresses that the listing of species is not to be delayed 
in any instance past the time period allocated for such listing if the 
biological data is clear but the habitat designation process is not 
complete'' (H.R. Rep. No. 97-567 at 20 (1982)). We will prepare a 
critical habitat designation in the future when our available resources 
    We will protect the Sonoma County California tiger salamander and 
its habitat through section 7 consultations to determine whether 
Federal actions are likely to jeopardize the continued existence of the 
species, through the recovery process, through enforcement of take 
prohibitions under section 9 of the Act, and through the section 10 
process for activities on non-Federal lands with no Federal nexus.

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened under the Act include recognition, recovery actions, 
requirements for Federal protection, and prohibitions against certain 

[[Page 13518]]

Recognition through listing encourages conservation actions by Federal, 
State, and local agencies. The Act provides for possible land 
acquisition and cooperation with the State and requires that recovery 
actions be carried out for listed species. We discuss the protection of 
Federal agencies, considerations for protection and conservation 
actions, and the prohibitions against taking and harm for the Sonoma 
County California tiger salamander, in part, below.
    Section 7(a) of the Act, as amended, requires Federal agencies to 
evaluate their actions with respect to any species that is proposed to 
be listed or is listed as endangered or threatened, and with respect to 
its critical habitat, if any is being designated. Regulations 
implementing this interagency cooperation provision of the Act are 
codified at 50 CFR part 402. Federal agencies are required to confer 
with us informally on any action that is likely to jeopardize the 
continued existence of a proposed species, or result in destruction or 
adverse modification of proposed critical habitat. If a species is 
listed subsequently, section 7(a)(2) requires Federal agencies to 
ensure that activities they authorize, fund, or carry out are not 
likely to jeopardize the continued existence of such a species or to 
destroy or adversely modify its critical habitat. If a Federal agency 
action may affect a listed species or its critical habitat, the 
responsible Federal agency must enter into formal consultation with us. 
Federal agency actions that may affect the Sonoma County California 
tiger salamanders and may require consultation with us include, but are 
not limited to, those within the jurisdiction of the Corps, and Federal 
Highway Administration (FHA).
    We believe that protection and recovery of the Sonoma County 
California tiger salamander will require reduction of the threats from 
destruction and degradation of wetland and associated upland habitats 
due to urban development, exotic predators, unnecessary ground squirrel 
and gopher control, and road construction. Threats from collection and 
pesticide drift also must be reduced. These threats should be 
considered when management actions are taken in habitats currently and 
potentially occupied by the Sonoma County California tiger salamander, 
and areas deemed important for dispersal and connectivity or corridors 
between known locations of this species. Monitoring also should be 
undertaken for any management actions or scientific investigations 
designed to address these threats or their impacts.
    Listing the Sonoma County California tiger salamander provides for 
the development and implementation of a recovery plan for the DPS. This 
plan will bring together Federal, State, and regional agency efforts 
for the conservation of the DPS. A recovery plan will establish a 
framework for agencies to coordinate their recovery efforts. The plan 
will set recovery priorities and estimate the costs of the tasks 
necessary to accomplish the priorities. It also will describe the site-
specific actions necessary to achieve conservation and survival of the 
    Listing also will require us to review any actions that may affect 
the Sonoma County California tiger salamander for lands and activities 
under Federal jurisdiction, State plans developed pursuant to section 6 
of the Act, scientific investigations of efforts to enhance the 
propagation or survival of the animal, pursuant to section 10(a)(1)(A) 
of the Act, and habitat conservation plans prepared for non-Federal 
lands and activities pursuant to section 10(a)(1)(B) of the Act.
    Federal agencies with management responsibility for the Sonoma 
County California tiger salamander include the Service, in relation to 
the issuance of section 10(a)(1)(A and B) permits for habitat 
conservation plans and other programs. Occurrences of this species 
could potentially be affected by projects requiring a permit from the 
Corps under section 404 of the CWA. The Corps is required to consult 
with us on applications they receive for projects that may affect 
listed species. Highway construction and maintenance projects that 
receive funding from the FHA would be subject to review under section 7 
of the Act. In addition, activities that are authorized, funded, or 
administered by Federal agencies on non-Federal lands will be subject 
to section 7 review.
    The Act and implementing regulations found at 50 CFR 17.21 set 
forth a series of general prohibitions and exceptions that apply to all 
endangered wildlife. These prohibitions, codified at 50 CFR 17.21, in 
part make it illegal for any person subject to the jurisdiction of the 
United States to take (includes harass, harm, pursue, hunt, shoot, 
wound, kill, trap, capture, or collect; or attempt any such conduct), 
import, export, transport in interstate or foreign commerce in the 
course of commercial activity, or sell or offer for sale in interstate 
or foreign commerce any listed species. It also is illegal to possess, 
sell, deliver, carry, transport, or ship any such wildlife that has 
been taken illegally. Certain exceptions apply to our agents and State 
conservation agencies.
    Permits may be issued to carry out otherwise prohibited activities 
involving endangered wildlife under certain circumstances. Regulations 
governing permits are codified at 50 CFR 17.22 and 17.23. Such permits 
are available for scientific purposes, to enhance the propagation or 
survival of the species, and for incidental take in connection with 
otherwise lawful activities.
    It is our policy, as published in the Federal Register on July 1, 
1994 (59 FR 34272), to identify to the maximum extent practicable at 
the time a species is listed those activities that would or would not 
constitute a violation of section 9 of the Act. The intent of this 
policy is to increase public awareness of the effect of the listing on 
proposed and ongoing activities within a species' range. We believe 
that, based on the best available information, the following actions 
are not likely to result in a violation of section 9, provided these 
actions are carried out in accordance with any existing regulations and 
permit requirements:
    (1) Possession, delivery, including interstate transport and import 
or export from the United States, involving no commercial activity, of 
Sonoma County California tiger salamanders that were collected prior to 
the date of publication of the emergency listing rule in the Federal 
    (2) Any actions that may affect the Sonoma County California tiger 
salamander that are authorized, funded, or carried out by a Federal 
agency, when the action is conducted in accordance with the 
consultation requirements for listed species pursuant to section 7 of 
the Act;
    (3) Any action taken for scientific research carried out under a 
recovery permit issued by us pursuant to section 10(a)(1)(A) of the 
    (4) Land actions or management carried out under a habitat 
conservation plan approved by us pursuant to section 10(a)(1)(B) of the 
Act, or an approved conservation agreement; and
    (5) Grazing management practices that do not result in the 
degradation or elimination of suitable California tiger salamander 
    Activities that we believe could potentially result in a violation 
of section 9 of the Act include, but are not limited to:
    (1) Unauthorized possession, collecting, trapping, capturing, 
killing, harassing, sale, delivery, or movement, including intrastate, 
interstate, and foreign commerce, or harming, or attempting any of 
these actions, of Sonoma County California tiger salamanders. Research 
activities where

[[Page 13519]]

salamanders are trapped or captured will require a permit under section 
10(a)(1)(A) of the Act;
    (2) Activities authorized, funded, or carried out by Federal 
agencies that may affect the Sonoma County California tiger salamander, 
or its habitat, when such activities are not conducted in accordance 
with the consultation for listed species under section 7 of the Act;
    (3) Discharges or dumping of toxic chemicals, silt, or other 
pollutants into, or other alteration of the quality of waters 
supporting Sonoma County California tiger salamanders that results in 
death or injury of the species or that results in degradation of their 
occupied habitat;
    (4) Release of exotic species (including, but not limited to, 
bullfrogs, tiger salamanders, mosquito fish, bass, sunfish, bullhead, 
catfish, crayfish) into Sonoma County California tiger salamander 
breeding habitat;
    (5) Destruction or alteration of uplands associated with seasonal 
pools used by Sonoma County California tiger salamanders during 
estivation and dispersal, or modification of migration routes such that 
migration and dispersal are reduced or precluded; and
    (6) Activities (e.g., habitat conversion, excessive livestock 
grazing, road and trail construction, recreation, development, and 
unauthorized application of herbicides and pesticides in violation of 
label restrictions) that directly or indirectly result in the death or 
injury of larvae, sub-adult, or adult Sonoma County California tiger 
salamanders, or modify Sonoma County California tiger salamander 
habitat in such a way that it adversely affects their essential 
behavioral patterns including breeding, foraging, sheltering, or other 
life functions. Otherwise lawful activities that incidentally take 
Sonoma County California tiger salamanders, but have no Federal nexus, 
will require a permit under section 10(a)(1)(B) of the Act.
    Questions regarding whether specific activities will constitute a 
violation of section 9 should be directed to the Field Supervisor of 
the Sacramento Fish and Wildlife Office (see FOR FURTHER INFORMATION 
CONTACT section). Requests for copies of the regulations regarding 
listed species and inquiries regarding prohibitions and permits may be 
addressed to the U.S. Fish and Wildlife Service, Endangered Species 
Permits, 911 NE 11th Avenue, Portland, OR 97232-4181 (503/231-2063; 
facsimile 503/231-6243).

Effective Date

    We published the emergency rule listing the Sonoma County DPS of 
the California tiger salamander as endangered on July 22, 2002 (67 FR 
47726). The emergency rule set forth a 240-day period temporarily 
adding this species to the List of Threatened and Endangered Wildlife, 
and that period expires on March 19, 2003. This final rule must be 
published on or before this date to prevent Federal protection for the 
Sonoma County California tiger salamander from expiring. In addition, 
as part of the June 6, 2002, settlement with the CBD, we are required 
to make a final determination on this listing action on or before March 
19, 2003. Because of these reasons, we find that good cause exists for 
this rule to take effect immediately upon publication in accordance 
with 5 U.S.C. 553(d)(3).

National Environmental Policy Act

    We have determined that an Environmental Assessment and 
Environmental Impact Statement, as defined under the authority of the 
National Environmental Policy Act of 1969, need not be prepared in 
connection with regulations adopted pursuant to section 4(a) of the 
Endangered Species Act as amended. We published a notice outlining our 
reasons for this determination in the Federal Register on October 25, 
1983 (48 FR 49244).

Paperwork Reduction Act

    This rule does not contain any new collections of information other 
than those already approved by the Office of Management and Budget 
under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq., and assigned 
control number 1018-0094, which is valid through July 31, 2004. This 
rule will not impose record keeping or reporting requirements on State 
or local governments, individuals, businesses, or organizations. An 
agency may not conduct or sponsor, and a person is not required to 
respond to, a collection of information, unless it displays a currently 
valid control number.

Executive Order 13211

    On May 18, 2001, the President issued an Executive Order 13211 on 
regulations that significantly affect energy supply, distribution, and 
use. Executive Order 13211 requires agencies to prepare Statements of 
Energy Effects when undertaking certain actions. This rule is not 
expected to significantly affect energy supplies, distribution, or use. 
Therefore, this action is not a significant energy action and no 
Statement of Energy Effects is required.

References Cited

    A complete list of all references cited in this rulemaking is 
available upon request from the Sacramento Fish and Wildlife Office 
(see ADDRESSES section).


    The primary author of this rule is David E. Wooten, U.S. Fish and 
Wildlife Service, Sacramento Fish and Wildlife Office (see ADDRESSES 

List of Subjects in 50 CFR Part 17

    Endangered and threatened species, Exports, Imports, Reporting and 
recordkeeping requirements, Transportation.

Regulation Promulgation

    For the reasons given in the preamble, we amend part 17, subchapter 
B of chapter I, title 50 of the Code of Federal Regulations, as set 
forth below:


    1. The authority citation for part 17 continues to read as follows:

    Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C. 
4201-4245; Pub. L. 99-625, 100 Stat. 3500, unless otherwise noted.

    2. Amend Sec.  17.11(h) by revising the entry for ``California 
tiger salamander'' under AMPHIBIANS, in the List of Endangered and 
Threatened Wildlife, to read as follows:

Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

                     Species                                              Vertebrate
--------------------------------------------------                     population where                                     Critical
                                                     Historic range     endangered or       Status       When listed        habitat       Special rules
          Common name            Scientific name                          threatened

                                                                      * * * * * * *
Salamander, California tiger..  Ambystoma          U.S.A. (CA)......  U.S.A. (CA--Santa  E             677E, 702......  NA.............  NA.
                                 californiense.                        Barbara County).

[[Page 13520]]

 Do...........................  ......do.........  ......do.........  U.S.A. (CA--       ......do      729E, 734......  ......do.......   do.
                                                                       Sonoma County).

                                                                      * * * * * * *

    Dated: March 12, 2003.
Marshall P. Jones, Jr.,
Director, Fish and Wildlife Service.
[FR Doc. 03-6454 Filed 3-18-03; 8:45 am]