[Federal Register: April 12, 2000 (Volume 65, Number 71)]
[Rules and Regulations]               
[Page 19686-19698]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]



Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AF34

Endangered and Threatened Wildlife and Plants; Threatened Status 
for the Santa Ana Sucker

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.


SUMMARY: We, the Fish and Wildlife Service (Service), determine 
threatened status according to the Endangered Species Act of 1973, as 
amended (Act), for the Santa Ana sucker (Catostomus santaanae). The 
species is threatened by potential habitat destruction, natural and 
human-induced changes in streamflows, urban development and related 
land-use practices, intensive recreation, introduction of nonnative 
competitors and predators, and demographics associated with small 
populations. The final rule invokes the Federal protection afforded by 
the Act for the Santa Ana sucker within the Los Angeles, San Gabriel, 
and Santa Ana River drainages.

DATES: The effective date of this rule is May 12, 2000.

ADDRESSES: The complete file for this rule is available for inspection, 
by appointment, during normal business hours at the U.S. Fish and 
Wildlife Service, Carlsbad Fish and Wildlife Office, 2730 Loker Avenue 
West, Carlsbad, California 92008.

FOR FURTHER INFORMATION CONTACT: Glen W. Knowles, Fish and Wildlife 
Biologist, U.S. Fish and Wildlife Service, Carlsbad Fish and Wildlife 
Office (telephone 760-431-9440; facsimile 760-431-9624).



    The Santa Ana sucker (Catostomus santaanae) is a recognized species 
and member of the sucker family (Catostomidae) (Robbins et al. 1991). 
The Santa Ana sucker was originally described as Pantosteus santa-anae 
by Snyder (1908). The genus Pantosteus was reduced to a subgenus of 
Catostomus, and the hyphen was omitted from the specific name in a 
subsequent revision of the nomenclature (Smith 1966). Smith and Koehn 
(1971) and Smith (1992) continued to recognize Pantosteus as a 
subgenus, although several authors have followed earlier usage (Miller 
1959) in recognizing Pantosteus as a genus related to Catostomus 
(Minckley 1973; Minckley et al. 1986).
    Moyle (1976a) described the Santa Ana sucker as being less than 16 
centimeters (cm) (6.3 inches (in.)) in length. The species is silvery 
below and darker along the back, with irregular blotches and pigmented 
membranes connecting the rays of the tail (Moyle 1976a).
    The Santa Ana sucker inhabits streams that are generally small and 
shallow, with currents ranging from swift (in canyons) to sluggish (in 
the bottomlands). All the streams are subject to periodic severe 
flooding (Moyle 1976a). Santa Ana suckers appear to be most abundant 
where the water is cool (less than 22 deg. Celsius (72 deg. 
Fahrenheit)), unpolluted, and clear, although they can tolerate and 
survive in seasonally turbid water (Moyle 1976a; Moyle and Yoshiyama 
1992). Santa Ana suckers feed mostly on algae, diatoms, and detritus 
scraped from rocks and other hard substrates, with aquatic insects 
making up a very small component of their diet. Larger fish generally 
feed more on insects than do smaller fish (Greenfield et al. 1970; 
Moyle 1976a).
    Santa Ana suckers generally reach sexual maturity in just over 1 
year and typically do not live more than 3 years (Greenfield et al. 
1970). Spawning generally occurs from early April to early July, with a 
peak in spawning activity occurring in late May and June (Greenfield et 
al. 1970; Moyle 1976a). The spawning period may be variable and 
protracted, however. Recent field surveys on the East Fork of the San 
Gabriel River found evidence of an extended spawning period. These 
surveys found small juveniles (30 millimeters (mm) standard length (1.2 
in.)) in December (1998) and March (1999) at the San Gabriel River site 
(U.S. Geological Survey (USGS) data, in litt. 1999). This data 
indicates that spawning may be very protracted in this stream, and 
begin as early as November. The fecundity of the Santa Ana sucker 
appears to be exceptionally high for a small sucker species (Moyle 
1976a). Total fecundity of six females, ranging in size from 78 mm (3.1 
in.) to 158 mm (6.2 in.), ranged from 4,423 to 16,151 eggs (Greenfield 
et al. 1970). The combination of early sexual maturity, a protracted 
spawning period, and high fecundity should allow the Santa Ana sucker 
to quickly repopulate streams following periodic flood events that 
could decimate populations (Moyle 1976a).
    Historically, the Santa Ana sucker appeared to be native to the 
rivers and larger streams of the Los Angeles Basin--the Los Angeles, 
San Gabriel, and Santa Ana River drainage systems in Los Angeles, 
Orange, Riverside, and San Bernardino Counties (Smith 1966). Although 
historic records are scarce, Santa Ana suckers presumably ranged from 
near the Pacific Ocean to the uplands of the Los Angeles and San 
Gabriel River systems, and to at least where Pump House #1 is now 
located (near the San Bernardino National Forest boundary) in the Santa 
Ana River (Swift et al. 1993; Camm Swift, Icthyologist Consultant, 
pers. comm. 1996). Although the Santa Ana sucker was described as 
common in the 1970s (Moyle 1976a), the species has experienced declines 
throughout most of its range (Moyle et al. 1995; Swift et al. 1993). 
The species is now restricted to three noncontiguous populations:

[[Page 19687]]

lower Big Tujunga Creek (Los Angeles River drainage); the East, West, 
and North Forks of the San Gabriel River (San Gabriel River drainage); 
and the lower and middle Santa Ana River (Santa Ana River drainage) 
(Moyle et al. 1995; Swift et al. 1993). A population also occurs in 
portions of the Santa Clara River drainage system in Ventura and Los 
Angeles Counties. The Santa Clara population is presumed to be an 
introduced population, although this presumption is based on the 
absence of the species from early collections, and not on any 
documented records of introduction (Hubbs et al. 1943; Miller 1968; 
Moyle 1976a; Bell 1978). The Santa Clara River population was not 
included in the proposal to list the Santa Ana sucker as threatened 
because of its presumed introduced status (see the proposed rule, 64 FR 
3915, for further details on this population). In this document, we 
define the native range of the Santa Ana sucker, as outlined in the 
proposed rule, to include populations in the Los Angeles River, San 
Gabriel River, and Santa Ana River drainage systems.

Los Angeles River System

    Although historically present, the species may now be extirpated 
from the Los Angeles River (Swift et al. 1993). Santa Ana suckers are 
still found in portions of Big Tujunga Creek (a tributary of the Los 
Angeles River) between Big Tujunga Dam and Hansen Dam. Surveys 
downstream of the Big Tujunga Dam found the species to be present but 
rare (fewer than 20 individuals collected at each site) just below the 
dam, as well as in the vicinities of Delta Flat and Wildwood. The 
species was found to be abundant (an estimated 200 individuals 
collected) near Stoneyvale (Mike Wickman, Angeles National Forest, in 
litt. 1996). Several thousand Santa Ana suckers were observed in a 
visual survey of Big Tujunga Creek in small sections from the 
confluence of Little Tujunga Creek to the Foothill Boulevard bridge in 
May 1999 (C. Swift, pers. com. 1999). Santa Ana suckers were also 
common in visual surveys of Big Tujunga Creek from Foothill Boulevard 
to the intersection of Oro Vista and Mt. Gleason Avenues in May 1999 
(Glen Knowles, U.S. Fish and Wildlife Service, in litt. 1999a); 
however, by October 1999, this reach had dried up entirely. Santa Ana 
suckers were abundant in October 1999 in the approximately 1-mile-long 
stretch of flowing waters of Big Tujunga and Haines Canyon Creeks 
between the 210 Freeway and Hansen Dam, as were two other rare native 
fish species, arroyo chub (Gila orcutti) and Santa Ana speckled dace 
(Rhinichthys osculus ssp.). Santa Ana suckers could not be found in 
other parts of the Big Tujunga Creek in October 1999, which were dry 
except for a few isolated shallow pools (G. Knowles, in litt. 1999a). 
In late summer and autumn of dry years, Big Tujunga Creek becomes a dry 
wash for much of its length. During these times, Santa Ana suckers may 
be restricted to about 1 mile of stream in the Los Angeles River Basin. 
We estimate that the Santa Ana sucker has lost approximately 80 percent 
of its historic native range in the Los Angeles River Basin. The 
portions of Big Tujunga Creek currently occupied by the Santa Ana 
sucker constitute approximately 25 percent of the total remaining 
native range of the species. Approximately 60 percent of the current 
range of the Santa Ana sucker in the Los Angeles River Basin occurs on 
private lands. The remaining 40 percent of the range in the Los Angeles 
River Basin occurs on Angeles National Forest lands managed by the U.S. 
Forest Service (USFS).

San Gabriel River System

    Santa Ana suckers were common in the San Gabriel River below Morris 
Dam, near Fish Canyon, until the mid-1970s (C. Swift, in litt. 1999a). 
However, no suckers were found in surveys conducted below Morris Dam in 
1995 (Dr. Tom Haglund, University of California, Los Angeles, in litt. 
1996). Santa Ana suckers were also absent from 1998 surveys in the 
mainstem San Gabriel River at Browns Gulch, below Morris Dam, and at 
Rainbow Ranch (Chambers Group 1999). Santa Ana suckers were present in 
1998 Chamber Group surveys of the West Fork of the San Gabriel River 
(Chambers Group 1999); however, surveys conducted by California 
Department of Fish and Game (CDFG) in 1998 and 1999 failed to locate 
suckers in the West Fork (Ray Ally, CDFG, in litt. 1999; Robert C. 
Hight, CDFG, in litt. 1999). However, CDFG did find Santa Ana suckers 
in Bear Creek, a tributary of the West Fork San Gabriel River, in June 
1999 (R. Ally, CDFG, in litt. 1999). Quarterly surveys indicated 
suckers were common in the East Fork of the San Gabriel River 
throughout 1999 (Mike Saiki, USGS Biological Resources Division (BRD), 
pers. comm. 1999). Thus, the Santa Ana sucker now appears extant only 
upstream of the confluence of the East, West, and North Forks of the 
San Gabriel River. Furthermore, the population of Santa Ana suckers in 
the North Fork is small, and the population in the West Fork appears to 
be declining. The portions of the San Gabriel River occupied by the 
Santa Ana sucker constitute approximately 15 percent of the total 
remaining native range of the species. However, data gathered during 
sampling indicates that the San Gabriel River may contain the most 
individuals of any remaining population (R. Ally, in litt. 1996; Mike 
Guisti, CDFG, in litt. 1996; M. Wickman, in litt, 1996; Juan Hernandez, 
CDFG, in litt. 1997; M. Saiki, pers. com. 1999). We estimate that the 
Santa Ana sucker has lost approximately 75 percent of its native range 
in the San Gabriel River. Approximately 15 percent of the current range 
of the Santa Ana sucker in the San Gabriel River Basin occurs on 
private lands. The remaining 85 percent of the range in the San Gabriel 
River Basin occurs in the Angeles National Forest. Even with the 
substantial decrease in the sucker's range in the San Gabriel River 
drainage system, Moyle and Yoshiyama (1992) considered this population 
of Santa Ana suckers to be the only viable population within the 
species' native range.

Santa Ana River System

    In 1986 and 1987, several hundred Santa Ana suckers were observed 
in the Santa Ana River downstream of Prado Dam (C. Swift, pers. comm. 
1996). By 1996, a general fish survey below Prado Dam yielded only 5 
suckers from a total of 271 fishes captured (M. Guisti, CDFG, in litt. 
1996). In April 1987, only five suckers were found during a sampling 
effort above the Prado Dam from the City of Norco to about 5 kilometers 
(km) (3.1 miles (mi)) upstream. In addition to fish being scarce above 
the dam, no small individuals were observed, indicating the possibility 
of little or no reproduction occurring in the area (Moyle and Yoshiyama 
1992). In 1991, sampling indicated that, although fishery habitat in 
the Santa Ana River was primarily fair to poor, Santa Ana suckers were 
abundant between Norco and Riverside (Chadwick and Associates 1992). 
Additionally, evidence suggested Santa Ana suckers were using 
tributaries, including Tequesquite Arroyo, Sunnyslope Channel, and Anza 
Park Drain, for spawning and nurseries (Chadwick and Associates 1996). 
Seventy-six Santa Ana suckers were taken in three collections about 2.0 
km (1.2 mi) below Hamner Avenue, Anaheim County, in the summer of 1997. 
An extensive survey of the Santa Ana River between Weir Canyon Road and 
Hamner Avenue, in Anaheim County, during the summer of 1998 yielded 42 
Santa Ana suckers. All were juveniles less than 70 mm (2.8 in.) long 
(C. Swift, in litt, 1998). However, recently, in surveys between 

[[Page 19688]]

and November 1999, seven adult suckers were captured near River Road, 
Riverside--three in the main-stem Santa Ana River, and four in the 
diversion channel that diverts most of the river's flow into the Prado 
Wetlands (C. Swift, in litt. 1999). Snorkel surveys of the Santa Ana 
River between Mission Boulevard and Riverside Avenue in Riverside in 
November 1999 found several pockets of tens to hundreds of Santa Ana 
suckers, usually in the deepest areas of the stream (C. Swift, pers. 
comm. 1999). Although Chadwick and Associates (1991) collected one 
Santa Ana sucker in this area near Mission Boulevard in March 1991, 
they stated that this reach probably would not support viable 
populations of fishes due to elevated levels of ``chlorine and 
unionized ammonia'' in this reach and unsuitable breeding substrates. 
Recent surveys in September and December 1999 in the Metropolitan Water 
District crossing near the Van Buren Avenue bridge in Riverside 
captured 48 and 16 suckers, respectively, although these individuals 
appeared to be in poorer body condition than those in the San Gabriel 
River (Barbara Martin, USGS, BRD, pers. comm. 1999). Extensive surveys 
of the Santa Ana River at Imperial Highway in December 1998 and March, 
June, September, and December 1999 failed to record any Santa Ana 
suckers (B. Martin, pers. comm. 1999).
    Chadwick and Associates (1996) noted that length-frequency analysis 
indicates Santa Ana suckers are naturally reproducing in the Santa Ana 
River system. However, they asserted that Santa Ana sucker population 
decreases, as evidenced by 1996 surveys, were due to high flows in the 
basin between 1991 and 1996 (M. Guisti, in litt., 1996). T. Haglund (in 
litt. 1996) contended that a large number of suckers reported in 
tributaries are juveniles and may be the progeny of very few adults. 
The presence of juveniles in surveys at the Metropolitan Water District 
Crossing, in March, June, and September 1999, represent positive 
evidence of recruitment, despite the apparent lack of suitable spawning 
habitat at that site (M. Saiki, pers. comm. 1999).
    Santa Ana suckers occur in the lower portions of the Santa Ana 
River, with current survey records from the vicinity of Weir Canyon 
Road in Anaheim to Riverside Avenue in Riverside, but are now 
apparently absent from the upper reach of the river in the San 
Bernardino Mountains (Moyle and Yoshiyama 1992; Swift et al. 1993). We 
estimate that the Santa Ana sucker has lost approximately 70 percent of 
its native range in the Santa Ana River. The portions of the Santa Ana 
River occupied by the Santa Ana sucker constitute approximately 60 
percent of the total remaining native range of the species. 
Approximately 75 percent of the range of the species in the Santa Ana 
River Basin occurs on private lands. The balance is within State, 
county, city, and regional park lands, with a small portion, 3 percent, 
on military lands.
    In summary, the Santa Ana sucker has declined throughout 
significant portions of its range. The species has lost approximately 
75 percent of its native range. Recent population densities range from 
approximately 246 fish in 2.9 km (1.8 mi) on the East Fork of the San 
Gabriel River (J. Hernandez, in litt. 1997) to 16 fish in 1.6 km (1.0 
mile) of the Santa Ana River in December 1999 (USGS Survey Data, in 
litt. 1999). This overall reduction in range, and the more localized 
reductions in numbers, are particularly surprising given the high 
fecundity and apparent broad habitat tolerances of the species. 
Urbanization, water diversions, dams, introduced competitors and/or 
predators, and other human-caused disturbances likely are playing a 
role in the decline of the species. These factors have also been 
implicated in the decline of other western suckers (Minckley et al. 
1991; Scoppettone and Vinyard 1991).
    The decline of the Santa Ana sucker is also part of a greater 
overall decline of freshwater fishes in Southern California. The Los 
Angeles Basin was or is home to at least seven native species of 
freshwater fishes that have been declining or have been extirpated 
since the 1930s (Swift et al. 1993). Four of these species, the 
steelhead (Oncorhynchus mykiss), the Pacific lamprey (Lampetra 
tridentata), the Pacific brook lamprey (Lampetra cf. pacifica), and the 
unarmored three-spined stickleback (Gasterosteus aculeatus 
williamsoni), have been extirpated from the Los Angeles Basin since the 
1950s. Two others, the Santa Ana speckled dace (Rhinichthys osculus), 
and the arroyo chub (Gila orcutti), have become rare in the Los Angeles 
Basin (Swift et al. 1993).

Previous Federal Action

    On September 6, 1994, we received a petition under the Act (16 
U.S.C. 1531 et seq.) to list the Santa Ana sucker (Catostomus 
santaanae), Santa Ana speckled dace (Rhinichthys osculus), and Shay 
Creek threespine stickleback (Gasterosteus aculeatus) as endangered 
species. The petition was submitted by the Sierra Club Legal Defense 
Fund, Inc., on behalf of seven groups including the California-Nevada 
Chapter of the American Fisheries Society, The Nature School, 
California Sportfishing Protection Alliance, Friends of the River, 
Izaak Walton League of America, California Trout, and Trout Unlimited. 
We deferred processing this petition because of other higher priority 
listing actions and severe funding constraints imposed by a number of 
continuing resolutions between November 1995 and April 1996.
    On July 9, 1996, we published a 90-day petition finding (61 FR 
36021) that substantial information had been presented indicating 
listing may be warranted for the Santa Ana sucker. On November 26, 
1996, we published a notice initiating a status review for the Santa 
Ana sucker (61 FR 60073). On April 3, 1997, we published a 12-month 
finding (62 FR 15872) that listing the Santa Ana sucker was warranted, 
but precluded by higher listing priorities. On January 26, 1999, we 
proposed threatened status for the Santa Ana sucker within its native 
historic range of the Los Angeles, San Gabriel and Santa Ana River 
Systems (64 FR 3915). After the close of the comment period, we 
received seven requests to reopen the comment period. These requests 
asked us to consider new information gained from ongoing studies on the 
species, and to consider the use of a special rule under section 4(d) 
of the Act to implement a long-term conservation program for the 
species in the Santa Ana River. On December 16, 1999, we reopened the 
comment period to satisfy the public notice requirements of the Act and 
our regulations (50 CFR 424.16(c)(vi)), and to consider new scientific 
information (64 FR 70209).
    The processing of this final rule conforms with our Final Listing 
Priority Guidance published in the Federal Register on October 22, 1999 
(64 FR 57114). The guidance clarifies the order in which we will 
process rulemakings. Highest priority is processing emergency listing 
rules for any species determined to face a significant and imminent 
risk to its well-being (Priority 1). Second priority (Priority 2) is 
processing final determinations on proposed additions to the lists of 
endangered and threatened wildlife and plants. Third priority (Priority 
3) is processing new proposals to add species to the lists. The 
processing of administrative petition findings (petitions filed under 
section 4 of the Act) is the fourth priority (Priority 4). The 
processing of this final rule is a Priority 2 action.

[[Page 19689]]

Summary of Comments and Recommendations

    In the January 26, 1999, proposed rule (64 FR 3915), we requested 
interested parties to submit factual reports or information that might 
contribute to development of a final rule. The 60-day comment period 
closed on March 29, 1999. We contacted appropriate Federal and State 
agencies, county and city governments, scientific organizations, and 
other interested parties. We reopened the comment period on December 
16, 1999, to satisfy the public notice requirements of the Act and to 
consider new scientific information. The reopened comment period closed 
on January 3, 2000. We published public notices of the proposed rule in 
the Los Angeles Times, the Orange County Register, and the Riverside 
Press Enterprise on December 17, 1999, which invited general public 
comment. We did not receive any requests for a public hearing.
    During the public comment periods, we received written comments 
from 45 individuals, organizations, and State and local agencies. Of 
the comments received, 32 were in support of listing, 3 were opposed, 
and 10 were neutral. Some commenters submitted updated status 
information on the Santa Ana sucker and new information on possible 
threats to the species. This information has been incorporated in the 
``Background'' and ``Summary of Factors Affecting the Species'' 
sections. We address all other comments received during the comment 
periods in the following summary of issues. Comments of a similar 
nature are grouped into a single issue.
    Issue 1: Several commenters felt that the Santa Ana sucker should 
be listed as an endangered species, rather than a threatened species.
    Our Response: Most of these comments did not provide additional 
information or criteria to justify listing the species as endangered. 
Those commenters who did provide a basis for endangered status 
identified potential habitat destruction, natural and human-induced 
changes in streamflows, urban development and related land-use 
practices, intensive recreation, the introduction of nonnative 
competitors and predators, and demographics associated with small 
populations as reasons that remaining populations were threatened with 
extinction. We agree that multiple factors threaten the Santa Ana 
sucker (see ``Summary of Factors Affecting the Species'' section). 
However, we do not believe the Santa Ana sucker meets the Act's 
definition of endangered, which is a species ``in danger of extinction 
throughout all or a significant portion of its range.'' The Act defines 
a threatened species as ``any species which is likely to become an 
endangered species within the foreseeable future throughout all or a 
significant portion of its range'' (section 3(19)). Although current 
population estimates do not exist for any of the sucker populations, 
all of the currently known populations within the native range were 
surveyed in 1999. In each drainage, suckers were locally common in 
1999, and no populations appeared to be in imminent danger of 
extinction. We conclude that the remaining populations that constitute 
the native range of Santa Ana sucker are likely to become in danger of 
extinction in the foreseeable future. Therefore, the Act's definition 
of a threatened species fits the current situation of the Santa Ana 
sucker best.
    Issue 2: Some commenters expressed support for designating critical 
habitat and felt that we should designate critical habitat for the 
species at the time of listing. Other commenters offered specific 
recommendations for areas to list as critical habitat, or requested 
that we not designate critical habitat in specific stream reaches.
    Our Response: In this rule, as in the proposed rule, we find that 
critical habitat is not determinable because the biological needs of 
the Santa Ana sucker are not sufficiently known to identify an area as 
critical habitat. When a ``not determinable'' finding is made, we must, 
within 2 years of the publication date of the original proposed rule, 
propose the designation of critical habitat unless such designation is 
found to be not prudent. For a more detailed evaluation of our critical 
habitat finding for the Santa Ana sucker, and an explanation of ``not 
determinable'' and ``not prudent'' findings, please see the ``Critical 
Habitat'' section.
    Issue 3: Some commenters requested that we list the Santa Clara 
population as threatened or endangered. Another commenter asked if the 
Santa Clara River population would require any increased protection 
because of its possible role in the recovery of the species.
    Our Response: In the proposed rule, we identified only those Santa 
Ana sucker populations within the native range of the species for 
listing as threatened. The native range of the Santa Ana sucker is 
considered to be the rivers and streams of the Los Angeles, San 
Gabriel, and Santa Ana River Basins. The Santa Clara population is 
presumed to be an introduced population, although this presumption is 
based on its absence from early collections, and not on a documented 
record of introduction (Hubbs et al. 1943; Miller 1968; Moyle 1976a; 
Bell 1978). Therefore, the Santa Clara River population was not 
included in the proposal to list the species.
    We believe that the Santa Ana sucker has lost about 75 percent of 
its historic native range. Considering the total remaining range of the 
species as all those areas currently occupied by the Santa Ana sucker, 
including both native and introduced populations, the portions of the 
Santa Clara River occupied by the species constitute approximately 50 
percent of the total remaining range of the species. In light of the 
current status of the Santa Ana sucker, and the portion of the 
remaining range that occurs in the Santa Clara River system, further 
evaluation of the Santa Clara population is needed to determine its 
role in the recovery of the species. If the Santa Clara River 
population is determined to be crucial to the recovery of the species, 
we may need to reevaluate the status of this population under the Act.
    Issue 4: Several commenters expressed the opinion that recreational 
suction dredging actually benefits the Santa Ana sucker, and that such 
suction dredging should be allowed to continue in streams occupied by 
the species.
    Our Response: Suction dredging is the use of a suction system to 
remove and return material at the bottom of a stream, river, or lake 
for the extraction of minerals. Suction dredging in California is 
regulated by the CDFG under section 228 of the California Code of 
Regulations and by the U.S. Army Corps of Engineers (USACE) under 
section 404 of the Clean Water Act. The USFS may also regulate this 
activity by closing streams to dredging on Forest Service lands. The 
USACE does not require a section 404 permit for holders of a CDFG 5653 
Standard Dredge Permit, but does require a 404 permit for all other 
types of dredging. Suction dredge operators are required to obtain a 
permit from CDFG, which is valid for a calender year (J. Reese, USACE, 
in litt. 1995; CDFG, in litt. 1999). In 1999, all counties where the 
Santa Ana sucker naturally occur were open to suction dredging (Los 
Angeles, Orange, and Riverside Counties); however, the East Fork of the 
San Gabriel River and portions of the West Fork of the San Gabriel 
River are covered by special regulation. The East Fork is the only 
stream containing Santa Ana suckers that is commonly subject to suction 
dredging. CDFG issues special dredge permits for this stream with 
conditions to exclude dredging from April 1 to June 30. The closed 
period is to allow

[[Page 19690]]

resident fish and amphibians to spawn without interference from 
dredging. CDFG issued approximately 200 special dredging permits in 
1995 for the East Fork, the first year the stream had been dredged 
legally in 15 years. This number has decreased steadily to 
approximately 40 special dredging permits issued in 1999 (Dwayne 
Maxwell, CDFG, pers. comm. 1999).
    Few studies exist on suction dredging and its effects on aquatic 
ecosystems. Of the studies conducted, most indicate that the effects of 
a single suction dredge on overall habitat and on benthic (bottom of 
the stream) aquatic insect communities are highly localized and short 
term, but vary with stream gradient, flow regime, and sediment load 
characteristics of the stream (Griffith and Andrews 1981; Harvey et al. 
1982; Thomas 1985; Harvey 1986; Hall 1988; Somer and Hassler 1992). In 
general, suction dredging removes all substrates smaller than the 
diameter of the intake nozzle and deposits them as large, unstable 
piles just downstream from the dredge. Harvey et al. (1982) found that 
on the American River, Yuba River, and Butte Creek, California, 
settleable solids and sedimentation rate both increased within several 
meters of the suction dredge, but rapidly returned to ambient levels 
downstream. Turbidity, however, was more variable. Streams with higher 
clay content substrates experienced greater long-lasting changes in 
turbidity. As with the work by Harvey et al. (1982), Thomas (1985) 
found during a study on Gold Creek in Missoula County, Montana, that 
suction dredging had only localized, short-term effects on insects 
living in the soil. Just after dredging, numbers of soil-living insects 
were significantly reduced in the dredged area. However, within 10 
meters (32.5 feet) downstream of the dredged area, insect numbers and 
turbidity were normal. Within a month, aquatic insect numbers had 
returned to normal in the dredged section of the stream (Thomas 1985). 
In addition, Somer and Hassler (1992) found that, while the species 
composition of benthic insects was altered within sections of streams 
adjacent to suction dredging, overall abundance remained the same.
    Thomas (1985) observed cutthroat trout opportunistically feeding on 
invertebrates dislodged by a suction dredge. In some circumstances, 
habitat may be temporarily created by suction dredging. Harvey (1986) 
observed that fish occupying a riffle during late summer in Butte 
Creek, California, moved into a newly created dredge excavation, 
presumably seeking deeper water. Harvey found that adult fishes in 
general were not sensitive to dredging; however, riffle sculpin (Cottus 
gulosus), a benthic species, was displaced from suction-dredged areas, 
probably due to disturbance of its microhabitat. Harvey also suspected 
that the microhabitats of speckled dace (Rhinichthys osculus) would 
also be deleteriously altered by suction dredging.
    Although the effects of recreational suction dredging on adult 
fishes may range from beneficial to deleterious, such dredging appears 
to have strong negative impacts to early life stages of fishes. 
Griffith and Andrews (1981) found a mortality rates of up to 100 
percent for cutthroat trout (Oncorhynchus clarki) eggs and fry, and 
rainbow trout (O. mykiss) un-eyed eggs and sac fry that pass through a 
suction dredge. Harvey and Lisle (1998) noted that passing through a 
suction dredge would likely kill eggs, larvae, and fry of other types 
of fishes as well, including suckers (Catostomidae). Harvey et al. 
(1995) concluded that small larvae of fish such as suckers are easily 
damaged by physical disturbance caused by the dredge, but adults and 
juveniles are unlikely to be directly affected by suction dredges since 
they can either avoid or survive the passage through a dredge. In a 
review of the current literature on suction dredging, Harvey and Lisle 
(1998) concluded that while effects from dredging may be minor and 
local in some situations, fisheries managers would be prudent to 
consider dredging to be a harmful practice in streams that support 
threatened or endangered species.
    No studies exist that specifically address the effects of suction 
dredging on Santa Ana suckers. In the proposed rule, we concluded that 
suction dredging may impact larvae and eggs of Santa Ana suckers, 
particularly if dredging is concentrated in an area containing spawning 
suckers. Santa Ana suckers and speckled dace, another species in the 
East Fork of the San Gabriel River, appear to prefer larger 
unconsolidated cobble substrates. These types of substrates may 
actually be created by suction dredging (Harvey and Lisle 1998). Also, 
suction dredging may provide local increases in food resources for fish 
(Thomas 1985). However, as stated above, suction dredging could result 
in mortality of eggs or larvae during spawning periods, and so should 
be excluded from Santa Ana sucker habitats during spawning. We will 
continue to evaluate the overall effects of suction dredging on Santa 
Ana suckers and provide specific recommendations to CDFG and the USFS 
based on those results.
    Issue 5: We received comments that the Service should consider the 
application of a special rule under section 4(d) of the Act for the 
Santa Ana sucker in the Santa Ana River. The special rule would exempt 
certain activities from the take prohibitions of the Act, so long as a 
Service-approved Santa Ana sucker conservation plan is funded and 
implemented. The conservation plan would provide for the conservation 
of the species within the Santa Ana River watershed.
    Our Response: Under section 4(d) of the Act, we have the authority 
to issue regulations as deemed necessary and advisable to provide for 
the conservation of a species listed as threatened. We are interested 
in pursuing collaborative, proactive efforts to conserve the Santa Ana 
sucker. A special rule under section 4(d) could provide an incentive 
for State, county, and local jurisdictions, as well as private land 
owners, to protect and conserve the Santa Ana sucker. This special rule 
could potentially provide for substantial conservation of the Santa Ana 
sucker. The comments we received from the County of Orange, Orange 
County Water District, and Santa Ana River Watershed Group provided 
background information to consider the possibilities of a special rule 
under section 4(d). If our review of this information indicates that 
the application of a special rule under 4(d) to facilitate the 
conservation of the Santa Ana sucker warrants further evaluation, we 
will publish in the Federal Register a notice of intent to consider 
such a rule.
    Issue 6: Commenters expressed concerns about the effects of listing 
the Santa Ana sucker on the continued use of the San Gabriel Canyon Off 
Highway Vehicle Area (SGCOHVA), located at the confluence of the East 
and West Forks of the San Gabriel River in the Angeles National Forest.
    Our Response: Although surveys in 1999 failed to record the Santa 
Ana sucker in the West Fork of the San Gabriel River (R. Ally, CDGF, in 
litt. 1999), the species was found within 1.6 km (1.0 mile) of the 
SGCOHVA during 1999 surveys of the East Fork (G. Knowles, in litt. 
1999b). Therefore, we conclude that Santa Ana suckers can be expected 
to occur in the SGCOHVA.
    The commenters stated that the use of the SGCOHVA would have 
minimal impact to the species because off-road vehicles are not used in 
streams but cross streams only to access other areas of the SGCOHVA. 
However, the operation of off-road vehicles in the SGCOHVA could 
adversely affect Santa Ana sucker habitat due to increased

[[Page 19691]]

sedimentation to the stream from erosion, or alteration of channel 
morphology from the physical disturbance of crossing the stream. In 
addition, one recent study found that certain types of stream crossings 
can act as barriers to fish movement (Warren and Pardew 1998), although 
temporary ford crossings, such as those currently in the SGCOHVA, were 
not a significant barrier to fish dispersal. Since the overall impact 
of the SGCOHVA to Santa Ana suckers is not currently known, further 
evaluation is required. Under section 7 of the Act, Federal agencies 
are required to insure, through consultation with us, that any actions 
they authorize, fund, or carry out are not likely to jeopardize the 
continued existence of any listed species. The USFS would need to 
consult with us on the impacts that off-road vehicles in the SGCOHVA, 
or other ongoing and future activities on national forest lands, would 
have on Santa Ana suckers.
    Issue 7: Several commenters were concerned that future efforts to 
repatriate the Santa Ana sucker into streams of the upper Santa Ana 
River Drainage would adversely impact the operation of hydroelectric 
facilities in the area.
    Our Response: No decision has been made to reestablish Santa Ana 
suckers into areas formerly occupied by the species. However, 
considering the large amount of habitat loss (the Santa Ana sucker is 
believed to be extirpated from about 75 percent of its former range), 
reintroduction of Santa Ana suckers into formerly occupied habitats may 
be an important component of a recovery plan for the species. A 
decision to reintroduce the Santa Ana suckers to formerly occupied 
areas would be part of the recovery efforts for the species and would 
include analysis under and compliance with the Act, National 
Environmental Policy Act (NEPA), and other applicable Federal laws and 
regulations. Such analysis would include an evaluation of the impacts 
reintroduction would have on hydroelectric facilities and ways to 
minimize potential conflicts.
    Issue 8: Commenters were concerned that listing the Santa Ana 
sucker would impair the ability of flood control districts to protect 
upland property from flooding. A commenter stated that the Santa Ana 
sucker has managed to adapt to the long history of flood control and 
maintenance activities in the Santa Ana River, and therefore, these 
activities should be allowed to continue. According to the commenters, 
flood control districts are willing to work with us to develop plans 
that would promote the recovery of the Santa Ana sucker to the 
``maximum extent possible.''
    Our Response: The issue of flood control in Santa Ana sucker 
habitat is of critical importance. We disagree that the species has 
managed to adapt to flood control activity in the Santa Ana River. 
Flood control activity, such as bank stabilization, channelization, 
vegetation removal, drop structures, and the construction of dams, 
dikes, and diversions, has been implicated as a key factor responsible 
for the decline of not only the Santa Ana sucker but six other species 
of freshwater fishes native to the Los Angeles Basin (Swift et al. 
1993). An example of the adverse impacts of flood control activity on 
this species is the Santa Ana River at Imperial Highway (State Highway 
90) near Anaheim. Santa Ana suckers were common at this site in the 
late 1980s and early 1990s. During the last 15 years, the USACE has 
undertaken various flood control activities at the site. The river has 
been channelized, riparian vegetation removed, and banks stabilized 
with rip rap and concrete. Santa Ana suckers have not been recorded in 
this reach since 1996. Although the exact reasons for the apparent 
disappearance of Santa Ana suckers from this area may never be known, 
the drastic changes to its habitat by flood control activities are 
plausibly a key factor (Chadwick and Associates 1996; Robert Fisher, 
pers. comm. 1999; M. Saiki, pers. comm. 1999).
    We commend the willingness of the flood control districts to work 
with us to develop a plan to recover the Santa Ana sucker. The Santa 
Ana River, within the jurisdiction of various flood control districts, 
contains some of the best remaining occupied habitat for Santa Ana 
suckers within this drainage, and the protection and enhancement of 
this habitat likely will be crucial to the recovery of the species. 
Certain flood control activities are regulated by the USACE under 
section 404 of the Clean Water Act. Under section 7 of the Act, Federal 
agencies are required to insure, through consultation with us, that any 
actions they authorize, fund, or carry out are not likely to jeopardize 
the continued existence of any listed species. The impacts of ongoing 
and future flood control activities to Santa Ana sucker would be 
addressed during the section 7 consultation process. In addition, we 
are considering proposing special regulations under the authority of 
section 4(d) of the Act that would promote the conservation of the 
Santa Ana sucker by exempting certain activities from the take 
prohibitions of the Act in association with implementing locally 
prepared, Service-approved programs that would contribute to the 
overall conservation of the species (see ``Issue 5'').
    Issue 9: Commenters expressed the concern that the listing of the 
Santa Ana sucker is premature because sound scientific evidence does 
not exist demonstrating that the species populations are decreasing, 
because surveys have been inadequate to document declining populations, 
and because apparent declines represent natural variation in population 
size resulting from climate cycles and not from human-induced changes 
to ecosystems.
    Our Response: We estimate that the Santa Ana sucker has been 
eliminated from about 75 percent of its former native range. This loss 
has been caused by habitat destruction, natural and human-induced 
changes in streamflows, urban development and related land-use 
practices, and the introduction of nonnative competitors and predators 
(Moyle et al. 1995; Swift et al. 1993). The utilization of the rivers 
of the Los Angeles Basin for irrigation began as early as 1821, and was 
extensive by the 1880s (Miller 1961). The demands of an increasing 
human population in the Los Angeles area resulted in an extreme level 
of utilization of the Los Angeles Basin Rivers that was apparent as 
early as 1930, when McGlashan (1930) wrote of the Santa Ana River, 
``Probably no other stream of its size in the United States is made to 
serve greater or more varied uses.'' By the 1950s, urbanization of the 
greater Los Angeles metropolitan area had resulted in severe declines 
of the native fish fauna of the Los Angeles Basin, such that four fish 
species had been extirpated from the basin (Swift et al. 1993). This 
urbanization resulted in conversion of Santa Ana sucker habitat to the 
concrete-lined storm drains that now constitute the lowermost reaches 
of the Los Angeles, San Gabriel, and Santa Ana Rivers (Mount 1995) (see 
``Summary of Factors Affecting the Species'' section). Moyle and 
Yoshiyama (1992) stated, ``[e]ven though Santa Ana suckers seem to be 
quite generalized in their habitat requirements, they are intolerant of 
polluted or highly modified streams.'' The impacts associated with 
urbanization are likely the primary cause of the extirpation of Santa 
Ana suckers from lower reaches of the Los Angeles, San Gabriel, and 
Santa Ana Rivers. We, therefore, disagree with the contention that 
sound scientific evidence does not exist demonstrating that the species 
is decreasing. The decline of the Santa Ana sucker and the destruction 
of its habitat are well documented (Miller 1961; Moyle 1976a;

[[Page 19692]]

Moyle and Yoshiyama 1992; Swift et al. 1993; Moyle et al. 1995).
    Issue 10: Commenters expressed the belief that the newly completed 
Seven Oaks Dam, upstream from the present range of Santa Ana sucker in 
the Santa Ana River, would not act as a barrier to upstream fish 
movement. The only flows connecting the upper and lower Santa Ana River 
Basins in the last 40 years have been extreme flood flows, which would 
cause Santa Ana suckers to be lost downstream. In fact, commenters felt 
that Seven Oaks Dam would be beneficial for the species by reducing the 
amount of fine particles and sand deposited downstream in flood flows, 
sediments that threaten Santa Ana sucker habitat in the Santa Ana 
    Our Response: We agree that the surface flows of the Santa Ana 
River between Riverside and Seven Oaks Dam have long been diverted to 
provide water for the communities in southwestern San Bernardino County 
and western Riverside County. We also agree that this dewatered 
stretch, and not the dam, is the current primary barrier to the 
movement of Santa Ana suckers upstream in the Santa Ana River. However, 
records from the 1940s indicate that Santa Ana suckers were once a 
common resident in the now dewatered stretch of the Santa Ana River 
near San Bernardino. The restoration of a more perennial flow to these 
areas may make these areas suitable for Santa Ana suckers. Ideally, 
connectivity between the upper and lower portions of the drainage would 
allow for gene flow throughout the population. However, even if water 
was returned to dry reaches of the Santa Ana River, Seven Oaks Dam 
would prevent movement of Santa Ana suckers between formerly occupied 
upstream habitats and the lower reaches they occupy now. Thus, Seven 
Oaks Dam represents a more permanent barrier to the movement of fishes 
than dewatered sections of the stream.
    We agree that sediment load characteristics of the Santa Ana River 
have been modified downstream from Seven Oaks Dam. However, the 
ultimate effects on sediment characteristics of the Santa Ana River 
downstream of the newly completed Seven Oaks Dam are, at best, 
difficult to predict. In general, streams below newly closed dams are 
changed through narrowing and deepening of their channels and 
coarsening of their beds. This generally results in an armored 
condition of the river bed just below the dam, such that the bed is 
lined with relatively large particles that were mobile during high 
flood flows before the dam was closed but are now too heavy to be moved 
by the new regime (Graf 1988; Mount 1995). Also, most dams have a high 
trap efficiency, meaning that they trap most sediment. Only the finer 
sediments get through (Mount 1995). So, although we cannot know for 
certain what effect the newly completed Seven Oaks Dam will have on the 
Santa Ana River downstream, we can generally predict that it will 
result in a decrease of coarser materials and an increase in finer 
substrates delivered to downstream reaches. Seven Oaks Dam will further 
prevent the Santa Ana River from functioning as a natural river, a 
scenario that has often had numerous negative impacts on the aquatic 
environment (Hunt 1988; Harden 1996; McCully 1996), as well as on the 
resident fish populations (Miller 1961; Moyle 1976a; Minckley and 
Deacon 1991; Mount 1995).

Peer Review

    In accordance with the interagency peer review policy published on 
July 1, 1994 (59 FR 34270), we solicited the expert opinions of 
independent specialists regarding pertinent scientific or commercial 
data and assumptions relating to the taxonomy, population status, and 
supportive biological and ecological information for the taxon under 
consideration for listing. 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. 
We requested four individuals, who possess expertise in Santa Ana 
sucker biology and Catostomid ecology, and whose affiliations include 
academia, a Federal agency, and a private company, to review the 
proposed rule by the close of the comment period. Two individuals 
responded to our request, and we have addressed their comments in the 
previous section of the rule, and in updating the ``Background'' and 
``Summary of Factors Affecting the Species'' sections.

Summary of Factors Affecting the Species

    Section 4 of the Act and regulations (50 CFR part 424) issued to 
implement the listing provisions of the Act set forth the procedures 
for adding species to the Federal Lists. A species may be determined to 
be an endangered or threatened species due to one or more factors 
described in section 4(a)(1) of the Act. These factors and their 
application to the Santa Ana sucker (Catostomus santaanae) are as 

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

    Moyle and Yoshiyama (1992) concluded that the native range of the 
Santa Ana sucker is largely coincident with the Los Angeles 
metropolitan area. Intensive urban development of the area has resulted 
in water diversions, extreme alteration of stream channels, changes in 
the watershed that result in erosion and debris torrents, pollution, 
and the establishment of introduced nonnative fishes. Moyle and 
Yoshiyama (1992) stated, ``[e]ven though Santa Ana suckers seem to be 
quite generalized in their habitat requirements, they are intolerant of 
polluted or highly modified streams.'' The impacts associated with 
urbanization are likely the primary cause of the extirpation of this 
species from lowland reaches of the Los Angeles, San Gabriel, and Santa 
Ana Rivers.
    As the Los Angeles urban area expanded, the Los Angeles Basin 
rivers (the Los Angeles, Santa Ana, and San Gabriel Rivers) were highly 
modified, channelized, or moved in an effort to either capture water 
runoff or protect property. As Moyle (1976a) stated, ``[t]he lower Los 
Angeles River is now little more than a concrete storm drain.'' The 
same is true for the Santa Ana and San Gabriel Rivers. These 
channelized rivers and canals with uniform and altered substrates do 
not appear to be suitable for sustaining Santa Ana sucker populations 
(Swift et al. 1993; Chadwick and Associates 1996), and the species 
appears to persist only in reaches that remain relatively 
unchannelized. Past and continuing projects have resulted (or will 
result) in channelization of the Santa Ana River throughout most of the 
range of the Santa Ana sucker in Orange County. Urban development also 
threatens the Santa Ana sucker in the Los Angeles and Santa Ana River 
Basins. This urban development has also resulted in changes in water 
quality and quantity and the hydrologic regime of these rivers. The 
Santa Ana sucker is one of seven native freshwater fish species of the 
Los Angeles Basin that have declined drastically in the last 70 years. 
Four of these species, the steelhead, Pacific lamprey, Pacific brook 
lamprey, and the unarmored threespine stickleback have been extirpated 
from the Los Angeles Basin since the 1950s, and two others are very 
rare (Santa Ana speckled dace and arroyo chub), presumably due to the 
same factors that have caused the decline of the Santa Ana sucker 
(Swift et al. 1993) (For an example of the apparent effects of

[[Page 19693]]

channelization on Santa Ana suckers, see ``Issue 8'' in the ``Summary 
of Comments and Recommendations'' section).
    All three river systems have dams that isolate and fragment fish 
populations. These dams have likely resulted in some populations being 
excluded from suitable spawning and rearing tributaries. Reservoirs 
created by the dams also provide areas where introduced predators and 
competitors can live and reproduce (Moyle and Light 1996) (see factor C 
of this section). The newly completed Seven Oaks Dam, upstream from the 
present range of Santa Ana sucker in the Santa Ana River, forms a 
barrier for the upstream movement of fish and further isolates Santa 
Ana sucker populations from their native range in the headwaters of the 
    The population of Santa Ana suckers in the West Fork of the San 
Gabriel River is threatened by accidental high flows from Cogswell 
Reservoir, which have devastated this section of stream several times 
in the past (Moyle and Yoshiyama 1992; Haglund and Baskins 1992; T. 
Haglund, in litt. 1996). T. Haglund (in litt. 1996) stated that, 
``[t]he West Fork population was wiped out by a sluicing event (removal 
of sediment by releasing a sudden flow of water) from Cogswell Dam in 
1981 (anecdotal data) but recolonized from tributaries that acted as 
refugia. However, data (from CDFG, no date) suggest that the suckers 
have never returned to their former abundance.'' Santa Ana suckers have 
biological adaptations that allow the fish to quickly repopulate 
streams following periodic flood events (Moyle et al. 1995). However, 
successive high flows could eliminate the sucker population in the West 
Fork of the San Gabriel River by rapidly depleting the individuals soon 
after they migrate into the mainstem from tributaries. Proposals for 
additional sluicing or other sediment removal activities from the 
Cogswell reservoir on the San Gabriel River system are being considered 
(R. C. Hight, in litt. 1999). The potential effects of the proposed 
sediment management project may also degrade the habitat of the Santa 
Ana sucker by depositing large amounts of silt on the streambed, 
causing a rapid increase in suspended sediments in the water column.
    The petitioners contended that suction dredge mining has increased 
in the Cattle Canyon tributary to the East Fork of the San Gabriel 
River, thereby threatening the Santa Ana sucker. A commenter indicated 
that no suction dredging has occurred in Cattle Canyon and suggested 
that the petitioners took Moyle and Yoshiyama (1992) out of context 
(Gerald Hobbs, Public Lands Action Committee, in litt. 1996, 1999). The 
CDFG (Patricia Wolf, CDFG, in litt. 1996) indicated they are not aware 
of suction dredging in the Cattle Canyon tributary to the East Fork of 
the San Gabriel River. However, they had issued nearly 200 Special 
Dredge Permits for the East Fork of the San Gabriel River in 1995, the 
first time the East Fork had been dredged in 15 years. This number has 
dropped to approximately 40 Special Dredge Permits issued in 1999 for 
the East Fork San Gabriel River (D. Maxwell, CDFG, pers. comm. 1999). 
Even though surveys from 1996 through 1999 indicate the East Fork of 
the San Gabriel River continues to maintain a healthy Santa Ana sucker 
population (R. Ally, in litt. 1996; J. Hernandez, in litt. 1997;, M. 
Saiki, pers. comm. 1999), suction dredging may impact larvae and eggs 
of Santa Ana suckers, particularly if dredging is concentrated in an 
area containing spawning suckers. Harvey and Lisle (1998) recommended 
that, given the uncertainty concerning the effects of suction dredging, 
fisheries managers would be wise to assume that suction dredging is a 
harmful practice in streams that support threatened or endangered 
species. (See ``Issue 4'' in the ``Summary of Comments and 
Recommendations'' section.)
    Recreational activities on forest lands may also pose some threat 
to Santa Ana sucker habitat quality. Annually, thousands of people from 
the Los Angeles metropolitan area and adjacent urban communities use 
wilderness and nonwilderness areas within the Big Tujunga Creek and San 
Gabriel Forks areas of the Angeles National Forest for recreation. The 
impact of large numbers of people using these areas include destruction 
of streambank vegetation, streambank erosion, and the disposal of 
untreated human waste and other refuse into the creeks, all of which 
degrade water quality (D. Maxwell, CDFG, pers. comm. 1999). Given the 
projected growth of the Los Angeles metropolitan area, this threat 
should increase.
    Although the Santa Ana sucker evolved under conditions that 
presumably included droughts, water diversions and management practices 
threaten the continued existence of the species. For example, stretches 
of the upper Santa Ana River have been permanently dewatered, 
eliminating Santa Ana sucker populations and migration through these 
reaches to other areas (Swift et al. 1993). As previously discussed, 
channelization of the rivers of the Los Angeles Basin, water quality 
degradation, and dam construction have all combined to degrade and 
eliminate historic Santa Ana sucker habitat. Future human population 
and urban growth of the basin will further stress the natural resources 
of the basin and likely exacerbate these conditions by further 
destruction and degradation of Santa Ana sucker habitat.
    Degradation of water quality in the Santa Ana and Los Angeles 
Rivers may threaten the Santa Ana sucker (Moyle and Yoshiyama 1992). 
Suckers are common in some areas upstream from Prado Dam where several 
water treatment facilities discharge into the Santa Ana River (Chadwick 
and Associates 1992). Chadwick and Associates (1992) attributed high 
sucker numbers to adequate water supplies discharged by the treatment 
facilities and the presence of tributaries that offer spawning areas 
and refugia for suckers. However, they did note that the Santa Ana 
River between Mission Boulevard and Interstate 10 probably would not 
support viable populations of fishes, due, in part, to ``elevated 
levels of chlorine and unionized ammonia.'' Overall, Santa Ana sucker 
numbers are much reduced in the Santa Ana River, and the Santa Ana 
River population appears to be less healthy than populations in other 
rivers occupied by the species (Moyle and Yoshiyama 1992; M. Saiki, 
pers. comm. 1999; P. Wolf, in litt. 1996).
    The small mile-long stretch of Big Tujunga and Haines Canyon Creeks 
that appears to provide a critical refugia for the Santa Ana sucker, as 
well as the arroyo chub and Santa Ana speckled dace, is threatened by 
the potential water quality impacts of a proposed golf course 
development to be built just upstream of Interstate 210 (Bill Eick, in 
litt. 1999). Cohen et al. (1999) reviewed studies of 36 golf courses 
around the United States in an effort to evaluate the impacts to water 
quality by golf courses. Although no toxicologically significant 
impacts were observed by the authors, maximum allowable concentrations 
of pesticides and related chemicals for aquatic organisms occasionally 
were exceeded. Moreover, maximum contaminant levels/health advisory 
levels were frequently exceeded for various pesticides and ground water 
nitrate-nitrogen. Although the water quality tolerances of Santa Ana 
suckers are unknown, in general, point and non-point source pollution 
(e.g., urban runoff, sedimentation) have significantly degraded the 
water quality in most of the native range of the Santa Ana sucker.
    In an effort to identify what environmental variables affect the 
Santa Ana sucker, the Biological Resources Division of the USGS, in 
conjunction with the Orange County Water District,

[[Page 19694]]

County of Orange, Los Angeles County Department of Public Works, and 
the Service, is nearing completion of a study of the factors affecting 
Santa Ana sucker abundance. Initial results from this study indicate 
that tissue concentrations of inorganic and organic contaminants from 
Santa Ana suckers from the San Gabriel and Santa Ana Rivers were not 
unusually high. However, measurements of electrical conductance and 
turbidity did show significant negative correlations with Santa Ana 
sucker abundance, indicating that Santa Ana suckers are less tolerant 
where conditions are more turbid and contain more salts (M. Saiki, 
pers. comm. 1999). Based on available information, we conclude that 
increased turbidity and associated deposition of fine particles and 
sand likely threaten the Santa Ana sucker population in the Santa Ana 
River by decreasing the availability of cobble and other hard 
substrates and altering the water quality preferred by the species 
(Moyle and Yoshiyama 1992).

B. Overutilization for Commercial, Sporting, Scientific, or Educational 

    We are not aware of any commercial or recreational demand for the 
Santa Ana sucker. Although the CDFG reported that Santa Ana suckers had 
been illegally caught with gill and throw nets in the Santa Ana River 
below Prado Dam (Lt. M. Maytorena, CDFG, pers. comm. 1997), the 
relative impact of illegal harvesting of the species is unknown.

C. Disease or Predation

    Moyle and Yoshiyama (1992) concluded that introduced brown trout 
(Salmo trutta) may have caused the extirpation of the Santa Ana sucker 
from the upper Santa Ana River in the San Bernardino Mountains. The 
petitioners noted that centrarchid (sunfishes) and bullheads prey on 
suckers. In the Los Angeles River, such introduced predators aggregate 
in pools during droughts and are presumably feeding on native fishes, 
including Santa Ana suckers (Sierra Club Legal Defense Fund, in litt. 
1994). Similar conditions exist in the Santa Ana River. Predation by 
introduced fishes in combination with habitat destruction has been 
implicated in the decline of other species of suckers in the Southwest 
(Minckley et al. 1991; Scoppettone and Vinyard 1991) and on native 
fishes in general in California (Moyle 1976b).
    Initial results from the USGS study mentioned above indicate that 
the presence of nonnative fish species was more strongly correlated 
with the absence of Santa Ana suckers than any water quality variable. 
Strongly significant negative associations were found with common carp 
(Cyprinus carpio), largemouth bass (Micropterus salmoides), bluegill 
(Lepomis macrochirus), and fathead minnow (Pimephales promelas), 
indicating nonnative fishes may exclude Santa Ana suckers by 
competition, or eliminate suckers through predation (M. Saiki, pers. 
comm. 1999). Nonnative introduced fishes have long been recognized as 
having far-reaching negative impacts to native fishes in North America 
(Moyle et al. 1986). Accordingly, introduced predators and competitors 
likely threaten the continued existence of Santa Ana suckers throughout 
most of the range of the species.

D. The Inadequacy of Existing Regulatory Mechanisms

    Despite existing regulatory mechanisms and conservation activities 
accomplished to date by private, State, and Federal entities, the Santa 
Ana sucker has continued to decline throughout a significant portion of 
its range. Existing regulatory mechanisms that might provide some 
protection for the Santa Ana sucker if it was not listed include the 
California Endangered Species Act, California Environmental Quality Act 
(CEQA), NEPA, Clean Water Act, Federal Endangered Species Act (where 
the Santa Ana sucker occurs in areas where other federally listed 
species are located), and land management or conservation measures by 
Federal, State, or local agencies or by private groups and 
    The State of California considers the Santa Ana sucker a ``species 
of special concern.'' However, the Santa Ana sucker is not listed as 
endangered or threatened by the State, and ``species of special 
concern'' are afforded no protection under the California Endangered 
Species Act.
    CEQA requires full public disclosure of the potential environmental 
impact of proposed projects. This law also obligates disclosure of 
environmental resources within proposed project areas and may enhance 
opportunities for conservation efforts. However, CEQA does not 
guarantee that such conservation efforts will be implemented. The 
public agency with primary authority or jurisdiction over the project 
is designated as the lead agency under CEQA, and is responsible for 
conducting a review of the project and consulting with other agencies 
concerned with resources affected by the project. Section 15065 of the 
CEQA guidelines 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.'' Although not currently listed under the 
California Endangered Species Act, the Santa Ana sucker would likely 
qualify as a rare species under section 15380 of the CEQA guidelines 
and thus would be given the same consideration under CEQA as those 
species that are officially listed with the State. Once significant 
impacts are identified, the lead agency may either require mitigation 
for effects through changes in the project or decide that overriding 
considerations justify approval of a project with significant impacts. 
In the latter case, projects may be approved that cause significant 
environmental damage, such as resulting in the loss of habitat 
supporting State-listed species. Protection of listed species through 
CEQA is, therefore, not assured.
    NEPA requires an intensive environmental review of projects that 
may adversely affect a federally listed species, but project proponents 
are not required to avoid impacts to nonlisted species. The primary 
purpose of NEPA is to require Federal agencies to fully disclose 
impacts that would result from their proposed actions, and to make 
findings regarding the significance of those impacts. It does not 
require that resources be protected.
    Lead agencies responsible under CEQA and/or NEPA have made 
determinations that have adversely affected, or would adversely affect, 
the Santa Ana sucker and its habitat. Examples of projects that have 
been completed or are currently undergoing the review process under 
CEQA and/or NEPA that would impact this species include the Santa Ana 
River Mainstem Project, containing multiple projects including Seven 
Oaks Dam and the raising of Prado Dam, and the continued channelization 
of the Santa Ana River in Orange County. The reviews for these projects 
have not addressed the effects of the proposed actions on the Santa Ana 
sucker, despite its status as a species proposed for listing. 
Similarly, on the San Gabriel River, proposed silt removal from 
Cogswell Dam may adversely affect the sucker. While projects altering a 
stream course are subject to review under section 1601 or 1603 of the 
California Fish and Game Code, such State regulations have not 
prevented habitat loss or sufficiently protected habitats to prevent 
the decline of the Santa Ana sucker.
    Section 404 of the Clean Water Act currently affords some 
protection for the Santa Ana sucker. However, the Clean Water Act, by 
itself, does not provide

[[Page 19695]]

adequate protection for the Santa Ana sucker. Although the objective of 
the Clean Water Act is to ``restore and maintain the chemical, 
physical, and biological integrity of the Nation's waters'' (33 U.S.C. 
1251), this law contains no specific provisions to address the 
conservation needs of rare species. USACE is the Federal agency with 
primary responsibility for administering the section 404 program. Under 
section 404, nationwide permits may be issued for certain activities 
that are considered to have minimal impacts, including minor dredging 
and discharges of dredged material, some road crossings, and minor bank 
stabilization (December 13, 1996; 61 FR 65873). USACE seldom withholds 
authorization of an activity under nationwide permits unless the 
existence of a listed threatened or endangered species would be 
jeopardized. Activities that do not qualify for authorization under a 
nationwide permit, including projects that would result in more than 
minimal adverse environmental effects, either individually or 
cumulatively, may be authorized by an individual permit or regional 
general permit, which are typically subject to more extensive review. 
Regardless of the type of permit deemed necessary under section 404, 
rare species such as the Santa Ana sucker may receive no special 
consideration with regard to conservation or protection unless they are 
listed under the Act.
    As part of the section 404 review process, we provide comments to 
USACE on nationwide permits and individual permits under the Fish and 
Wildlife Coordination Act. Our comments are only advisory, although 
procedures exist for elevating permit review within the agencies when 
disagreements between us and USACE arise concerning the issuance of a 
permit. In practice, the section 404 permit review process has often 
proven to be inadequate to protect unlisted but rare species, such as 
the Santa Ana sucker.
    The Santa Ana sucker may receive a small amount of protection from 
the overlap of its habitat with two federally endangered birds, the 
least Bell's vireo (Vireo bellii pusillus) and the southwestern willow 
flycatcher (Empidonax traillii extimus). Consideration for these listed 
bird species protects some areas from projects that could ultimately 
damage Santa Ana sucker habitat. However, protection is limited because 
these listed bird species occupy different areas and have dissimilar 
ecological requirements from the Santa Ana sucker. Although the 
federally endangered San Bernardino kangaroo rat (Dipodomys merriami 
parvus) also occurs along the Santa Ana River, this listed mammal 
occurs upstream from the present range of the Santa Ana sucker. 
Therefore, the presence of the San Bernardino kangaroo rat will have 
little effect on the status or protection afforded the sucker.
    USFS lands encompass approximately 15 percent of the current native 
range of the Santa Ana sucker. Although a small percentage of the range 
is within a designated wilderness area, the majority of the range on 
USFS lands is not under wilderness management. Wilderness designation 
offers no direct regulatory protection to the sucker, but it does 
reduce some human-induced impacts on the stream. For example, motorized 
equipment is excluded from these areas. This restriction reduces or 
eliminates all motorized recreation and mining activities within the 
wilderness areas. Because these types of activities may harm Santa Ana 
sucker populations and habitats, wilderness designation offers some 
indirect benefit to the species. Santa Ana sucker habitat on USFS is 
also not subject to the development pressures existing on private land. 
However, this protection likely is partially offset by the recreational 
impacts discussed earlier (see factor ``A'').

E. Other Natural or Manmade Factors Affecting its Continued Existence

    Periodic wildfires could adversely affect Santa Ana suckers by 
eliminating vegetation that shades the water and moderates water 
temperature, or by producing silt-and-ash-laden runoff that can 
significantly increase the turbidity of rivers. Although recent fires, 
including the 1996 Biedebach Fire (near the vicinity of Prairie Fork on 
the East Fork of the San Gabriel River) and the 1999 Bridge Fire 
(adjacent to the West and North Forks of the San Gabriel River), did 
not burn the riparian corridor, they may have contributed increased 
runoff and siltation to the creek.
    The high degree of fragmentation of the remaining Santa Ana sucker 
populations makes the species especially vulnerable to random events, 
environmental factors, and loss of genetic variability. A small 
population size increases the rate of inbreeding and may allow 
increased expression of deleterious recessive genes occurring in the 
population (known as inbreeding depression). Loss of genetic 
variability, through random genetic drift (random gene frequency 
changes in a small population due to chance), reduces the ability of 
small populations to respond successfully to environmental stresses. 
Most of the lowland river habitats have been lost, and the remaining 
populations of Santa Ana suckers are low in numbers, with the exception 
of the San Gabriel Forks populations. Although Santa Ana suckers are 
locally common in what remains of their native range, the total 
population size of any one of the remaining native populations is still 
relatively small. Random events, such as floods, variations of annual 
weather patterns, predation and associated demographic uncertainty 
(conditions affected by chance events, such as sex ratios, that 
influence survival and reproduction in small populations), or other 
environmental stresses and human-caused factors, such as chemical 
spills, may lead to the demise of the remnant populations in the Los 
Angeles or Santa Ana Basins.
    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
faced by this species in determining its status. Based on this 
evaluation, the preferred action is to list the Santa Ana sucker 
(Catostomus santaanae) as threatened. While not in immediate danger of 
extinction, the Santa Ana sucker is likely to become an endangered 
species in the foreseeable future if the present threats continue and 
populations decline further.

Critical Habitat

    Critical habitat is defined in section 3, paragraph (5)(A), of the 
Act as the specific areas within the geographic 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 essential to the 
conservation of the species and that may require special management 
considerations or protection; and specific areas outside the 
geographical area occupied by a species at the time it is listed in 
accordance with the provisions of section 4 of the Act, upon a 
determination 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.
    Critical habitat designation, by definition, directly affects only 
Federal agency actions through consultation under section 7(a)(2) of 
the Act. 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 a listed species or destroy or 
adversely modify its critical habitat.

[[Page 19696]]

    Section 4(a)(3) of the Act, as amended, and implementing 
regulations (50 CFR 424.12) require that, to the maximum extent prudent 
and determinable, the Secretary designate critical habitat at the time 
the species is determined to be endangered or threatened. According to 
Service regulations (50 CFR 424.12(a)), critical habitat is not 
determinable if information sufficient to perform required analysis of 
the impacts of the designation is lacking or if the biological needs of 
the species are not sufficiently well known to permit 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 he determines that the economic benefits of such exclusion 
outweigh the conservation benefits of designation, unless to do so 
would result in the extinction of the species.
    In designating critical habitat, we consider the following 
requirements of the species: Space for individual and population growth 
and for normal behavior; food, water, air, light, minerals, or other 
nutritional or physiological requirements; cover or shelter; sites for 
breeding, reproduction, or rearing of offspring; and, generally, 
habitats that are protected from disturbance or are representative of 
the historic geographical and ecological distributions of this species 
(see 50 CFR 424.12(b)). In addition to these factors, we also focus on 
the known physical and biological features (primary constituent 
elements) within the designated area that are essential to the 
conservation of the species and may require special management 
considerations or protection. The essential features for the Santa Ana 
sucker may include, but are not limited to, spawning sites, food 
resources, and water quality and quantity (see 50 CFR 424.12(b)).
    We conclude that the knowledge and understanding of the biological 
needs and environmental limitations of the Santa Ana sucker and the 
primary constituent elements of its habitat are insufficient to 
determine critical habitat for the fish. We believe that the Santa Ana 
sucker is intolerant of highly polluted waters, but little information 
is available concerning this possible limiting factor. Furthermore, in 
the Santa Ana River, suckers remain extant, although rare, in the lower 
reaches where water quality is degraded relative to the headwaters. We 
need additional information on the environmental limits of the sucker 
to enable us to accurately designate critical habitat for the Santa Ana 
sucker throughout its range. The physical and biological features 
including but not limited to water chemistry, water temperature, 
instream flows, streambed substrate and structure, and fauna and flora 
of the aquatic environment that supports the Santa Ana sucker are the 
features about which we need additional information. In an effort to 
gain these data, the Orange County Water District, the County of 
Orange, Los Angeles County Department of Public Works, the National 
Fish and Wildlife Foundation, the Biological Resources Division of 
USGS, and the Service have funded and implemented research on the 
environmental limitations of the Santa Ana Sucker. The study is nearing 
completion and has already identified some environmental parameters, 
including water quality (e.g., turbidity and conductivity) and some 
biological parameters (introduced nonnative fish species) associated 
with variations in population densities. These correlations will help 
guide future research to focus on the variable(s) most likely to limit 
sucker populations.
    When a ``not determinable'' finding is made, we must, within 2 
years of the publication date of the original proposed rule, propose 
the designation of critical habitat, unless the designation is found to 
be not prudent. Initial results of the USGS-Santa Ana sucker study have 
been incorporated into this rule. A final report should be available 
later this year. We will use this study and other new information to 
reevaluate our knowledge of the species and, if determined prudent, 
propose critical habitat for the Santa Ana sucker. We will continue in 
our efforts to obtain more information on Santa Ana sucker biology and 
ecology, including distribution, population density, and essential 
habitat characteristics, particularly in regard to water quality. We 
will also use the information resulting from these efforts to identify 
measures needed to achieve conservation of the species, as defined 
under the Act.

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened under the Endangered Species Act include recognition, 
recovery actions, requirements for Federal protection, and prohibitions 
against certain practices. Recognition through listing encourages and 
results in conservation actions by Federal, State, and private 
agencies, groups, and individuals. The Act provides for possible land 
acquisition and cooperation with the States, and requires that recovery 
plans be carried out for all listed species. Funding may be available 
through section 6 of the Act for the State to conduct recovery 
activities. The protection required of Federal agencies and the 
prohibitions against certain activities involving listed plants are 
discussed, 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 or 
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. Section 7(a)(4) requires Federal agencies to confer with us 
on any action that is likely to jeopardize the continued existence of a 
species proposed for listing or result in destruction or adverse 
modification of proposed critical habitat. If a species is listed 
subsequently, section 7(a)(2) of the Act requires Federal agencies to 
ensure that activities they authorize, fund, or carry out are not 
likely to jeopardize the continued existence of a listed species or 
destroy or adversely modify its critical habitat, if designated. If a 
Federal action may affect a listed species or its critical habitat, the 
responsible Federal agency must enter into formal consultation with us, 
under section 7(a)(2) of the Act.
    Federal agencies expected to consult with us under section 7 
regarding the Santa Ana sucker include USACE and the Environmental 
Protection Agency because of their permitting authority under section 
404 of the Clean Water Act. The USFS may consult with us on its 
activities on the Angeles National Forest and Los Padres National 
Forest. These agencies either administer lands/waters containing the 
Santa Ana sucker or authorize, fund, or otherwise conduct activities 
that may affect this species.
    The Act and its implementing regulations set forth a series of 
general prohibitions and exceptions that apply to all endangered and 
threatened wildlife not covered by a special rule. These prohibitions, 
codified at 50 CFR 17.21 and 17.31, in part, make it illegal for any 
person subject to the jurisdiction of the United States to take 
(including harass, harm, pursue, hunt, shoot, wound, kill, trap, 
capture, collect, or attempt any such conduct), import or 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 is also illegal to possess, sell, deliver, 
carry, transport, or

[[Page 19697]]

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 threatened wildlife under certain circumstances. Regulations 
governing permits are at 50 CFR 17.32. Such permits are available for 
scientific purposes, to enhance the propagation or survival of the 
species, and/or for incidental take in connection with otherwise lawful 
activities. For threatened species, permits also are available for 
zoological exhibition, educational purposes, or special uses consistent 
with the mission of the Act.
    As published in the Federal Register (59 FR 34272) on July 1, 1994, 
our policy is to identify to the maximum extent practicable those 
activities that would or would not be likely to constitute a violation 
of section 9 of the Act if a species is listed. The intent of this 
policy is to increase public awareness of the effect of a listing on 
proposed and ongoing activities within a species' range. We believe the 
following actions would not likely result in a violation of section 9:
    (1) Actions that may affect the Santa Ana sucker and are 
authorized, funded, or carried out by a Federal agency when the action 
is conducted in accordance with any reasonable and prudent alternatives 
or reasonable and prudent measures to minimize the impacts of take 
identified by us in accordance with section 7 of the Act; and
    (2) Possession, transport within or between States, and import and 
export, with proper permits, of Santa Ana suckers that were legally 
collected prior to the date of publication in the Federal Register of 
the final regulation adding this species to the list of threatened and 
endangered species.
    Activities that we believe could potentially harm the Santa Ana 
sucker and result in a violation of section 9 of the Act include, but 
are not limited to:
    (1) Take of Santa Ana suckers without a permit, which includes 
harassing, harming, pursuing, hunting, shooting, wounding, killing, 
trapping, capturing, or collecting, or attempting any of these actions;
    (2) Possessing, selling, delivering, carrying, transporting, or 
shipping illegally taken Santa Ana suckers;
    (3) Unauthorized interstate and foreign commerce (commerce across 
State and international boundaries) and import/export;
    (4) Introduction of nonnative species that compete or hybridize 
with, or prey on Santa Ana suckers;
    (5) Unauthorized destruction or alteration of Santa Ana sucker 
habitat by dredging, channelization, diversion, dewatering through 
groundwater withdraw, in-stream vehicle operation or rock removal, or 
other activities that result in the destruction or significant 
degradation of cover, channel stability, substrate composition, water 
quality, water temperature, and migratory corridors; and
    (6) Discharging or dumping of toxic chemicals, silt, organic waste, 
or other pollutants (such as may result from mining, land development 
or land management activities) into waters supporting Santa Ana suckers 
that results in death or injury to the species or results in the 
destruction or degradation of cover, channel stability, substrate 
composition, water quality, water temperature, and migratory corridors 
used by the species for foraging, cover, migration, and spawning.
    We will review other activities not identified above on a case-by-
case basis to determine if a violation of section 9 of the Act may be 
likely to result from such activity. We do not consider these lists to 
be exhaustive and provide them as information to the public.
    Questions regarding whether specific activities may constitute a 
violation of section 9 should be directed to the Field Supervisor of 
the Service's Carlsbad Fish and Wildlife Office (see ADDRESSES 
section). Requests for copies of the regulations regarding listed 
wildlife and inquiries about prohibitions and permits may be addressed 
to the U.S. Fish and Wildlife Service, Ecological Services, Endangered 
Species Permits, 911 N.E. 11th Avenue, Portland, Oregon 97232-4181 
(telephone 503/231-6241; facsimile 503/231-6243)

National Environmental Policy Act

    We have determined that environmental assessments and environmental 
impact statements, 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 of 1973, 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 under the Paperwork Reduction Act, 44 
U.S.C. 3501 et seq., and assigned Office of Management and Budget 
clearance number 1018-0094. 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. For additional 
information concerning permit and associated requirements for 
threatened wildlife, see 50 CFR 17.32.

References Cited

    A complete list of all references cited herein is available upon 
request from the Carlsbad Fish and Wildlife Office (see ADDRESSES 


    The primary author of this document is Glen W. Knowles, Carlsbad 
Fish and Wildlife Office, U.S. Fish and Wildlife Service (see ADDRESSES 

List of Subjects in 50 CFR Part 17

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

Regulation Promulgation

    Accordingly, we amend part 17, subchapter B of chapter I, title 50 
of the Code of Federal Regulations, as follows:


    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 adding the following, in alphabetical 
order under FISHES, to the List of Endangered and Threatened Wildlife:

Sec. 17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

[[Page 19698]]

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

                   *                  *                  *                  *                  *                  *                  *
Sucker, Santa Ana...............  Catostomus           U.S.A. (CA)........  Los Angeles River    T                       694           NA           NA
                                   santaanae.                                basin, San Gabriel
                                                                             River basin, Santa
                                                                             Ana River basin.
                   *                  *                  *                  *                  *                  *                  *

    Dated: March 31, 2000.
Jamie Rappaport Clark,
Director, Fish and Wildlife Service.
[FR Doc. 00-8999 Filed 4-11-00; 8:45 am]