[Federal Register: February 8, 1999 (Volume 64, Number 25)]

[Rules and Regulations]               

[Page 5963-5981]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]




Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AC26


Endangered and Threatened Wildlife and Plants; Determination of 

Threatened Status for the Sacramento Splittail

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.


SUMMARY: We, the U.S. Fish and Wildlife Service (Service), determine 

threatened status for the Sacramento splittail (Pogonichthys 

macrolepidotus) pursuant to the Endangered Species Act of 1973, as 

amended (Act). Sacramento splittail occur in Suisun Bay and the San 

Francisco Bay-Sacramento-San Joaquin River Estuary (Estuary) in 

California. The Sacramento splittail has declined by 62 percent over 

the last 15 years. This species is primarily threatened by changes in 

water flows and water quality resulting from the export of water from 

the Sacramento and San Joaquin rivers, periodic prolonged drought, loss 

of shallow-water habitat, introduced aquatic species, and agricultural 

and industrial pollutants. Designation of critical habitat is not 

prudent at this time. This rule implements the protection and recovery 

provisions afforded by the Act for Sacramento splittail.

EFFECTIVE DATE: March 10, 1999.

ADDRESSES: The complete file for this rule is available for public 

inspection, by appointment, during normal business hours at the 

Sacramento Fish and Wildlife Office, U.S. Fish and Wildlife Service, 

3310 El Camino Avenue, Suite 130, Sacramento, CA 95821-6340.

FOR FURTHER INFORMATION CONTACT: Michael Thabault, Deputy Assistant 

Field Supervisor, U.S. Fish and Wildlife Service (see ADDRESSES 

section) (telephone 916-979-2710).



    As used in this rule, the term ``Delta'' refers to all tidal waters 

contained within the legal definition of the San Francisco Bay-

Sacramento-San Joaquin River Delta, as delineated by section 12220 of 

the State of California's Water Code. Generally, the Delta is contained 

within a triangular area that extends south from the City of Sacramento 

to the confluence of the Stanislaus and San Joaquin rivers at the 

southeast corner and Chipps Island in Suisun Bay. The term ``Estuary,'' 

as used in this rule, refers to tidal waters contained in the 

Sacramento and San Joaquin rivers, the Delta, and San Pablo and San 

Francisco bays. ``Export facilities,'' as used in this rule, refer to 

the Central Valley Project and State Water Project water export 

facilities in the South Delta.

    Sacramento splittail were first described in 1854 by W.O. Ayres as 

Leuciscus macrolepidotus and by S.F. Baird and C. Girard as 

Pogonichthys inaeqilobus. Although Ayres' species description is 

accepted, the species was assigned to the genus Pogonichthys in 

recognition of the distinctive characteristics exhibited by the two 

California splittail species P. ciscoides and P. macrolepidotus 

(Hopkirk 1973). Pogonichthys ciscoides, endemic to Clear Lake, Lake 

County, California, has been extinct since the early 1970s. The 

Sacramento splittail (hereafter splittail) represents the only existing 

species in its genus in California.

    The name splittail refers to the distinctive tail of the fish. 

Pogon-ichthys means bearded fish, referring to the small barbels 

(whisker-like sensory organs) on the mouth of the fish, unusual in 

North American cyprinids. Macro-lepidotus means large-scaled. The 

splittail is a large cyprinid fish that can exceed 40 centimeters (cm) 

(16 inches (in)) in length (Moyle 1976). Adults are characterized by an 

elongated body, distinct nuchal hump (on the back of the neck), and 

small, blunt head, usually with barbels at the corners of the slightly 

subterminal mouth. The enlarged dorsal lobe of the caudal fin 

distinguishes the splittail from other minnows in the Central Valley of 

California. Splittail are dull, silvery-gold on the sides and olive-

gray dorsally. During spawning season, pectoral, pelvic, and caudal 

(tail) fins are tinged with an orange-red color. Males develop small 

white nuptial tubercles on the head. Breeding tubercles (nodules) also 

appear on the base of the fins (Moyle in prep).

    Splittail are native to California's Central Valley, where they 

were once widely distributed (Moyle 1976). Historically, splittail were 

found as far north as Redding on the Sacramento River (at the Battle 

Creek Fish Hatchery in Shasta County), as far south as the present-day 

site of Friant Dam on the San Joaquin River, and up the tributaries of 

the Sacramento River as far as the current Oroville Dam site on the 

Feather River and Folsom Dam site on the American River (Rutter 1908). 

Recreational anglers in Sacramento reported catches of 50 or more 

splittail per day prior to the damming of these rivers (Caywood 1974). 

Splittail were captured in the past in southern San Francisco Bay and 

at the mouth of Coyote Creek in Santa Clara County, but they are no 

longer present there (Moyle in prep). The species was part of the 

Central Valley Native American diet (Caywood 1974).

    In recent times, dams and diversions have increasingly prevented 

splittail from upstream access to the large rivers, and the species is 

now restricted to a small portion of its former range (Moyle and 

Yoshiyama 1992). However, during wet years, they migrate up the 

Sacramento River as far as the Red Bluff diversion dam in Tehama 

County, and into the lowermost reaches of the Feather and American 

rivers (Moyle in prep, Jones and Stokes 1993, Charles Hanson, State 

Water Contractors, in litt. 1993). Small numbers of splittail have 

recently been found in the upper Sacramento and San Joaquin rivers and 

their tributaries (Baxter 1995). Recent surveys of San Joaquin Valley 

streams found splittail in the San Joaquin River below its confluence 

with the Merced River, mainly following wet winters (Moyle in prep). 

Splittail have also been recorded using the Sutter and Yolo bypasses 

for spawning areas during wet winters (Sommer et al. 1997). Successful 

spawning has been recorded in the lower Tuolumne River during wet years 

in the 1980s, as well as in 1995. Both adults and juveniles were 

observed at Modesto, 11 kilometers (km) (6.6 miles (mi)) upriver from 

the mouth of the river (Moyle in prep). However, all of the sightings 

reported above were during wet years when splittail were able to 

exploit more spawning habitat. Except for very wet years, the species 

is for the most part now confined to the Delta, Suisun Bay, Suisun 

Marsh, and Napa Marsh. In the Delta, they are most abundant in the 

north and west portions when populations are low, but are more evenly 

distributed throughout the Delta following years of successful 

reproduction (Sommer et al. 1997).

    Splittail are relatively long-lived, frequently reaching 5 to 7 

years of age. An analysis of hard parts of the splittail indicate that 

larger fish may be 8 to 10

[[Page 5964]]

years old (Moyle in prep). Females are highly fecund, with the largest 

females producing over 250,000 eggs (Daniels and Moyle 1983). 

Populations fluctuate annually depending on spawning success, which is 

highly correlated with freshwater outflow and the availability of 

shallow-water habitat with submerged vegetation (Daniels and Moyle 

1983). Fish usually reach sexual maturity by the end of their second 

year. The onset of spawning is associated with rising water levels, 

increasing water temperatures, and increasing day length. Peak spawning 

occurs from the months of March through May, although records of 

spawning exist for late January to early July (Wang 1986). In some 

years, most spawning may take place within a limited period of time. 

For instance, in 1995, a year of extraordinarily successful spawning, 

most splittail spawned over a short period in April, even though larval 

splittail were captured from February through early July (Moyle in 

prep). Within each spawning season older fish reproduce first, followed 

by younger individuals (Caywood 1974). Spawning occurs over flooded 

vegetation in tidal freshwater and euryhaline habitats of estuarine 

marshes and sloughs and slow-moving reaches of large rivers. Larvae 

remain in shallow, weedy areas close to spawning sites for 10 to 14 

days and move into deeper water as they mature and swimming ability 

increases (Wang 1986 and Sommer et al. 1997).

    Splittail are benthic (bottom) foragers. In Suisun Marsh, they feed 

primarily on opossum shrimp (Neomysis mercedis, and presumably, the 

exotic Acanthomysis spp. as well), benthic amphipods (Corophium), and 

harpactacoid copepods, although detrital (non-living and detached 

organic) material makes up a large percentage of their stomach contents 

(Daniels and Moyle 1983). In the Delta, clams, crustaceans, insect 

larvae, and other invertebrates also are found in the diet. Predators 

include striped bass (Morone saxatilis) and other piscivores (Moyle 


    In recent years, splittail have been found most often in slow 

moving sections of rivers and sloughs and dead-end sloughs (Moyle et 

al. 1982, Daniels and Moyle 1983). Reports from the 1950s, however, 

mention Sacramento River spawning migrations and catches of splittail 

during fast tides in Suisun Bay (Caywood 1974). Because they require 

flooded vegetation for spawning and rearing, splittail are frequently 

found in areas subject to flooding. Historically, the major flood 

basins distributed throughout the Sacramento and San Joaquin valleys 

provided spawning and rearing habitat. These flood basins have all been 

reclaimed or modified for flood control purposes (e.g., Yolo and Sutter 

bypasses). Although primarily a freshwater species, splittail can 

tolerate salinities as high as 10 to 18 parts per thousand (ppt) (Moyle 

1976, Moyle and Yoshiyama 1992). California Department of Fish and Game 

(CDFG) survey data from 1979 through 1994 indicate that the highest 

abundances occurred in shallow areas of Suisun and Grizzly bays.

    Recent research indicates that splittail will use the Yolo and 

Sutter bypasses during the winter and spring months for foraging and 

spawning (Sommer et al. 1997). However, the Yolo Bypass may only be 

used by splittail during wet winters, when water from the Sacramento 

River over-tops the Fremont Weir and spills over the Sacramento Weir 

into the Bypass. In 1998, the Yolo and Sutter bypasses provided good 

habitat for fish, particularly splittail, when they were flooded for 

several weeks in March and April. In order to provide spawning habitat 

for splittail, water must remain on the bypasses until fish have 

completed spawning, and larvae are able to swim out on their own, 

during the draining process.

    The decline in splittail abundance has taken place during a period 

of increased human-induced changes to the seasonal hydrology of the 

Delta, especially the increased exports of freshwater. These changes 

include alterations in the temporal, spatial, and relative ratios of 

water diverted from the system. These hydrological effects, coupled 

with severe drought years, introduced aquatic species, the loss of 

shallow-water habitat to reclamation activities, and other human-caused 

actions, have reduced the species' capacity to recover from natural 

seasonal fluctuations in hydrology for which it was adapted.

    Analyses of survey data collected from 1967 to 1993 (Meng 1993, 

Meng and Moyle 1995) and data from 1967 to 1997 by Service, CDFG, and 

University of California at Davis biologists from several different 

studies indicate the following results--(1) Overall, splittail 

abundance indices have declined. Meng and Moyle (1995) demonstrated 

that on average, splittail have declined in abundance by 60 percent 

through 1993. The CDFG updated these data to include the most current 

data available and provided to the Service. The CDFG calculated the 

data using the updated information. The results were similar. These 

updated data demonstrate that on average, splittail have declined 

significantly in abundance by 50 percent since 1984. The greatest 

declines (over 80 percent) were found from studies that sampled the 

shallow Suisun Bay area, the center of the range of the species (Meng 

and Moyle 1995). The updated information also show a significant 

decline (43 percent) for the studies that sampled the shallow Suisun 

Bay area. A study that began in 1980 in the lower Estuary, at the 

outermost edge of splittail range, found the lowest percent decline (20 

percent) (CDFG unpublished data) through 1993. The analysis completed 

on the updated data also showed the smallest decline for this study (6 

percent). The number of splittail young taken at State and Federal 

pumping facilities (measured as number of individuals per acre-foot of 

water pumped), as of 1993, had declined 64 percent since 1984. With the 

updated data, the number of splittail young taken at State and Federal 

pumping facilities demonstrated a 97 percent increase. This percent 

increase is due to the unusually high salvage that occurred during 


    We estimate splittail populations to be 35 to 60 percent of what 

they were in the 1940s, and these estimates may be conservative (Moyle 

in prep). CDFG midwater trawl data indicate a decline from the mid-

1960s to the late 1970s, followed by a resurgence, with yearly 

fluctuations, through the mid-1980s. From the mid-1980s through 1994, 

splittail numbers have declined in the Delta, with some small increases 

in various years. This decline is also demonstrated in the updated CDFG 


    (2) Overall splittail abundances vary widely among years. Sommer et 

al. 1997 also found that splittail recruitment success fluctuates 

widely from year to year and over long periods of time. During dry 

years abundance is typically low. During the dry years of 1980, 1984, 

1987, and 1988 through 1992, splittail abundance indices for young-of-

the-year were low, indicating poor spawning success. Additionally, all 

year class abundances were low during these years. In 1994, the fourth 

driest year on record, all splittail indices were extremely low.

    We believe wet years provide essential habitat for splittail and 

allow populations to rebound from dry years. Successful reproduction in 

splittail is often highly correlated with wet years. Large pulses of 

young fish were observed in wet years 1982, 1983, 1986, and 1995. In 

1995, one of the wettest years in recent history, an increase in all 

indices was recorded, as in 1986, which was another wet year following 

a dry year. However, young of the year taken per unit effort (for 

example, either the number of fish per net that is towed or

[[Page 5965]]

the number of fish per volume of water sampled) has actually declined 

in wet years, steadily from a high of 12.3 in 1978 to 0.3 in 1993. The 

updated data from CDFG demonstrate this same decline in wet years, from 

37.3 in 1978 to 0.6 in 1993. The abundance indices of splittail during 

the years of 1995, 1996, and 1997 were 44.5, 2.1, and 2.6, 

respectively. Year 1995 was a very wet year and splittail abundances 

were high. Years 1996 and 1997 were wet years, yet abundance indices 

were low. However, overall splittail declines remain high (82 percent/

43 percent with updated data) in the shallow-water Suisun Bay area, the 

center of its distribution.

    We believe high abundance indices in 1995 are an artifact of the 

highly unusual hydrological conditions that occurred. Therefore, we 

also calculated all of the percent declines, as stated above, without 

the 1995 abundance indices in the analysis. The overall decline is 67 

percent. The decline from the studies in the shallow Suisun Bay area 

without 1995 is 80 percent. For the study in the lower Estuary, the 

decline is 39 percent. The salvage data collected at both the State and 

Federal pumping facilities demonstrate a 22 percent decline. Other than 

1995, the salvage data include 1996 and 1997.

    (3) A strong relationship exists between young-of-the-year 

abundance and outflow (i.e., river outflow into San Francisco Bay after 

water exports are removed). As outflow increases, annual abundance of 

young-of-the-year splittail increases. Changes in outflow explain 55 to 

72 percent of the changes seen in young-of-the-year splittail 

abundance, depending on which survey data are analyzed.

    (4) Splittail are most abundant in shallow areas of Suisun and 

Grizzly bays where they generally prefer low-salinity habitats. 

Salinities in Suisun and Grizzly bays increase when, as a result of 

water exports or drought conditions, the mixing zone (the freshwater-

saltwater interface) shifts upstream.

    (5) Concentration of splittail in shallow areas suggests that they 

are particularly vulnerable to reclamation activities, such as 

dredging, diking, and filling of wetlands.

    The above data indicate that splittail abundances vary widely in 

response to environmental conditions, but the general population 

numbers are declining. The following are some reasons why the species 

is in decline. The splittail is primarily threatened by the altered 

hydraulics and reduced Delta outflow caused by the export of freshwater 

from the Sacramento and San Joaquin rivers through operation of the 

State and Federal water projects. These operations include not only the 

export of water from the Delta but also diversion of water to storage 

during periods of high run-off, which reduce instream flows and 

available submerged aquatic habitat for spawning and rearing. 

Additional threats to this species include--

    (1) Direct and indirect mortality at power plants and in-Delta 

water diversion sites;

    (2) Reduced river flows and changes in the seasonal patterns of 

flows in the Sacramento and San Joaquin rivers and their tributaries;

    (3) The loss of spawning and nursery habitat as a consequence of 

draining and diking for agriculture;

    (4) The loss of shallow-water habitat due to levee slope 

protection, marina construction, and other bank oriented construction 


    (5) The reduction in the availability of highly productive 

brackish-water habitat;

    (6) The presence of toxic substances, especially agricultural and 

industrial chemicals and heavy metals in their aquatic habitat;

    (7) Human and natural disturbance of the food web through altered 

hydrology and introduction of exotic species;

    (8) Flood control operations that strand eggs, larvae, juveniles, 

and adults;

    (9) The increase in severity of these effects by six years of 

drought; and

    (10) Entrainment (pulling) of fish through unscreened or 

inadequately screened municipal and agricultural diversions.

Previous Federal Action

    We included the Sacramento splittail as a category 2 candidate 

species for possible future listing as endangered or threatened in the 

January 6, 1989, Animal Notice of Review (54 FR 554). Category 2 

candidates were defined as those species for which information in our 

possession indicated that proposing to list as endangered or threatened 

was possibly appropriate, but for which conclusive data on biological 

vulnerability and threats were not currently available to support 

proposed rules. We discontinued the use of multiple candidate 

categories on February 28, 1996 (61 FR 7596), and species meeting the 

definition of the former category 2 are no longer considered 


    On November 5, 1992, we received a petition from Mr. Gregory A. 

Thomas of the Natural Heritage Institute to add the Sacramento 

splittail to the List of Endangered and Threatened Wildlife and to 

designate critical habitat for this species in the Sacramento and San 

Joaquin rivers and associated estuary. Mr. Thomas identified eight 

organizations as co-petitioners, including the American Fisheries 

Society, the Bay Institute of San Francisco, the Natural Heritage 

Institute, the Planning and Conservation League, Save San Francisco Bay 

Association, Friends of the River, the San Francisco Baykeeper, and the 

Sierra Club. We published a 90-day finding on July 6, 1993 (58 FR 

36184), that the petition presented substantial information indicating 

that the requested action may be warranted. We initiated a status 

review and analyzed available data on this species (Meng 1993).

    On January 6, 1994, we published a proposed rule to list the 

splittail as a threatened species and requested public comment (59 FR 

862). The proposed rule constituted a 12-month finding that the 

petitioned action was warranted, in accordance with section 4(b)(3)(B) 

of the Act.

    On January 10, 1995, we published in the Federal Register (60 FR 

2638) a notice of a 6-month extension to make a final listing 

determination and reopened a 45-day public comment period on the 

proposed rule to list the splittail. The basis for this extension was 

to address differences of scientific opinion concerning the status of 

splittail upstream of the Delta, especially the existence of a resident 

population upstream of the Delta. In April 1995, subsequent to the 

close of the extension period, a moratorium on the processing of all 

final listing proposals was established by Congress in Public Law 104-

6. The moratorium was lifted on April 26, 1996. As mandated by the 

moratorium, we conducted no actions to finalize the proposed rule 

during the period April 1995 to April 1996.

    As described in detail below, we reopened the comment period on May 

18, 1998. We solicited the latest information regarding the abundance 

and distribution of the species. Additionally, we requested comments 

concerning the publication, ``Resilience of Splittail in the 

Sacramento-San Joaquin Estuary'' (Sommer et al. 1997).

    The processing of this final rule follows our final listing 

priority guidance for fiscal years 1998 and 1999 published in the 

Federal Register on May 8, 1998 (63 FR 25502). The guidance clarifies 

the order in which we will process rulemakings giving highest priority 

(Tier 1) to processing emergency rules to add species to the Lists of 

Endangered and Threatened Wildlife and Plants; second priority (Tier 2) 

to processing final determinations on proposals to add

[[Page 5966]]

species to the lists, processing new listing proposals, processing 

administrative findings on petitions (to add species to the lists, 

delist species, or reclassify listed species), and processing a limited 

number of proposed and final rules to delist or reclassify species; and 

third priority (Tier 3) to processing proposed and final rules 

designating critical habitat. Processing of this final rule is a Tier 2 


Summary of Comments and Recommendations

    In the January 6, 1994, proposed rule (59 FR 862), we requested all 

interested parties to submit factual reports or information, that might 

contribute to the development of a final rule. We contacted State 

agencies, county governments, Federal agencies, scientific 

organizations, and other interested parties and requested comments. We 

held public hearings on the proposed splittail listing in conjunction 

with hearings on two other proposed Federal actions, the designation of 

critical habitat for delta smelt (Hypomesus transpacificus) (59 FR 

852), and the United States Environmental Protection Agency's (USEPA's) 

water quality standards for the Estuary (59 FR 810). We published 

newspaper notices of the public hearings on February 4, 1994, in the 

Sacramento Bee, Fresno Bee, Los Angeles Times, and San Francisco 

Chronicle, all of which invited general public comment. We held public 

hearings on February 23, 1994, in Fresno; on February 24, 1994, in 

Sacramento; on February 25, 1994, in San Francisco; and on February 28, 

1994, in Irvine. At each meeting, we took testimony from 1 p.m. to 4 

p.m. and 6 p.m. to 8 p.m.

    During the 3-month comment period from January 6 to March 7, 1994, 

we received comments (i.e., letters and oral testimony) from 133 

individuals, organizations, or government agencies. Many of these 

comments were given at joint public hearings for the combined Federal 

rulemaking package for the Sacramento-San Joaquin Delta (including the 

proposal to list the Sacramento splittail, the proposal to designate 

critical habitat for the delta smelt, and final water quality standards 

for the Delta being proposed by the USEPA). Only 13 of the 133 

commenters addressed the proposed rule to list the Sacramento 

splittail. Four of the 13 commenters that specifically addressed the 

proposed rule to list the Sacramento splittail provided oral testimony 

at the public hearings. Of the 13 commenters mentioned above, nine 

supported the listing of the splittail, two opposed the listing, and 

others provided comments considered as neutral. Five conservation 

organizations (or branches thereof), one sport fishing organization, 

two interested parties, and a Federal agency (the Bureau of Reclamation 

(BOR)) supported the proposed listing. The California Department of 

Water Resources (DWR) and the State Water Contractors opposed the 

proposed listing. We received no additional expert opinions from 

independent specialists concerning pertinent scientific or commercial 

data about the splittail.

    On August 4, 1994, we received a letter dated August 3, 1994, from 

the State Water Contractors requesting a 6-month extension on the 

listing determination. The reasons provided in the request for 

extension were the same as those submitted during the public comment 

period, addressed below.

    We granted a 6-month extension to address the status of splittail 

upstream of the Delta, and the importance of any such splittail to the 

population as a whole. Therefore, we reopened the public comment period 

for 45 days, beginning January 10, 1995, and ending February 24, 1995. 

During this second comment period we received one additional comment 

letter that opposed the listing of the splittail. The comment letter 

addressed this issue in part.

    On March 19 and March 20, 1998, the DWR and the State Water 

Contractors, respectively, requested the comment period be reopened. 

The basis of this request was that substantial data had been collected 

since 1995 regarding the abundance and distribution of the splittail. 

We believe that consideration of this and any new information is 

significant to the final determination of the status of the Sacramento 

splittail. For this reason, we sought information concerning abundance 

and distribution data for this species from 1995-1997. Specifically, we 

sought comments regarding information presented in the publication, 

``Resilience of Splittail in the Sacramento-San Joaquin Estuary'' 

(Sommer et al. 1997), and how the results affect our recommendation for 

listing the Sacramento splittail as a threatened species. The comment 

period was opened on May 18, 1998, and closed on July 17, 1998. We 

received comments from eight respondents, whose comments are summarized 


    The written comments and oral statements, questioning or opposing 

the listing of the splittail, or otherwise providing information, 

obtained during the public hearings and comment periods are combined 

into general issues that are summarized, discussed and responded to 

below. Most of the comments supporting the listing did not provide any 

additional information, so we have not prepared a discussion or 

response to these comments.

    Issue 1: A respondent commented that our statement about splittail 

decline was based on data regarding splittail juveniles. The respondent 

argued that adult splittail are abundant and that our reliance on a 

limited portion of the year classes for a listing determination is 


    Service Response: We have reviewed the seven data sets used in the 

status review (Meng 1993). These data sets include--(1) a fall midwater 

trawl survey in the upper Estuary by CDFG; (2) a monthly midwater and 

otter trawl in the lower Estuary by CDFG (San Francisco Bay-Outflow 

Study, hereafter Bay Study); (3) a monthly otter trawl survey of Suisun 

Marsh (a tidal marsh next to Suisun Bay) by the University of 

California; (4) a midwater trawl survey that we conducted at Chipps 

Island in Suisun Bay; (5) a midwater trawl survey that we conducted in 

the Sacramento River; (6) a beach seine survey that we conducted in the 

Delta and Sacramento River; and (7) fish salvage data collected by CDFG 

and the BOR at the State and Federal pumping facilities located in the 

south Delta. The beach seine survey and Sacramento River midwater trawl 

were not used in the analysis of abundance trends because several years 

of data were missing. (See next comment for criteria used to identify 

data sets suitable for inclusion in abundance trend analysis.) Of the 

surveys that were used to establish abundance trends, ratios of young-

of-the-year to adults were approximately equal for three out of five 

surveys (fall midwater trawl, Bay Study, and Suisun Marsh). Of the 

remaining surveys, the Chipps Island trawl was dominated by young-of-

the-year, and fish salvage sampled five times as many young as adults. 

We calculated percent declines independently for each survey. When the 

two surveys dominated by young-of-the-year are removed from the 

analysis, overall average percent decline remains the same. Therefore, 

the contention that splittail adults are abundant, and that our 

analysis relied on a particular age-class of the species, is unfounded.

    Issue 2: One respondent maintained that the studies we relied on 

were limited geographically (i.e., to the Estuary) and that splittail 

may occupy a wider range. Conversely, another respondent commented that 

the Estuary is the principal habitat of splittail and virtually all 

splittail are found in the Estuary for the first 2 years of their 


[[Page 5967]]

There was also disagreement about the gear types used for sampling. One 

respondent held that they were not appropriate, whereas another 

respondent stated that gear used by the studies, (i.e., bottom and 

midwater trawls) captured all sizes of splittail. The respondent that 

questioned gear suitability also commented that studies used in the 

listing determination were designed to capture striped bass, were 

limited in their ability to sample shallow and inshore habitats, and 

that the use of the CDFG abundance index was inappropriate.

    Service Response: We used several criteria to determine if a data 

set could be incorporated into the analysis of trends in splittail 

abundance and distribution. Data had to be collected for at least 10 

consecutive years and effort had to be relatively constant or a core 

data set had to be available to extract for analysis. A core data set 

of at least 10 consecutive years provides the necessary information to 

conduct an analysis of long term trends in abundance. One respondent 

referred to the use of two data sets that sampled upstream of the 

Estuary. These data sets were not included in the analysis of abundance 

trends because time of year of sampling varied, sampling sites varied, 

and some years of sampling were missing. These data sets were examined 

however, for trends in distribution, and showed that capture of 

splittail decreased as sampling was conducted further upstream from the 

Estuary. One of the surveys referred to by the respondent consists of 

samples taken upstream of the Delta and catches young-of-the-year 

almost exclusively. Because splittail migrate upriver to spawn in the 

spring (Meng and Moyle 1995), it is likely that these catches are the 

offspring of splittail that reside further downstream for the remainder 

of the year.

    Regarding gear suitability, a respondent suggested that certain 

gear used, especially tow nets and trawls, were not appropriate for 

sampling splittail because of their benthic habits and preference for 

shallow water. The respondent also referred to gillnetting as an 

effective method for capturing splittail.

    We agree that the summer townet survey is inefficient in sampling 

splittail and therefore, was not included in the analysis of abundance. 

However, several trawling methods were included. Meng (1993) compared 

the effectiveness of three types of gear from one survey--bottom 

(otter) trawls, midwater trawls, and beach seines. Bottom and midwater 

trawls sampled equal proportions of all splittail year classes (i.e., 

young-of-the-year, fish 1 year or older, and fish 2 years or older). 

The beach seine was selective for young-of-the-year. High catches of 

young-of-the-year in midwater trawls are thought to reflect movement of 

young out of near shore areas when water recedes. They are frequently 

captured in channels, presumably as they move downstream (Meng and 

Moyle 1995). The information outlined above suggests that regularly 

repeated bottom and midwater trawls are reasonably effective for 

sampling splittail and examining trends through time.

    There are no long-term gillnetting data sets that meet the criteria 

above for inclusion in the analysis of abundance. Furthermore, 

gillnetting results in high fish mortality, and long-term sampling by 

gillnet is not feasible in waters with sensitive species. Almost all 

sampling techniques have biases. For the data used in the abundance 

analysis, the sampling remained constant. Therefore, the biases 

remained constant through time, and there was a consistent downward 

trend in splittail abundance.

    Most of the sampling programs in the Estuary were initiated to 

track changes in striped bass or salmon (Oncorhynchus tshawytscha) 

populations. These long term data sets can be used to assess changes in 

abundance of other species as long as assumptions of sampling design 

are considered. Limitations of surveys designed for striped bass or 

salmon have been consistent through time. Problems with sampling 

shallow and inshore habitats have not changed and should not affect 

relative abundance trends. Therefore, trends or changes in splittail 

abundance reflected by these surveys should be unaffected by the 

various weaknesses identified by the respondent. The high correlation 

between the CDFG abundance index and numbers of fish (83 percent of the 

variability is explained) suggests that the index is a reasonable 

estimator of population trends.

    Issue 3: One respondent commented that three separate data sets, 

including a gillnet survey, suggest that splittail are abundant 

throughout the Delta. Another respondent countered that gillnetting 

surveys cited as evidence of abundance were based on a single night of 

sampling in the American River when splittail were presumably 

concentrated for spawning. This respondent added that the 60 percent 

decline cited in the proposed rule is remarkable because one strong 

year class (such as occurred in 1983) can mask an overall decline in 

this long-lived species.

    Service Response: The Act requires us to base listing 

determinations upon best available scientific and commercial data. The 

three data sets referred to by the respondent are limited temporally 

and geographically. One of the data sets referred to by the respondent 

covers one night of gillnet sampling in one location. The other two 

data sets refer to 2 years of sampling, separated by more than 10 

years, at the Pacific Gas and Electric plant in Antioch. We considered 

all available data but determined that incorporation of sporadic or 

isolated sampling events was not appropriate because of problems 

associated with drawing conclusions from limited or sporadic data.

    Issue 4: A respondent commented that no data were provided to 

support the conclusion that successful reproduction is highly 

correlated with wet years.

    Service Response: Regression analyses of splittail young abundance 

versus spring outflow (February-May) show strong relationships. As 

spring outflow increases, abundance of splittail young increases. 

Changes in spring outflow explained varying percentages of changes in 

abundance of splittail young and ranged from 55 to 72 percent, 

depending on which survey data were analyzed (Meng and Moyle 1995). All 

of the regression analyses were significant (probability values ranged 

from less than 0.0001 to 0.0025) (Meng and Moyle 1995). This is a 

strong correlation between successful reproduction and wet years. The 

low and high abundance indices of juvenile abundance from 1994 and 

1995, respectively, is consistent with this analysis.

    Issue 5: One respondent commented that the data we used to 

determine the decline of splittail was biased by the fact that the time 

period used to determine pre-decline and post-decline was heavily 

weighted with wet years in the pre-decline period, thereby biasing the 


    Service Response: We analyzed only wet years to determine if there 

had been a decline within that year type. That analysis indicated that 

even in wet years, when one would anticipate substantially higher 

recruitment, there had been an overall decline in splittail abundance. 

Young-of-the-year abundance declined steadily in the annual Chipps 

Island trawl in wet years from 1978 to 1993. Abundance in 1993 was less 

than 3 percent of what it was in 1978. Abundance per unit effort was 

approximately 12.3 in 1978, 8.1 in 1982, 2.0 in 1983, 1.3 in 1986 and 

less than 0.3 in 1993. This first analysis was done using a catch-per-

tow analysis. The second analysis of splittail abundance using a 

different analytical method that was based on a catch-per-volume of

[[Page 5968]]

water sampled yields a similar result. The volumetric methodology 

yields a catch per unit effort (CPUE) at the Chipps Island trawl site 

of 2.6 in 1978, 0.97 in 1982, 0.77 in 1983, 0.73 in 1986, and 0.21 in 

1993. These two analyses show that there is an overall reduction in 

abundance that is not solely a result of drought conditions. Using the 

second analytical method yields a CPUE for 1995 and 1996 of 2.1 and 

0.63 respectively, which were both wet years. If there were a stable 

number of sexually mature fish throughout the period of decline, one 

would expect similar reproduction in both years. However, there was a 

substantial decline from 1995 to 1996, which may indicate that there 

were not as many adult fish, reflected by the lower CPUE in 1996.

    Issue 6: One respondent commented that there is no evidence to 

support the statement that lower numbers of splittail young-of-the-year 

during the drought may affect the stock's ability to recover.

    Service Response: Our status report (Meng 1993) and the proposed 

rule (59 FR 862) indicated that wet years are required for splittail 

recruitment. However, as previously discussed in the analysis of only 

wet years, young-of-the-year abundance has declined during these years. 

Because splittail live 5 to 7 years and rely on wet years for strong 

year classes, a prolonged drought, such as the recent 6-year drought, 

may provide little recruitment opportunities. The steady decline in 

young-of-the-year abundance in the Chipps Island trawl, combined with a 

5 to 7 year life span and reliance on wet years for strong year 

classes, suggests that lower numbers of splittail young during the 

drought will reduce the number of adult fish in subsequent wet years. 

This overall decline in splittail abundance, even during wet years, may 

affect the ability of the species to recover.

    Issue 7: A respondent commented that the drought, not exports, was 

responsible for the recent decline in splittail abundance indices.

    Service Response: Water exports at the State and Federal pumping 

facilities are not the only threat to the species related to the State 

Water Project and the Central Valley Project. The State and Federal 

water projects are interbasin water delivery systems that include 34 

reservoirs, thousands of miles of aqueducts and canals, and large 

pumping facilities in the south Delta. Storage in reservoirs and 

conveyance components of the projects also have substantial effects on 

the splittail. Outflow conditions that inundate large vegetated areas 

are affected by pumping because increases in pumping must be supported, 

at some point, by increases in diversions to State and Federal 

reservoirs. Most rainfall occurs during winter and spring in 

California, and high spring flows are augmented by snow melt. 

Historically, high spring flows provided flooded areas and shallows for 

fish spawning and rearing. Construction of upstream reservoirs allowed 

large amounts of these high spring flows to be diverted to storage for 

later release. Diversion of water to storage dampens peak spring flows 

beneficial to splittail spawning success and provides water for pumping 

when flows to the Estuary decrease.

    Since 1983, the proportion of water exported from the Delta during 

October through March has been higher than in earlier years (Moyle et 

al. 1992). Changes in timing and amounts of exports, as well as 

operations of upstream water storage facilities, affect fish migration 

and spawning habits. Dampening of peak spring flows by springtime 

diversions to storage to replenish depleted reservoirs has deleterious 

effects on estuarine species such as splittail, which evolved in a 

system with periodic spring flooding.

    As previously discussed, in wet years when fish production is 

generally high, large segments of the juvenile population are 

vulnerable to export facilities both directly and indirectly through 

entrainment and altered Delta hydrology. This vulnerability is 

reflected in wet year abundance indices. The adverse effects of the 

pumps in wet years combined with poor recruitment during dry years 

exacerbates the population demographic outlook for the splittail.

    Issue 8: A respondent commented that calculations in the status 

report were incorrect. This comment targeted a reference in the 

proposed rule regarding the abundance of splittail in the Suisun Bay 


    Service Response: This comment was apparently based on a 

misinterpretation of data included in the status report. The respondent 

incorrectly assumed that the top half of Figure 13 in the status report 

supported statements in the text regarding abundance of splittail in 

Suisun Bay. However, this portion of Figure 13 was intended to indicate 

the approximate locations and effort of the different surveys used for 

the status report. The bottom half of Figure 13 was intended to support 

statements about abundance of splittail in the Suisun Bay area. The 

respondent acknowledged the high catches in Suisun and Grizzly bays 

represented in the bottom of Figure 13. Furthermore, two CDFG surveys 

indicate that abundance of splittail captured by each survey, 

comprising 72 and 56 percent of the catch, respectively, was taken in 

those areas (Meng and Moyle 1995).

    The respondent also stated that values used to construct the top 

half of Figure 13 were incorrect. The respondent recalculated the 

values, but used incomplete data sets (Chipps Island trawl) or 

incorrect data sets (Suisun Marsh). Furthermore, the respondent 

referred to Bay Study beach seine data that were not included in the 

analysis and constructed a table of values without using the 

appropriate scale included on the original figure. The respondent 

stated that adding ratios, as in Figure 13, violates basic laws of 

algebra. However, the figure was not intended to show the sums of 

catches in different areas. The figure was intended to illustrate the 

relative contributions of different surveys in different areas. The top 

half of Figure 13 has been removed from the status report because it 

was confusing and did not contribute to the analysis.

    Issue 9: Two respondents commented that outflow conditions that 

inundate large vegetated areas and result in favorable spawning 

conditions are largely unaffected by diversion and export capabilities 

of the State and Federal water projects.

    Service Response: Evidence offered to support this comment is a 

correlation analysis performed by DWR indicating that there is a 

positive relationship between the number of days that the Yolo and 

Sutter bypasses are flooded and splittail young abundance. The Yolo and 

Sutter bypasses are flood control structures that bypass flows 96 and 

128 km (60 and 79 mi) upstream of the confluence of the Sacramento and 

San Joaquin rivers respectively. Because high outflows and number of 

days the bypasses are flooded are strongly correlated, it is difficult 

to isolate flooding of these specific areas as the most important 

factor influencing splittail abundance. Although flooding of the 

bypasses may result in favorable spawning conditions, young located in 

the bypasses are likely to experience high mortality because they 

become trapped in depressions and agricultural drainage canals when 

water recedes (Jones and Stokes 1993).

    Issue 10: One respondent commented that the effects of entrainment 

on splittail are questionable. The respondent questioned statements in 

the proposed rule that splittail may be more vulnerable to the effects 

of entrainment in water project facilities in dry years. The respondent 

based the argument on strong relationships between splittail abundance 

and losses to project operations.

[[Page 5969]]

    Service Response: An entrainment index was developed (a ratio of 

indices from two surveys, i.e., salvage of entrained fish at water 

project facilities divided by the fall midwater trawl index) that 

demonstrated entrainment of splittail young was higher in wet years. We 

acknowledge that based on the two surveys comprising the entrainment 

index, entrainment of splittail appears to occur in proportion to 

abundance, that is, entrainment is higher in wet years. Because 

splittail abundance relies on high levels of recruitment in wet years, 

taking more splittail in wet years does not remove the threat of 

entrainment in water project facilities from the population. In the 

early 1980s, hundreds of thousands of splittail young were salvaged 

monthly by the State export facility alone (this number has decreased 

as abundance has decreased). Since splittail abundance relies on strong 

year classes in wet years to support the population during poor 

environmental conditions, entrainment of large numbers of young, even 

in proportion to abundance, remains a threat.

    With the exception of the Bay Study, all 1995 indices were less 

than historic wet year indices or, in the case of the Fall-midwater 

Trawl survey, not as high as pre-decline wet-year indices. However, the 

combined CVP/SWP salvage was more than double any previous year's 

salvage index, wet or dry (approximately 8 million young-of-the-year 

fish for the entire year versus less than 4 million young-of-the-year 

fish in 1986, which was the next highest entrainment index on record). 

This suggests that during 1995, the CVP/SWP export facilities in the 

Delta may have actually entrained fish in greater proportion to 

abundance than in past years.

    Issue 11: One respondent questioned the mechanism by which shallow 

water habitat has been lost in recent years. The respondent stated that 

a significant amount of marsh habitat was diked and drained in the 

first part of this century, but relatively little reclamation of 

wetlands occurred within the last decade.

    Service Response: We acknowledge that most wetland losses in the 

Estuary occurred in the first part of this century. The recent loss of 

shallow water habitat in the Estuary is due to increasing salinities in 

Suisun Bay, a shallow area. Suisun Bay was historically fresh to 

brackish much of the year and important for the rearing of Delta 

fishes. Increasing salinities in the Suisun Bay area due to decreases 

in outflow have reduced available shallow water habitat for splittail, 

primarily a freshwater species. Increasing salinities in this area have 

also decreased Neomysis mercedis production, a primary splittail food 

and a factor cited by the respondent as being a possible cause of 


    Issue 12: One respondent commented that the possible effects of 

predators and competitors deserves greater consideration. The 

respondent referred to three introduced species that have experienced 

population explosions during the same period that splittail declined, 

two gobies and one atherinid, the inland silverside (Menidia 


    Service Response: We acknowledge that the three introduced species 

and the splittail may occupy similar habitats. However, these 

introduced species rarely exceed 8 cm (3.4 in) in length as adults, 

one-fifth the size of splittail. Thus, direct predation by the 

introduced species on splittail is unlikely. It is also unlikely that 

adults of the introduced species consume splittail young because of 

differences in spawning sites, that is, many splittail spawn upstream 

of and in the upper portions of the Estuary. Furthermore, competition 

for food or resources (such as spawning sites) is unlikely and would be 

difficult to extract from the wide array of factors that may affect 

splittail. The introduced species most likely to affect splittail is 

striped bass, which is known to favor splittail for food (see Factor C 

in the ``Summary of Factors Affecting the Species'' section). Splittail 

and striped bass, however, have coexisted for decades in the Estuary. 

Recent declines in splittail have occurred in concert with striped bass 


    Issue 13: A respondent stated that the reason for our decision not 

to designate critical habitat is not entirely clear from the proposed 

rule. Further, the respondent expressed concern that we provide 

splittail with a level of protection afforded by listing the species as 

threatened pursuant to the Act rather than addressing threats to the 

species in recovery work that is already being undertaken for Delta 

fisheries in general.

    Service Response: We clarify the decision not to designate critical 

habitat in the ``Critical Habitat'' section of this rule. Based on our 

analysis of threats, including the lack of recovery efforts implemented 

and regulatory controls, we determined threatened status for the 

splittail in this rule. The Sacramento San-Joaquin Delta Native Fishes 

Recovery Plan (U.S. Fish and Wildlife Service 1996) discusses threats 

and needed restoration actions in detail.

    Issue 14: One respondent questioned the need to list splittail with 

current protections in place for delta smelt and proposed USEPA water 

quality standards for the Estuary (59 FR 810). The respondent stated 

that increases in water demand for splittail would affect the 

predictability of water supplies for other users.

    Service Response: In determining to list the splittail, we 

considered the effects of the listing of delta smelt and designation of 

critical habitat for the delta smelt (60 FR 4664) as well as 

implementation of the State's Water Quality Control Plan (WQCP). We 

believe that the life history and habitat requirements of splittail 

will not be satisfied by these actions.

    The life history characteristics and habitat usage of splittail 

differ from those of delta smelt. Splittail migrate farther upstream to 

spawn in the Sacramento and San Joaquin rivers and their tributaries 

than do delta smelt. Consequently, protections for this species will 

not overlap completely with those needed for splittail. Splittail also 

differ from the already listed species in their habitat usage. Because 

splittail prefer shallow water, with emergent vegetation, they are 

particularly threatened by reclamation, dredging, and development 

activities in those habitat types. Finally, because splittail are long-

lived and spend much of their lives in the Estuary, contaminants pose a 

greater threat to this species than to delta smelt.

    As described in detail under Factor D of the ``Summary of Factors 

Affecting the Species'' section, water quality objectives developed by 

the SWRCB could benefit splittail. In 1995, the SWRCB adopted a WQCP 

for the San Francisco Bay/Sacramento-San Joaquin Delta Estuary (95-1WR, 

May 1995) to protect water quality and to control water resources that 

affect the beneficial uses of the Bay-Delta Estuary. As an interim 

implementation measure, the SWRCB adopted Water Rights Order 95-6, 

which relies on the CVP and SWP to comply with the new standards. The 

flows identified in the water rights decision 95-6 that were 

implemented through section 7 of the Act with the BOR and USEPA were 

intended to benefit splittail as well as delta smelt. These flows would 

provide spawning flows in tributaries as well as habitat and transport 

flows in and through the Delta if the WQCP is fully implemented. 

However, this WQCP has not proven entirely adequate to protect against 

the effects of entrainment both at the CVP/SWP export facilities and 

other agricultural and municipal water diversions. For example, 

operations of the CVP and SWP facilities were altered only slightly for 

a 3-day period of time

[[Page 5970]]

in June of 1995 to reduce the effects of salvage on out-migrating 

juvenile splittail. This action was taken after almost 6 million 

juvenile splittail were entrained and salvaged at the State and Federal 

export facilities in the spring of 1995. Between the middle of April 

and the end of June, over 6.3 million juvenile fish were salvaged at 

these facilities. Based on data that we received from ongoing 

monitoring programs during 1995, the vast majority of the fish were 

probably of San Joaquin River origin, where substantial spawning has 

not occurred in over a decade. The monitoring programs showed little 

juvenile production and out migration from the Sacramento River. Even 

if a population exists upstream of the Delta, State and Federal project 

operations have done little, even in this new regulatory environment, 

to protect against entrainment of those fish. Additionally, exports 

during the out migration period change the behavioral cues and 

hydrology that may affect the ability of juveniles to move out of the 


    Moreover, the SWRCB has not completed the development of a long 

term implementation plan for the 1995 WQCP. The SWRCB has prepared a 

draft Environmental Impact Statement that evaluates a range of 

potential alternative actions so that responsibility to meet the water 

quality objectives in the 1995 WQCP can be allocated. The SWRCB is 

currently holding hearings to obtain all necessary information so that 

an implementation plan can be developed. An experimental proposal has 

been developed by stakeholders on the San Joaquin River along with the 

Service and other State and Federal agencies. The proposal, known as 

the Vernalis Adaptive Management Plan (VAMP), would evaluate the 

effects of flow and exports on salmon, along with a barrier at the head 

of Old River, for the next 12 years. It may be accepted by the SWRCB 

and may provide some benefit to splittail, but full evaluation of the 

benefits and impacts to the species will not occur until the experiment 

is complete. We will participate in the implementation of VAMP.

    Issue 15: Several respondents questioned our reliance on the 

entrapment zone (the area of the Estuary where saltwater and freshwater 

meet) and its importance to splittail. Another respondent questioned 

our reliance on changes in salinity and shifts in the distribution of 

splittail upstream concurrent with shifts in the salinity.

    Service Response: We agree that there is little if any correlation 

between splittail abundance and the entrapment zone. However, the 

entrapment zone is an important ecological indicator. It provides an 

area in the estuary that is highly productive. However, when located 

upstream, the mixing zone is not as productive because it is confined 

to deep river channels where the total surface area is smaller, fewer 

shoal areas exist, water currents are swifter and more turbulent, and 

zooplankton productivity is low.

    Issue 16: One respondent commented that we could not support the 

conclusion that all size classes of splittail suffer near total loss at 

the export facilities due to entrainment.

    Service Response: According to salvage facility personnel, juvenile 

splittail may suffer up to 50 percent mortality due to salvage at the 

facilities (Scott Barrow, CDFG, pers. comm. 1995). Other forms of 

mortality exist due to screen efficiency, predation, and impingement 

that are not quantifiable at this time. We have modified the rule 


    Issue 17: Several commenters raised the issue of peer review of the 

data and conclusions. One commenter also stated that there was no 

public access to the data.

    Service Response: The proposed rule to list the splittail was 

published on January 6, 1994, prior to the time that the interagency 

policy on peer review (59 FR 126) was made effective on July 1, 1994. 

Despite this, we sent data used in the proposed rule to Dr. Bruce 

Herbold, USEPA; Dr. Peter Moyle, University of California at Davis; and 

Dr. Larry Brown, U.S. Geological Survey (USGS) for their review. None 

of these reviewers provided written comments concerning the data. 

Additionally, several meetings were held between the Service and CDFG's 

Bay-Delta Division during the comment period to discuss the data and 

methodologies used to establish trends in abundance. The CDFG did not 

disagree with the data used or the methodology used in the analysis.

    As described above, we reopened the comment period twice, once in 

1995 and again in 1998. During the reopened comment period beginning in 

January 1995, we considered a substantive issue that CDFG and others 

raised during the original comment period. The subject of the 

significant scientific disagreement, that resulted in reopening the 

comment period, was whether a resident population of Sacramento 

splittail existed in the upper rivers that was not being detected by 

the current sampling methodologies. The CDFG conducted a study in the 

Fall of 1994 to address this question. The results of the study were 

available in February of 1995 and largely supported our listing. This 

study was conducted by the CDFG under the review of an interagency 

science committee (the Interagency Ecological Program). The re-opening 

of the comment period in 1998 was based, in part, on information in the 

peer-reviewed publication ``Resilience of Splittail in the Sacramento-

San Joaquin Estuary'' (Sommer et al. 1997).

    Moreover, the status report that Meng prepared was peer reviewed 

for its scientific basis. That status report was the basis of an 

article in the Transactions of the American Fisheries Society, which 

was again peer reviewed (Meng L. and P. Moyle, 1995). Additionally, the 

final Sacramento-San Joaquin Delta Native Fishes Recovery Plan (U.S. 

Fish and Wildlife Service 1996) that discussed the status of the 

splittail was subject to public comment and review.

    Although obtaining raw data from various agencies may have been 

delayed due to quality assurance and quality control, all data was 

available between the closing of the first comment period, and during 

both of the reopened comment periods. Although there may be minor 

differences in the final analysis contained in this final rule, these 

differences do not change our conclusion regarding the status of the 

species and the threats to the species.

    Issue 18: The one comment received during the second comment period 

suggests that there may be a resident splittail population upstream of 

the Delta in the upper reaches of the mainstem rivers or their 


    Service Response: We agree that splittail do occur in the upper 

reaches of the Sacramento and San Joaquin rivers in some years. While 

we excluded the beach seine data sets from the analysis of abundance 

(for the reasons stated in our response to Issue 2), we never 

eliminated these, or other data sets, from our analysis of 

distribution. The beach seine sampling collects relatively fewer fish, 

on a catch-per-unit-effort basis, than do the surveys further down the 

Estuary, such as the Chipps Island trawl. This sampling indicates that 

the splittail, although utilizing these upstream areas, are not 

utilizing them in substantial numbers, and certainly not in sufficient 

numbers to constitute a population. The CDFG sponsored a special study 

to try and determine if there were substantial resident populations 

upstream of the Delta in 1994 (Baxter 1994). The results of this study 

indicated that in 1994, the bulk of the population resided in and 

around Suisun Bay, Big Break, and Grizzly Bay, which correlates to the 

distribution of shallow water wetlands throughout this region.

[[Page 5971]]

    Issue 19: Below we summarize comments from several respondents 

concerning the Sommer et al. (1997) paper. The respondents state the 

following reasons for not listing the splittail--(1) The splittail is 

more widely distributed and abundant than previously thought; (2) The 

splittail is a highly fecund, resilient, and long-lived species with 

more than one year class spawning at one time; therefore, it can 

rebound because of its high reproductive capacity; (3) The splittail's 

range has not decreased dramatically; (4) The splittail is able to 

endure drought conditions and rebound in wet years; (5) Splittail are 

robust and can handle stress at the export facilities; and (6) 

Splittail are not at risk from pumping; they are taken in relative 

proportion to their abundance.

    Service Response: Item 1--We disagree with the statement that the 

splittail is more widely distributed and abundant than previously 

thought. However, we have always asserted that in some years splittail 

are found in the upper Sacramento and San Joaquin rivers. During wet 

years, splittail are more widely distributed and may be abundant, due 

to more available spawning habitat. For instance, the wet year of 1995 

enabled splittail to use habitats that are normally unavailable to them 

during normal to dry years. During 1995, the Yolo Bypass provided good 

habitat for spawning splittail and splittail abundance increased. The 

Bypass provided suitable spawning habitat only because it was a wet 

year and the Bypass held water later in the year and for a longer 

duration than is typical. Therefore, when sampling was conducted during 

1995, splittail seemed to be abundant and were found in areas, like the 

Yolo Bypass, that they may not normally be able to use. These managed 

habitats cannot be relied upon during normal or dry years to provide 

spawning habitat unless they are consistently managed for the spawning 

and rearing needs of splittail. During dry years, splittail abundance 

is restricted by the availability of spawning habitat.

    Item 2--We agree that the data demonstrate that splittail are a 

fecund (fertile) species. However, even fecund species can become low 

in abundance due to poor habitat conditions for spawning, which may 

occur during normal or dry years. Young-of-the-year and juvenile 

survivability recruitment is important to the splittail's recovery. 

Even though splittail spawn several thousand eggs, not all will reach 

adulthood. Splittail need good habitat for survivability to spawning 


    Long-lived is a relative term. Compared to an annual species such 

as the delta smelt, splittail, which live for an average of 5 to 10 

years, are long-lived. However, if compared to the green sturgeon, 

which lives to 20 to 40 years of age, the splittail has a short life 


    The term resilience is also a relative term. Due to the larger body 

size, splittail may be more resilient than delta smelt to entrainment 

or impingement, for example, but they are less resilient than larger 

fish such as salmon. We agree with the statement that more than one 

year class of splittail may spawn at one time. However, spawning is not 

always successful. Spawning success is correlated with several factors, 

including wet years, high Delta outflow, and the presence of flooded 

vegetation. If these parameters are not present, then the splittail may 

have low recruitment to the population during that year or years.

    Item 3--We disagree with the statement that the splittail range has 

not decreased dramatically. Historically, splittail were found as far 

north as Redding on the Sacramento River (at the Battle Creek Fish 

Hatchery in Shasta County), as far south as the present-day site of 

Friant Dam on the San Joaquin River, and up the tributaries of the 

Sacramento River as far as the current Oroville Dam site on the Feather 

River and Folsom Dam site on the American River. Splittail were 

captured in southern San Francisco Bay and at the mouth of Coyote Creek 

in Santa Clara County, but they are no longer present there. The 

species is, for the most part, now confined to the Delta, Suisun Bay, 

Suisun Marsh, and the Napa River, reflecting a significant decrease in 

their historical range. Splittail are able to use the Sutter and Yolo 

bypasses only in wet years. In addition, these bypasses are managed 


    Item 4--We disagree with the statement that splittail are able to 

endure drought conditions and rebound in wet years. The years 1987 

through 1992 were consecutive dry years and demonstrated low abundance 

indices for splittail. During dry years, splittail abundance is 

restricted by the availability of spawning habitat. However, 1993 was 

an above normal water year and splittail abundance indices remained 

low. During 1993, after the end of the dry and critically dry years of 

1987 through 1992, water was diverted to fill up the reservoirs that 

had been depleted during the drought. Therefore, even though 1993 was 

an above normal year, the additional water was unavailable for the fish 

to use.

    During the wet years of 1982, 1983, 1986, and 1995, splittail 

abundance indices were high for all age classes, as sampled in the fall 

mid-water trawl. During the wet years of 1984, 1996, and 1997, 

splittail indices were low. Therefore, if wet or above normal year 

types were the controlling factor, essential habitat for splittail 

would have been provided and splittail numbers should have been higher 

in 1984, 1996, and 1997. These data show that splittail do not 

necessarily have high abundance indices during all wet years. Even 

though 1984, 1996, and 1997 were wet years, they may not have had the 

appropriate hydrology, water quality, etc., to support a large spawning 

class. The timing and magnitude of flow events are likely significant 

parameters affecting splittail spawning success. Spring flows also have 

to be of adequate duration and timing to provide the fish with flooded 

vegetation for escape cover, foraging areas, etc. Weather patterns are 

too unpredictable to rely on wet years for the recovery of splittail; 

extended periods of drought would result in low reproduction and 

population declines. (Also see the response to Issue 6).

    Item 5--We agree that splittail are a robust fish. They can obtain 

a size of over 40 cm total length. However, even though they are a 

relatively large fish, they are still subject to stress at the water 

export facilities. Eggs and larvae are still subject to entrainment and 

impingement at the facilities. The largest losses at the pumping plants 

occur in wet years when up to millions of splittail young are lost 

during the spring months. Although splittail salvage better than the 

delta smelt, which cannot be salvaged at all, recent problems at the 

export facilities have reduced the salvage of all fish. New species 

such as the exotic mitten crab have recently posed problems at the 

export facilities. Salvage of fish was requested to be stopped until 

the crab problem can be resolved.

    Item 6--We disagree with the comment that splittail are not at risk 

from pumping and that they are taken in proportion to their relative 

abundance. Although it may appear that splittail are able to handle the 

stress of salvage at the export facilities, they may not necessarily 

survive after release. Better studies are needed to determine the 

extent of latent mortality.

    Splittail are more likely to be at risk during pumping, depending 

on the water year and where the fish are distributed during spawning. 

During dry years, splittail are concentrated in the few areas that have 

flooded vegetation that can support spawning. Therefore,

[[Page 5972]]

most of the population may be concentrated in one part of the Delta, 

potentially resulting in more take at the pumps in proportion to the 

amount of fish in the system. Conversely, more splittail are taken at 

the pumps during wet years because there is more habitat available for 

spawning, which may result in more recruitment to that year class. 

Depending on the distribution of spawning, fish may be taken in 

disproportion to their overall abundance.

    Issue 20: Several respondents stated that programs and agreements 

like the Bay/Delta Accord, CALFED (a consortium of State and Federal 

agencies convened to address water issues in California), and VAMP will 

result in recovery of splittail. Therefore, there is no need to list 

the species.

    Service Response: We agree that the threats associated with the 

degradation of the Delta may be lessened by the successful 

implementation of the Bay/Delta Accord, CALFED, Central valley Project 

Improvement Act (CVPIA), and VAMP. However, to date, the results of 

these agreements and programs have not been quantified due to 

subsequent wet years that did not require regulatory intervention for 

delivery of water for fish species. At this time, it cannot be 

determined whether these actions have been implemented to an extent 

that will prevent the splittail from becoming endangered within the 

foreseeable future.

    Issue 21: A respondent stated that we failed to comply with the 

Regulatory Flexibility Act and Executive Order 12630.

    Service Response: The Endangered Species Act requires that listing 

decisions be made solely on the basis of biological information. The 

legislative history to the Endangered Species Act amendments of 1982 


    ``The Committee of Conference * * * adopted the House language 

which requires the Secretary to base determinations regarding the 

listing or delisting of species `solely' on the basis of the best 

scientific and commercial data available to him. As noted in the House 

Report, economic considerations have no relevance to determinations 

regarding the status of species and the economic analysis requirements 

of Executive Order 12291, and such statutes as the Regulatory 

Flexibility Act and the Paperwork Reduction Act, will not apply to any 

phase of the listing process.'' (H.R. Conf. Rep. No. 567, 97th Cong., 

2d Sess. 12, 19-20 (1982); S. Rep. No. 418, 97th Cong., 2d Sess. 4 


    In consultation with our Solicitor's Office, we have concluded that 

the analyses required by the Regulatory Flexibility Act are not 

applicable to listing determinations.

    Regarding Executive Order 12630, Governmental Actions and 

Interference with Constitutionally Protected Property Rights, the 

Attorney General has issued guidelines to the Department of Interior 

(DOI) on implementation of this Executive Order. Under these 

guidelines, a special rule applies when an agency within the DOI is 

required by law to act without exercising its usual discretion--that 

is, to act solely upon specified criteria that leave the agency no 


    In this rulemaking context, we might be subject to legal challenge 

if we considered or acted upon economic data. In these cases, the 

Attorney General's guidelines state that Takings Implications 

Assessments (TIAs) shall be prepared after, rather than before, the 

agency makes the decision upon which its discretion is restricted. The 

purpose of TIAs in these special circumstances is to inform policy 

makers of areas where unavoidable fifth amendment taking exposures 

might exist. Such TIAs shall not be considered in the making of 

administrative decisions that must, by law, be made without regard to 

their economic impact.

    As described above, Congress required us to list species based 

solely upon scientific and commercial data indicating whether or not 

they are in danger of extinction. The Act does not allow us to withhold 

a listing based on concerns regarding economic impact. The provisions 

of the guidelines relating to nondiscretionary actions clearly are 

applicable to the determination of threatened status for the Sacramento 


Summary of Factors Affecting the Species

    After thorough review and consideration of all the best scientific 

and commercial information available, we have determined that the 

Sacramento splittail should be classified as a threatened species. 

Procedures found at section 4 of the Act and regulations implementing 

the listing provisions of the Act (50 CFR part 424) were followed. A 

species may be determined to be endangered or threatened because of one 

or more of the five factors described in section 4(a)(1). These factors 

and their application to the Sacramento splittail (Pogonichthys 

macrolepidotus) are as follows:

    A. The present or threatened destruction, modification, or 

curtailment of its habitat or range. The Sacramento splittail, once 

widely distributed in the Central Valley of California from Redding to 

the modern-day site of Friant Dam near Fresno, is now primarily 

restricted to the Estuary due to dams, diversions, dredging, and the 

diking and filling of historic flood basins. Within this constricted 

range, splittail have declined by about 62 percent since 1984. However, 

overall percentage decline over its historical range is much greater. 

Populations have fluctuated somewhat in the past, with most recruitment 

taking place in wet years. In wet years since 1978, however, splittail 

recruitment has declined consistently with catch-per-unit-effort of 

12.3, 8.1, 2.0, 1.3, and 0.3 for 1978, 1982, 1983, 1986, and 1993, 

respectively. The updated data from CDFG demonstrate the same decline 

by wet years, with 37.3, 15.5, 8.9, 7.3, and 0.6 in 1993. Other wet 

year data include 1995, 1996, and 1997. These indices are 44.5, 2.1, 

and 2.6, respectively. However, as stated before, 1995 was a very wet 

year and there was suitable spawning habitat for splittail in the 

Estuary. The 1995 data point does not represent a reversal in the 

decline of the species. Splittail declines are highest (82 percent/83 

percent with updated data) in the shallow water Suisun Bay area, the 

center of its distribution. Therefore, as stated above, wet years are 

not always indicative of high abundance indices. However, the current 

data do not indicate a change in this trend.

    Delta water diversions and exports currently total about 9 million 

acre-feet per year, but plans now being prepared could increase exports 

and diversions in the future. The Federal and State water projects 

presently export about 6 million acre-feet per year from the Delta when 

sufficient water is available, and in-Delta agricultural uses result in 

diversion of about 3 million additional acre-feet per year. We know of 

21 major Central Valley Project, State Water Project, or private 

organization proposals that would result in increased water exports 

from the Delta, reduced water inflow to the Delta, changes in timing 

and volume of Delta inflow, or increases in heavy metal contamination 

of the Delta. These proposed projects or actions include but are not 

limited to revisions to the Central Valley Project Operations Criteria 

and Plan, Los Banos Grandes Reservoir, Los Vaqueros Reservoir, South 

Delta Water Management Program, North Delta Water Management Project, 

West Delta Water Management Project, Delta Wetlands Corporation Water 

Storage Project, Folsom Dam Reoperation, Oroville Dam Reoperation, 

Auburn Dam, Central Valley Project contract renewals and amendments 

such as those on the American River that include the

[[Page 5973]]

Sacramento County water contracts, East Bay Municipal Utilities 

District water contract, as well as other increases in diversions 

resulting from the American River Water Forum process. Other water 

contracts renewals include the Solano County Water District. Contra 

Costa Water District is currently proposing to increase their 

diversions for future water supply. The Central Valley Project and 

State Water Project wheeling purchase agreement, reactivation of the 

San Luis Drain, Stanislaus-Calaveras River Basin Water Use Program, 

Suisun Marsh Project Phase Three and Four, Federal Water Project change 

in diversion point, and State Water Project Pump additions. All of 

these projects would impact the habitat of the splittail.

    Changes in water diversions are most likely at the State Water 

Project. For the most part, the Federal pumping plant has operated at 

capacity for many years (pumping at rates up to 4,600 cubic feet per 

second (cfs)), so increased exports at this plant are unlikely. 

However, the State Water Project pumping plant and capacity of the 

State Aqueduct have considerable unused capacity. The State Water 

Project currently pumps at rates up to 6,400 cfs and plans to increase 

pumping rates by more than 50 percent. Local private diverters are 

relatively stable and export up to 5,000 cfs from about 1,800 

diversions scattered throughout the Delta. The DWR (1992) reported past 

and projected State Water Project deliveries from Delta sources during 

the years of 1962 to 2035. In the 1980s, deliveries ranged from 1.5 

million acre-feet to 2.8 million acre-feet. By 2010, deliveries of up 

to 4.2 million acre-feet are planned.

    Since 1983, the proportion of water exported from the Delta during 

October through March has been higher than in earlier years (Moyle et 

al. 1992). Changes in timing and amounts of exports affect fish 

migration and spawning habits, as well as operations of upstream water 

storage facilities. Dampening of peak spring flows by springtime 

diversions to storage facilities to replenish depleted reservoirs has 

deleterious effects on estuarine species such as the splittail, which 

have evolved in a system with periodic spring flooding.

    Federal and State water diversion projects in the southern Delta 

export, by absolute volume, mostly Sacramento River water with some San 

Joaquin River water. During periods of high export pumping and low to 

moderate river flows, reaches of the San Joaquin River reverse 

direction and flow upstream to the pumping plants located in the 

southern Delta. When total diversion rates are high relative to Delta 

outflow, the lower San Joaquin River and other channels have a net 

upstream (i.e., reverse or negative) flow. Out-migrating larval and 

juvenile fish of many species become disoriented due to reverse flows. 

Fish, including Sacramento splittail, delta smelt, longfin smelt 

(Spirinchus thaleichthys), and all runs of salmon and steelhead are 

lost at pumps and to predation at various water facilities and other 

diversion sites. Because data from State and Federal pumping facilities 

indicate that splittail migrate upstream to spawn, positive outflows 

are also important to transport splittail young downstream (Meng 1993).

    In recent years, the number of days of reversed San Joaquin River 

flow have increased (Moyle et al. 1992), particularly during the 

February-June spawning months for splittail. Reverse flows in the San 

Joaquin River may transport more splittail young towards pumping 

facilities in the south Delta where the splittail are entrained by 

pumps and diversions. The survival rate of splittail salvaged from 

entrainment is unknown. However, salvage operations have been shown to 

result in 50 percent losses of salvaged fish (Scott Barrow, DFG, pers. 

comm. 1995) (see factors C and E of this section for more discussion 

about entrainment and salvage).

    With full implementation of the WQCP for the Sacramento-San Joaquin 

Estuary (described below) we anticipate an overall reduction of the 

number of days of reverse flow in the lower San Joaquin River during 

the spring period. Pumping will shift from the spring period to later 

in the year. This pumping will likely have to be supported by reservoir 

withdrawals. Reservoir releases in the spring may not be as frequent 

depending on how much space is available in the reservoirs carried over 

from the previous year. Increasing demand will also require more 

support from reservoirs for export, which will alter the flow patterns. 

Changes in reservoir operations and ramping rates for flood control may 

affect shallow water spawning habitat along river corridors and 

exacerbate stranding of splittail.

    Estuaries are ecosystems where the mixing zone and salinity levels 

are determined by interaction of river outflow and tidal action. 

Splittail are most abundant in the shallow water of Suisun Bay, which 

is historically associated with the entrapment zone. The young of this 

species require high zooplankton densities, which are common in the 

entrapment zone. Production of zooplankton increases when the 

entrapment zone occupies a large geographic area with extensive shoal 

regions within the euphotic zone (depths less than 4 meters), such as 

Suisun and Grizzly bays. Fall mid-water trawl survey data collected by 

CDFG indicate that 72 percent of the splittail captured from 1967 to 

1992 in the Estuary were taken in the shallow water areas of Suisun and 

Grizzly bays (Meng 1993).

    During periods of drought and increased water diversions, the 

entrapment zone and associated fish populations are shifted farther 

upstream in the Estuary. During years prior to 1984, the entrapment 

zone was located in Suisun Bay from October through March (except in 

months with exceptionally high outflows or during years of extreme 

drought). From April through September, the entrapment zone usually was 

located upstream in the river channels. Since 1984, with the exception 

of the record 1986 flood outflows, the entrapment zone has been located 

primarily in the river channels during the entire year because of 

drought and increased water exports and diversions. When located 

upstream, the entrapment zone is confined to deep river channels where 

the total surface area is smaller, fewer shoal areas exist, water 

currents are swifter and more turbulent, and zooplankton productivity 

is low. In all respects, the upstream river channels are much less 

favorable for rearing of splittail. Splittail declines since 1984 have 

been concurrent with an increasing amount and proportion of freshwater 

diversions that confine the mixing zone to narrow, deep, and less 

productive channels in the lower rivers.

    Recent research indicates that splittail will use the Yolo and 

Sutter bypasses during the winter and spring months for foraging and 

spawning (Sommer et al. 1997). The bypasses are two extensive 

floodplain areas used for flood control, agriculture, and wildlife 

habitat. The bypasses serve as a control outlet for the Sacramento 

River, which historically flooded large areas of the adjacent valley 

during high water events in the winter and spring. The water from the 

Sacramento River is diverted to the bypasses through a passive system 

of weirs. Water enters the Yolo Bypass from the Sacramento River via 

the Fremont and Sacramento Weirs. The Sutter Bypass is inundated 

through the Tisdale Weir.

    In 1995, the bypasses provided good habitat for fish, particularly 

splittail because it was an extremely wet year and the bypasses were 

flooded for several weeks in March and April. However, the bypasses do 

not get flooded at all in dry and critically dry years. Therefore, 

during those years,

[[Page 5974]]

when splittail would need the habitat the most, it is not provided by 

the bypasses.

    The Yolo Bypass is inundated whenever the Sacramento River stage at 

Fremont Weir exceeds 33.5 feet. About 3/4 of the years going back to 

the mid-1930s have had overflows into the Yolo Bypass. Even though the 

water was high enough to overtop the Fremont Weir, the water may not 

have stayed on the Bypass consistently nor long enough to benefit 


    Under current water management practices, the bypasses cannot be 

relied upon throughout any given spawning season to provide habitat for 

splittail. As mentioned above, water is placed onto the bypasses by 

overtopping of weirs along the Sacramento River. The flooding of the 

bypasses is sporadic at best. The volume of water varies from year to 

year as well as does the time of year when the bypasses are inundated. 

The water may be placed intermittently on the bypasses, depending on 

how much rainfall occurs at any given time. For instance, water has 

been placed onto the Yolo Bypass as early as December and has remained 

on the Bypass as late as May. Water has also been placed on the Bypass 

for a short time and drained off. The water could be drained off at 

some point during the season and then with more heavy rainfall, the 

bypasses could become flooded again. Therefore, these systems would not 

provide suitable spawning habitat consistently for splittail. Also, the 

bypasses do not drain at consistent levels. There are pockets and holes 

that form which may trap and strand fish as the water drains. During 

some years, the bypasses do not have enough water or retain water long 

enough to allow fish to enter the bypasses, spawn, and then grow to a 

size that will allow them to out-migrate. The artificial systems of the 

Yolo and Sutter bypasses, as currently managed, cannot be relied upon 

to recover the splittail. The bypasses provide accessible and suitable 

splittail spawning habitat only during wet years where the water 

consistently remains on the bypasses for an extended period of time, as 

in 1995.

    B. Overutilization for commercial, recreational, scientific, or 

educational purposes. Overutilization is not known to be a factor 

affecting this species. Some scientific collecting is conducted for 

splittail but these activities do not adversely affect this species. 

Striped bass anglers report occasional use of splittail as bait, but 

this usage is thought to have little effect on the species. A small 

fishery for splittail used to exist in the Sacramento River (Daniels 

and Moyle 1983, Caywood 1974). However, no recent records of splittail 

harvest exist, probably because little or no harvest now occurs due to 

its declines. Records of splittail harvest are also sketchy because 

identification of this species is often confused with other nongame 

species. No other recreational or educational uses of this species 

exist that may affect its abundance.

    C. Disease or predation. Predation is thought to be a relatively 

minor factor affecting the Sacramento splittail, especially compared to 

the other factors discussed in this final rule. Striped bass and other 

predatory fish are attracted to concentrated prey at fish salvage 

release sites, such as occur at Clifton Court Forebay. The salvaged 

fish, including splittail, are collected from holding wells of the 

salvage facilities, placed in the salvage trucks, transported to the 

release sites, and deposited in bulk from a pipe running from the truck 

to a near-shore area, thus resulting in predator attraction. Fifty 

percent of the released fish are lost (Scott Barrow, CDFG, pers. comm. 

1995). These losses are largely due to attraction of predatory fish to 

the release site of the salvage operations. Splittail and striped bass, 

however, coexisted for decades in the Estuary and recent declines in 

splittail have occurred in conjunction with striped bass population 

declines. Increases in striped bass populations could threaten reduced 

numbers of splittail. Recently, the CDFG has foregone striped bass 

stocking or modified their striped bass management because of potential 

harm to federally listed Sacramento River winter-run chinook salmon and 

delta smelt.

    Susceptibility to disease, due to poor water quality, may be a 

factor in the decline of splittail. Workers at State and Federal water 

project facilities in the south Delta have reported high incidences of 

adult splittail in poor health. The south Delta is dominated by San 

Joaquin River flow, a large part of which is made up of agricultural 

drainage. Pesticides (e.g., chlorpyrifos, carbofuran, and diazinon), 

salts (e.g., sulfates, selenium), and total dissolved solids from this 

drainage are concentrated by reverse San Joaquin River flows and result 

in poor water quality (Dennis Westcot, Central Valley Regional Water 

Quality Control Board, pers. comm.).

    D. The inadequacy of existing regulatory mechanisms. Regulatory 

mechanisms currently in effect do not adequately protect the splittail 

or its habitat. This species is not listed by the State of California.

    We are analyzing the potential effects on splittail and other fish 

and wildlife resources in California as a result of enactment of the 

CVPIA (Pub. L. 102-575) under the National Environmental Policy Act 

(NEPA) and the Programmatic Environmental Impact Statement currently 

under development. The CVPIA may benefit the splittail, but does not 

adequately protect the species at this time. Two of the stated purposes 

of the CVPIA are to ``protect, restore, and enhance fish, wildlife, and 

associated habitats in the Central Valley and Trinity River basins of 

California'' and ``to contribute to the State of California's interim 

and long term efforts to protect the San Francisco Bay-Sacramento-San 

Joaquin Delta Estuary.'' Section 3406(b)(2) dedicates 800,000 acre-feet 

of Central Valley Project yield annually to implement fish, wildlife, 

and habitat restoration, and to help federally listed species. The 

800,000 acre-feet identified in the CVPIA may be used to meet the DOI's 

obligations under the Bay-Delta Accord (discussed below). The rest of 

the water can be used for instream flows, additional Delta outflow, and 

the other purposes of the CVPIA. Because of the multiple purposes of 

the CVPIA, flows may be provided at times of the year that may not 

benefit splittail, such as spawning flows in the fall for salmon. 

Additionally, because of the need to balance these flows for all uses 

under the CVPIA, certain spring flows may be less than what is fully 

needed for spring spawning of splittail. We anticipate that splittail 

will benefit from implementation of the CVPIA, although the magnitude 

and timeliness of these protections may be inadequate to prevent 

further decline of splittail. On November 20, 1997, the DOI announced 

its decision regarding use of the 800,000 acre-feet of water identified 

in the CVPIA. The decision is to be implemented for the next 5 years 

and involves not only upstream actions but also actions in the Delta 

which may benefit splittail. However, since the Central Valley Project 

represents only a portion of the water development projects in the 

Central Valley, the CVPIA is likely insufficient to fully protect 

splittail at this time.

    Protective measures currently being implemented to benefit the 

delta smelt may benefit the splittail, such as restrictions on pumping 

under certain conditions. However, the ecological requirements of these 

species differ, especially with respect to timing of important 

development stages and habitat uses. Unlike delta smelt, splittail 

require flooded lowland habitat for spawning and are particularly 

vulnerable to disturbance or destruction of marshy habitat.

[[Page 5975]]

    The Suisun Bay area, including Suisun Marsh, is the best known 

habitat for splittail, but this habitat has been adversely altered by 

higher salinities in the spring. These higher salinities are caused by 

operations of reservoirs that divert water to storage as well as 

exports from the Delta that allow seawater to intrude farther upstream 

in Suisun Marsh. Prior to the Bay-Delta Accord/WQCP, there were 

relatively few periods when freshwater outflows of any significance 

were mandated to be released through the Delta and Suisun Bay for 

wildlife or fisheries. State and Federal agencies had planned to 

increase 1991 and 1992 water supplies for out-of-stream uses at the 

expense of environmental protection of estuarine fish and wildlife 

resources in the fifth and potentially sixth years of drought (Morat 

1991). Because of significantly higher than normal precipitation and 

subsequent higher instream flows after March 1991, a State agency 

request for relaxation of Delta water quality standards was withdrawn.

    Subsequently, on December 15, 1994, the Federal government, the 

State of California, and urban, agricultural and environmental 

interests agreed to the Principles for Agreement on a comprehensive, 

coordinated package of actions designed to provide interim protection 

to the San Francisco Bay and Sacramento-San Joaquin River Delta 

Estuary. That agreement is referred to as the 1994 Bay-Delta Accord 

(Accord). The Accord was recently extended to December 15, 1999. The 

Accord established parameters to protect the beneficial uses of the 

Bay-Delta Estuary. Among these beneficial uses are objectives to ensure 

adequate Delta outflow for the maintenance of suitable habitat for 

various life stages of aquatic organisms and objectives for export 

limits to protect the habitat of estuarine-dependent species and reduce 

their entrainment at the major export pumps in the southern Delta.

    The X2 standard provides outflows to maintain low salinity (2 parts 

per thousand) habitat at three distinct areas in the Bay-Delta: 1) the 

confluence of the Sacramento and San Joaquin rivers, 2) Chipps Island, 

and 3) Roe Island. Compliance of this standard will provide variability 

for aquatic organisms and aid in their recovery. The E/I ratio 

establishes a combined export rate (Clifton Court Forebay inflow plus 

export at the Tracy Pumping Plant) based on the best available estimate 

of the Eight River Index. When the estimate of the Eight River Index is 

ultimately made, the export facilities may then pump a set percentage 

of Delta inflow. Although these parameters will likely protect fish and 

wildlife, they have not been adequately tested over the past 4 years 

due to the extreme wet conditions.

    Present regulatory processes do not ensure that water inflows to 

Suisun Bay and the western Estuary will be adequate to maintain the 

mixing zone near or in Suisun Bay to benefit splittail. The SWRCB has 

the authority to condition or require changes in the amount of water 

inflow and the amount of water exported or diverted from the Delta. In 

testimony given before the SWRCB's Water Quality/Water Rights Hearings 

in 1987, one of our biologists expressed concern for several Delta 

species, including splittail (Lorentzen 1987). The SWRCB did not take 

regulatory or legal action to protect this fish or its habitat during 

the following 4 years. On May 1, 1991, the SWRCB adopted the WQCP for 

Salinity for the San Francisco Bay-Sacramento-San Joaquin Delta Estuary 

(1991 Bay/Delta Plan). On September 3, 1991, under provisions of the 

Clean Water Act, the USEPA disapproved certain water quality standards 

due to the SWRCB's failure to adopt criteria to protect estuarine 

habitat. In April 1992, the Governor of California announced a new 

water policy that included a directive to the SWRCB to establish 

``interim measures'' to reverse the decline of fishes in the Bay and 

Delta. Accordingly, the SWRCB released an interim water quality plan 

(Draft Decision 1630) in December 1992 that immediately was suspended 

by the Governor. In 1993, the USEPA began the process of forming 

replacement standards for those portions of the 1991 Bay/Delta Plan 

that were disapproved.

    Before USEPA's final rule on Water Quality Standards for Surface 

Waters of the Sacramento River, San Joaquin River, and San Francisco 

Bay and Delta became effective on December 14, 1994, and as a result of 

Bay-Delta Accord that was signed on December 15, 1994, the SWRCB issued 

and adopted Water Rights Order 95-6. The protections contained in this 

Water Rights Order were determined to be roughly equivalent to the 

protections in USEPA's final rule on water quality standards, and 

USEPA's rule was withdrawn. Although the SWRCB has issued a draft 

Environmental Impact Report (EIR), no long term implementation plan has 

been developed or actually implemented for the new water quality plan. 

Substantial opposition exists to certain implementation measures 

identified in EIR. Institutional guarantees of compliance have been 

lacking in the past and are needed in the future before existing 

mechanisms can contribute to protection of this species. Records show 

that the previous salinity standards contained in the SWRCB's Water 

Rights Decision 1485 were inconsistently implemented and frequently 


    Among other things, the Bay-Delta Accord was intended to provide 

for increased flexibility in the water project operations to respond to 

ecological needs. Appropriate use of this increased flexibility may 

have demonstrated that the established regulatory mechanisms were 

sufficient to protect splittail. However, even though splittail were 

proposed for listing before the Bay-Delta Accord was signed, water 

project operations have rarely been changed to provide protection for 

splittail. In 1995, for example, a wet year that afforded opportunities 

to significantly reverse the decline of splittail while maintaining 

water supply, more than 6.3 million juvenile splittail were entrained 

at the CVP and SWP facilities in 2 months from late April to late June. 

Of these fish, at least 50 percent were lost due to transport and 

release. Predation in Clifton Court Forebay, inefficiency in screening 

fish from diversion facilities, and handling most likely increased this 

percentage. Despite the availability of the mechanism for increased 

flexibility in project operations provided by the Bay-Delta Accord, 

operations of the CVP and SWP were changed for only one 3-day period in 

late June of 1995 to minimize entrainment of splittail. Thus, an 

opportunity to significantly increase abundance and distribution of 

splittail, and the opportunity to reverse the decline of the species 

was lost.

    As a direct result of a Framework Agreement, the Federal and State 

governments established the CALFED Bay-Delta Program (Program). This 

Program is a cooperative effort of the DOI, the U.S. Department of 

Commerce, the USEPA, the California Environmental Protection Agency, 

and the California Resources Agency, with the involved public formally 

participating through the Bay-Delta Advisory Council. The mission of 

the Program is to develop a long term comprehensive plan that will 

restore ecological health and improve water management for all 

beneficial uses of the Bay-Delta system. The plan will specifically 

address fish and wildlife protection, water supply reliability, levee 

stability, and water quality issues in the Delta. We are an active 

participant in the Program and we believe that the eventual 

implementation of the plan will contribute to the protection and 

recovery of the Sacramento splittail. However, the plan is not yet 


[[Page 5976]]

we cannot evaluate specific conservation measures until they have been 

identified, described, and committed to in an approved final plan.

    As a result of the Bay-Delta Accord, a program was established to 

implement non-flow related actions to benefit fish and wildlife 

resources. This program is known as Category III. The Category III 

program is funded by Federal, State, and non-governmental organizations 

and was funded with $60 million annually for the first 3 years of the 

Bay-Delta Accord. There was approximately $10 million dollars funded in 

the first year by the Metropolitan Water District (MWD). The MWD 

contributed the same amount in the second year, with approximately $2-4 

million contributed by other water districts and agencies. In November 

1996, California voters passed Proposition 204, which provided State 

funds for the Category III activities as well as other CALFED 

activities. In 1997 the Federal government passed an $85 million 

appropriation for Category III activities and CALFED functions. In the 

Fall of 1997, CALFED awarded $60.6 million dollars toward proposals 

under the Category III program. Some of these proposals will benefit 

splittail through habitat enhancement or restoration. Some of these 

projects have been implemented. However, due to the time frame required 

to see if the project has met its objective, that is, to provide 

suitable spawning habitat for splittail, we cannot determine if these 

projects will be successful. However, because Category III projects are 

not intended to enhance flow conditions in the Delta or its 

tributaries, it cannot provide needed flows.

    E. Other natural or manmade factors affecting its continued 

existence. Splittail are vulnerable to natural events, such as drought, 

because of the consistent decline in population indices and severely 

constricted range and distribution. Drought will reduce the available 

spawning area for the splittail because of reduced instream flows. 

Because the range is already restricted and the population has 

declined, a prolonged natural event such as drought (compounded by 

exports and diversions described in Factor A) could endanger the 


    Unscreened or inefficiently screened municipal, agricultural, and 

industrial water diversions and other water facilities are a 

significant problem for the splittail. It is estimated that there are 

currently over 1800 unscreened diversions in the Delta. Screens are 

currently designed for striped bass and salmonids. Approach velocities 

and mesh sizes are therefore not appropriate for splittail. Behavioral 

barriers (louver screens) at the State and Federal salvage facilities 

that were designed using striped bass and salmonid criteria, also are 

not appropriate for splittail. Release sites for salvaged fish attract 

predators, likely resulting in low survivorship overall (Lloyd Hess, 

BOR, pers. comm. 1995). Also, it is likely that few young survive 

salvaging at the Federal and State pumping plants because juveniles of 

most fish species are more delicate than adults.

    Poor water quality also may adversely affect splittail, through 

direct exposure to toxins, which increases vulnerability to disease as 

described above in Factor C, and depletion of zooplankton and 

invertebrate food sources. All major rivers that are tributary to the 

Estuary are exposed to large volumes of agricultural and industrial 

chemicals that are applied in the Central Valley watershed (Nichols et 

al. 1986). Agricultural chemicals and their residues, as well as 

chemicals originating in urban runoff, find their way into the rivers 

and Estuary. Approximately 10 percent of the total pesticide use in the 

United States occurs in the Sacramento and San Joaquin River watersheds 

(Kuivila and Foe 1995). Recently, high concentrations of 

organophosphate and carbamate pesticides from agricultural uses have 

been documented entering the Estuary. These pesticides are acutely and 

chronically toxic to zooplankton and fishes as far west as Martinez in 

Suisun Bay and as far south as Vernalis on the San Joaquin River (Foe 

1995, Bailey et al. unknown date). The periods of pesticide use 

coincide with the timing of migration, spawning, and early development 

of splittail. During rainfall runoff events, acutely toxic pulses of 

pesticides move down the rivers and through the Estuary with remarkable 

persistence and relatively little dilution (Kuivila and Foe 1995).

    Toxicology studies of rice field irrigation drain water of the 

Colusa Basin Drainage Canal have documented significant toxicity of 

drain water to striped bass embryos and larvae, Oryzias latipes larvae 

(in the Cyprinodontidae family), and opossum shrimp, which is the major 

food organism of striped bass larvae and juveniles (Bailey et al. 

1991), as well as all age classes of splittail. This drainage canal 

flows into the Sacramento River just north of the City of Sacramento. 

The majority of drain water samples collected during April and May 1990 

were acutely toxic to striped bass larvae (96-hour exposures); this was 

the third consecutive year rice irrigation drain water from the Colusa 

Basin was acutely toxic (Bailey et al. 1991). Splittail may be 

similarly affected by agricultural and industrial chemical runoff, 

particularly because, like striped bass, adults migrate upriver to 

spawn and young rear upriver until waters recede in late spring.

    Some heavy metal contaminants have been released into the Estuary 

from industrial, urban, and mining enterprises. While the effects of 

these contaminating compounds on splittail larvae and their zooplankton 

food resources are not well known, the compounds could adversely affect 

survival. In addition, increases in urban development in the Sacramento 

Valley will continue to result in concurrent increases in urban runoff. 

Selenium has been found in aquatic organisms (Saiki and Lowe 1987, 

Henderson et al. 1995) and fish species in the San Joaquin River 

watershed (Nakamoto and Hassler 1992). Selenium has been shown to cause 

reproductive failure, developmental defects, and mortality of fish 

species (Hermanutz 1992, Skorupa et al. 1996).

    In recent years, untreated discharges of ship ballast water has 

introduced exotic aquatic species to the Estuary ecosystem (Carlton et 

al. 1990). Several exotic species may adversely affect the splittail. 

An Asian clam (Potamocorbula amurensis), introduced as veliger larvae 

in 1986, was first discovered in Suisun Bay during October 1986. By 

June 1987, the Asian clam was widespread in Suisun, San Pablo, and San 

Francisco bays irrespective of salinity, water depth, and sediment type 

at densities greater than 10,000 individuals per square meter. Asian 

clam densities declined to 4,000 individuals per square meter as the 

population aged during the year (Carlton et al. 1990). Persistently low 

river outflow and concomitant elevated salinity levels may have 

contributed to this species' population explosion (Carlton et al. 

1990). The Asian clam could potentially play an important role in 

affecting the phytoplankton dynamics in the Estuary. The clam may have 

an effect on higher trophic levels by decreasing phytoplankton biomass.

    The Chinese mitten crab (Eriocheir sinensis), has also been 

recently introduced to the Delta, either by deliberate release to 

establish a fishery or through accidental release via ballast water. 

The Chinese mitten crab has interfered with the ability to effectively 

salvage fish at the export facilities by clogging the internal piping.

    Historically, Eurytemora affinis, the native euryhaline copepod, 

has been the most important food for larval fishes in the Estuary. 

Three non-native species of euryhaline copepods (Sinocalanus

[[Page 5977]]

doerrii, Pseudodiaptomus forbesi, and P. marinus) became established in 

the Delta between 1978 and 1987 (Carlton et al. 1990), while E. affinis 

populations have declined since 1980. It is not known if the exotic 

species have displaced E. affinis or whether changes in the estuarine 

ecosystem now favor S. doerrii and the two Pseudodiaptomus species 

(Moyle et al. 1989). Sinocalanus doerrii is difficult for larval fishes 

to catch because of its fast swimming and effective escape response 

(Meng and Orsi 1991). Reduced feeding efficiency and ingestion rates 

weaken and slow the growth of splittail young and make them more 

vulnerable to starvation or predation.

    We have carefully assessed the best scientific and commercial 

information available regarding past, present, and future threats faced 

by this species in this listing determination. Sacramento splittail 

have declined by 62 percent over the last 15 years. This species has 

been effectively extirpated from the majority of its range and is now 

vulnerable to numerous threats in the Estuary as discussed above. 

Because Sacramento splittail are long-lived, their decline has been 

gradual, and extinction is not imminent, listing the splittail as 

endangered would not be appropriate. Although this species is not in 

imminent danger of extinction, it is likely to become endangered in the 

foreseeable future if present threats and current population trends 

continue. Therefore, based on the evaluation of all available 

information on abundance, present distribution, and threats to this 

species, we have determined that listing the Sacramento splittail as 

threatened is appropriate at this time. Critical habitat is not 

designated for reasons discussed in the ``Critical Habitat'' section of 

this rule.

Critical Habitat

    Critical habitat is defined in section 3 of the Act as--(i) the 

specific areas within the geographical area occupied by a species, at 

the time it is listed in accordance with section 4 of the Act, on which 

are found those physical or biological features (I) essential to the 

conservation of the species and (II) which may require special 

management considerations or protection and; (ii) specific areas 

outside the geographical area occupied by a species at the time it is 

listed, upon determination that such areas are essential for the 

conservation of the species. ``Conservation'' as defined in section 

3(3) of the Act 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 designate critical habitat at the time the species is 

listed. The regulations (50 CFR 424.12(a)(1)) state that designation of 

critical habitat is not prudent when one or both of the following 

situations exist--(1) the species is threatened by taking or other 

human activity, and identification of critical habitat can be expected 

to increase the degree of threat to the species, or (2) such 

designation of critical habitat would not be beneficial to the species. 

We have determined that designation of critical habitat for the 

Sacramento splittail is not prudent.

    Critical habitat receives consideration under section 7 of the Act. 

Section 7(a)(2) requires Federal agencies to consult with the Service 

to ensure that any action they carry out, authorize, or fund does not 

jeopardize the continued existence of a federally listed species or 

destroy or adversely modify designated critical habitat. The Service's 

implementing regulations (50 CFR part 402) define ``jeopardize the 

continuing existence of'' and ``destruction or adverse modification 

of'' in very similar terms. To jeopardize the continuing existence of a 

species means to engage in an action ``that reasonably would be 

expected, directly or indirectly, to reduce appreciably the likelihood 

of both the survival and recovery of a listed species by reducing the 

reproduction, numbers, or distribution of that species.'' Destruction 

or adverse modification of habitat means a ``direct or indirect 

alteration that appreciably diminishes the value of critical habitat 

for both the survival and recovery of a listed species in the wild.'' 

Common to both definitions is an appreciable detrimental effect to both 

the survival and recovery of a listed species.

    For any listed species, an analysis to determine jeopardy under 

section 7(a)(2) would consider impacts to the species resulting from 

impacts to habitat. Therefore, an analysis to determine jeopardy would 

include an analysis closely parallel to or, for the splittail, 

equivalent to an analysis to determine adverse modification of critical 

habitat. For the Sacramento splittail, any modification to suitable 

habitat within the species' range has the potential to affect the 

species. Actions that may affect the habitat of the splittail include, 

but are not limited to--(1) reduction of fresh water flows, (2) 

degradation of water quality, (3) reduction in the quality or quantity 

of flooded vegetation, (4) alteration of shallow water areas containing 

submergent (under water) and/or emergent (above the water surface) 

vegetation, and (5) construction of structures that interfere with 

migration patterns or block free access to spawning or rearing areas. 

Although the splittail is a wide ranging species, actions affecting 

habitat can have relatively large impacts to the population. For 

example, an activity that destroys or degrades, or blocks access to, an 

important spawning site could result in reproductive failure of a 

significant portion of the population affecting population size and age 

structure in following years. For the Sacramento splittail, we have 

determined that, were critical habitat designated, it would include no 

areas that would not be subject to consultation under the jeopardy 

standard. Moreover, we have determined that the level of habitat impact 

necessary to result in a determination of destruction or adverse 

modification of critical habitat (were we to designate critical habitat 

for the splittail) would also result in a determination of jeopardy to 

the species. Therefore, were critical habitat to be designated for the 

splittail, no additional section 7 consultations beyond those caused by 

the listing itself would take place, nor would the practical result of 

any such consultations differ.

    To date, we have prepared 284 conference reports for the Sacramento 

splittail for projects involving changes in hydrology, availability of 

spawning habitat, migratory cues, and other behavioral patterns as well 

as potential increase in entrainment. Three of these conferences 

resulted in initial draft jeopardy determinations. These draft jeopardy 

determinations provide evidence that, by their very nature, impacts to 

splittail habitat that would result in a determination of adverse 

modification would result in a determination of jeopardy to the 

species. For these projects, the habitat impacts were the primary basis 

for the jeopardy determinations.

    The three projects that resulted in initial draft jeopardy 

conference reports included the proposed Delta Wetlands Project (March 

1996) (this project has since been modified to avoid jeopardy), 

proposed modifications to the south Delta Temporary Barrier Program 

(January 1997), and the proposed Interim South Delta Program (April 

1998). The consultations and conferences for these projects addressed 

the adverse effects on the delta smelt, its critical habitat, and the 


[[Page 5978]]

splittail. With respect to each project, we concluded that it was 

likely to jeopardize the continued existence of both species, and to 

cause the destruction or adverse modification of the delta smelt's 

critical habitat. In each of these examples, we expressly found that an 

activity that would destroy or adversely modify critical habitat for 

the delta smelt would also jeopardize its continued existence. In each 

case, the project's primary impacts to the splittail, and the primary 

bases for our conclusion that the splittail would be jeopardized by the 

project, were habitat impacts. Moreover, had critical habitat been 

proposed for the splittail, neither these conferences nor any of the 

others regarding the splittail would have resulted in a finding of 

adverse modification without a complementary finding of jeopardy.

    Apart from section 7, the Act provides no additional protection to 

lands designated as critical habitat. Designating critical habitat does 

not create a management plan for the areas where the species occurs; 

does not establish numerical population goals or prescribe specific 

management actions (inside or outside of critical habitat); and does 

not have a direct effect on areas not designated as critical habitat.

    A designation of critical habitat that includes private lands would 

only affect actions where a Federal nexus is present and would not 

confer any additional benefit beyond that already provided through 

section 7 consultation under the jeopardy standard. Designation of 

critical habitat on private lands could, however, result in a detriment 

to the species. The regulatory effect of critical habitat designation 

is often misunderstood by private landowners, particularly those whose 

property boundaries are included within a general description of 

critical habitat for a species. In the past, landowners have mistakenly 

believed that critical habitat designation will be an obstacle to 

development and impose restrictions on the use of their property. In 

some cases, landowners have believed that critical habitat designation 

is an attempt by the government to confiscate their private property. 

As a result of this misunderstanding, critical habitat designation has 

sometimes reduced private landowner cooperation in efforts to conserve 

species listed in California. Because the splittail is found in some 

rivers and tributaries flowing through private lands, the cooperation 

of private landowners is imperative to conserve the splittail. 

Controversy resulting from critical habitat designation has been known 

to reduce private landowner cooperation in the management of other 

listed species (e.g., the northern spotted owl (Strix occidentalis 

caurina) in Oregon, Washington, and California).

    We are concerned that designating critical habitat increases the 

likelihood of intentional acts of vandalism and habitat destruction due 

to widespread public misunderstanding of critical habitat. Within the 

general area where splittail occur, we have documented a number of 

cases where habitat for listed species was deliberately vandalized or 

destroyed to avoid dealing with endangered species regulatory issues. 

Vernal pools, which provide habitat for several listed and candidate 

species, including the giant garter snake (Thamnophis gigas), have been 

affected negatively by landowners rerouting stream courses in order to 

eliminate potential endangered species regulatory effects (F. Muth, 

Fish and Wildlife Service, pers. comm.). We have documented the 

deliberate destruction of habitat for giant garter snakes (K. Hornaday, 

Fish and Wildlife Service, pers. comm.) and valley elderberry longhorn 

beetles (Desmocerus californicus dimorphus) (B. Cordone, Fish and 

Wildlife Service, pers. comm.; S. Pearson, Fish and Wildlife Service, 

pers. comm.; D. Weinrich, Fish and Wildlife Service, pers. comm.; B. 

Twedt, Fish and Wildlife Service, pers. comm.) along irrigation canals 

within the same general areas where the splittail occurs. We are 

concerned that designation of critical habitat for the splittail may 

precipitate further habitat destruction affecting splittail and the 

other species in these habitats.

    We acknowledge that in some situations critical habitat designation 

may provide some value to the species by notifying the public about 

areas important for the species' conservation and calling attention to 

those areas in special need of protection. However, in the case of the 

splittail, we have already spent enormous effort on public outreach and 

education and believe that critical habitat designation for the 

splittail would not provide any further notification or education 

benefit. Subsequent to the publication of the proposed rule to list the 

splittail, we initiated an extensive public outreach strategy to inform 

and educate the general public and interested parties within the range 

of the species. We sent out press releases to local newspapers, 

contacted elected officials, Federal, State, and county agencies, and 

interested parties, including private landowners. We also provided the 

Recovery Plan for the Sacramento/San Joaquin Delta Native Fishes that 

addresses eight fish species including the splittail to these same 

interested parties. We will continue to inform and educate the public 

and private landowners within the range of the species through the 

dissemination of additional information including copies of the final 

rule, fact sheets, and question and answer sheets explaining relevant 

parts of the Act to the parties listed above.

    In addition, up-to-date information about the splittail and its 

habitat, as well as detailed information about the Bay-Delta ecosystem 

and other areas critical to conserving species that utilize the Bay-

Delta, is already widely disseminated to private landowners and to 

entities or individuals that may propose projects that could affect 

splittail. As discussed above in Factor E in the ``Summary of Factors 

Affecting the Species'' section, the CALFED Program is a cooperative 

effort to develop a long term comprehensive plan to restore ecological 

health and improve water management for all beneficial uses of the Bay-

Delta system. In the process of developing a long term plan, CALFED has 

held numerous public meetings, workshops, and hearings throughout the 

State to receive information from the public, as well as to inform the 

public about the program's goals and ecological needs of the species, 

including splittail. CALFED maintains an extensive mailing list in 

order to keep landowners, local, State, and Federal entities, as well 

as the interested public, apprised of CALFED's actions and the 

ecological needs of the species that utilize the Bay-Delta ecosystem 

and other areas necessary for the conservation of species, including 


    Regarding any potential benefit provided by informing other Federal 

and State agencies about the splittail, the knowledge of the range and 

habitat requirements for this species is well known by Federal 

agencies, as is evidenced by the 284 conference reports we have 

prepared addressing the splittail. The Service's Sacramento Field 

Office stores information about the ranges of listed and other 

sensitive species by USGS 7\1/2\ quad maps in a database. When a 

Federal agency notifies the Service about a potential project they may 

authorize, fund, or carry out, the Service does a database search and 

provides a list of species that may be affected by the proposed action. 

The plants and animals that are included on the species list are those 

that may be affected, either directly or indirectly, by the proposed 

project. Fish and other aquatic species including the splittail appear 

on the species list if they are in the same watershed as the proposed 

action. In other words,

[[Page 5979]]

splittail appear on a species list if the action occurs anywhere in the 

Central Valley of California, including all rivers and the tributaries 

that drain to these rivers. This database is updated if new information 

about a species is made available. Use of this database provides a 

superior means of providing information about a species' location to a 

Federal agency.

    Because of the sensitivity of the water community in California, 

State, Federal, and private water users are also very aware of the 

species range and habitat requirements. This knowledge extends to local 

reclamation boards, county boards of supervisors, individual water 

districts as well as a large number of private individuals. Private 

consultants, who provide the biological expertise for all of the above 

mentioned publics, have developed extensive knowledge of the current 

range, habitat requirements, and potential effects of project proposals 

on the splittail. Designation of critical habitat would not cause us to 

provide different or additional information to these entities for the 

purposes of preserving and/or recovering the species.

    We have evaluated the potential notification and education benefit 

offered by critical habitat designation and find that, for the 

splittail, there would be no additional benefit over the current 

outreach and interagency coordination process currently in place. 

Notification and education can be conducted more effectively by working 

directly with landowners and communities through the recovery 

implementation process and, where a Federal nexus exists, through 

section 7 consultation and coordination. Critical habitat designation 

for the splittail would provide no further notification or education 

benefit. In addition, these existing processes preclude problems and 

potential risks associated with confusion and misunderstanding that may 

accompany a critical habitat designation.

    Critical habitat designation can also aid in the development of a 

species' recovery plan by identifying the areas needing protection or 

requiring special management considerations. However, we have already 

developed the Recovery Plan for the Sacramento/San Joaquin Delta Native 

Fishes that addresses eight fish species, including the Sacramento 

splittail. The Recovery Plan identifies the important habitat areas for 

the splittail.

    In summary, we have determined that the designation of critical 

habitat for the splittail would not be beneficial to the species. For 

the splittail, the section 7 consultation process will produce a 

jeopardy analysis that has results equivalent to a critical habitat 

adverse modification analysis. We already provide private landowners 

and agencies with up-to-date information on important areas for the 

splittail. Federal agencies are already engaged in splittail 

conservation efforts, and we will continue to provide them with up-to-

date information on areas important for splittail conservation. We have 

completed recovery planning for the species, and we will review the 

information in the recovery plan periodically to determine if updates 

and revisions are needed. Finally, even if designation of critical 

habitat for the splittail would provide some small, incremental benefit 

to the species, that benefit is outweighed by the increased risk of (1) 

controversy that would hamper recovery efforts or (2) vandalism. Based 

on this analysis, we conclude that designation of critical habitat for 

the Sacramento splittail is not prudent.

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 

activities. 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 actions be 

carried out for all listed species. We initiate such actions following 

listing. The protection required of Federal agencies and the 

prohibitions against taking and harm 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) of the Act requires Federal agencies to 

confer informally with us 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 

subsequently listed, section 7(a)(2) requires Federal agencies to 

insure 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 action 

may affect a listed species or its critical habitat, the responsible 

Federal agency must enter into consultation with us.

    Federal actions that may affect the splittail include, but may not 

be limited to, those actions authorized, carried out, or funded by the 

Corps, BOR, National Marine Fisheries Service (NMFS), FERC, and USEPA. 

The Corps funds projects and issues permits for water pumping and 

diversion facilities, levee construction or repair, bank protection 

activities, deep-water navigation channel dredging and dredge spoil 

disposal projects, sand and gravel extraction, marina and bridge 

construction, diking of wetlands for conversion to farmland, and tidal 

gate or barrier installation. The BOR and DWR construct, operate, and 

manage water storage and delivery facilities. The FERC licenses and re-

licenses hydroelectric power facilities, that manipulate instream 

flows, in the tributaries to the Sacramento and San Joaquin rivers. The 

USEPA reviews State water quality standards and promulgates replacement 

standards pursuant to the Clean Water Act if State standards are found 

to be inadequate. In 1991, USEPA disapproved portions of the SWRCB's 

WQCP for salinity in the Estuary. Subsequent to that decision, the 

USEPA developed new water quality standards to replace those that were 

disapproved. The USEPA published a proposed rule in December of 1993 

requesting comments. Prior to finalizing the final rule, the State 

developed new water quality standards and proposed a new WQCP, 95-1WR, 

which was implemented, in-part, through Water Rights Order 95-6. The 

USEPA determined that the State's standards provided equivalent or 

better protection and has withdrawn the Federal proposal. The State is 

in the process of developing an implementation plan to fully achieve 

the goals of the WQCP, and is hearing testimony on many issues.

    The Sacramento splittail proposed rule was published January 6, 

1994. During the last 4 years, 284 conference opinions have been 

developed for projects proposed by various Federal agencies. We are 

prepared to adopt all conference opinions as final biological opinions 

for the Sacramento splittail, provided that the respective agencies 

request the adoption in writing and the reinitiation criteria listed 

under 50 CFR 402.16 do not apply. If there have been no significant 

changes in an action as planned or in the information used during the 

conference, we will confirm the conference opinion as the biological 

opinion on the project, and no further section 7 consultation will be 


[[Page 5980]]

    However, reinitiation of formal consultation is required where 

discretionary Federal agency involvement or control over the action has 

been maintained (or is authorized by law) and if--(1) the amount or 

extent of incidental take is exceeded; (2) new information reveals that 

the agency action may affect listed species or critical habitat in a 

manner or to an extent not considered in this opinion; (3) the agency 

action is subsequently modified in a manner that causes an effect to 

the listed species or critical habitat that was not considered in this 

opinion; or (4) a new species is listed or critical habitat designated 

that may be affected by the action. In instances where the amount or 

extent of incidental take is exceeded, any operations causing such take 

must cease pending reinitiation.

    Under section 4 of the Act, listing the splittail provides 

additional impetus for development and implementation of a recovery 

plan to bring together Federal, State, and private efforts to develop 

conservation strategies for this species. We convened the Delta Native 

Fishes Recovery Team to prepare a recovery plan for declining native 

fishes in the Estuary. The draft recovery plan developed a framework 

for agencies to coordinate activities and cooperate with each other in 

conservation efforts. It also set recovery priorities and estimated 

costs of various tasks necessary to accomplish recovery goals. Site-

specific management actions necessary to achieve survival and recovery 

of splittail and other fishes native to the Estuary ecosystem were also 

described in this draft plan. The draft recovery plan was released for 

public review and comment on January 8, 1995 (60 FR 2155). Notice of 

availability of the final plan was published in the Federal Register on 

November 26, 1996 (U.S. Fish and Wildlife Service 1996).

    The Act and implementing regulations set forth a series of general 

prohibitions and exceptions that apply to all threatened wildlife. The 

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 also is illegal to possess, sell, deliver, 

carry, transport, or ship any such wildlife that has been taken 

illegally. Certain exceptions apply to agents of the Service and State 

conservation agencies.

    Our policy, as published in the Federal Register on July 1, 1994 

(59 FR 34272), is 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 if a species is listed. 

Section 9 of the Act prohibits certain activities that directly or 

indirectly affect listed species. The intent of this policy is to 

increase public awareness of the effect of a proposed listing on 

proposed and ongoing activities within a species' range. We believe 

that, based on the best available information, the following actions 

will not result in a violation of section 9, provided these actions are 

carried out in accordance with any existing regulations and permit 


    (1) Routine levee road maintenance;

    (2) Weed and brush control on levees above the mean higher high 

water mark or the ordinary high water mark;

    (3) Aquatic recreational activities;

    (4) Actions that may affect splittail that are authorized, funded 

or carried out by a Federal agency, when the action is conducted in 

accordance with an incidental take statement issued by the Service 

pursuant to section 7 of the Act, and;

    (5) Actions that may affect splittail that are not authorized, 

funded or carried out by a Federal agency, when the action is conducted 

in accordance with an incidental take permit issued by the Service 

pursuant to section 10(a)(1)(B) of the Act.

    Activities that we believe could potentially harm the Sacramento 

splittail and result in ``take'' include, but are not limited to:

    (1) Diversion of water from any river or stream or other water 

course that results in the entrainment, injury or death of splittail, 

including stranding of eggs, larvae, juveniles or adults; or diversions 

that result in the degradation of waters containing splittail;

    (2) Levee slope and bank protection that occurs below the mean 

higher high water mark or the ordinary high water mark of a water body 

that results in the loss of shallow water habitat used by splittail for 

spawning and rearing;

    (3) Dredging in any river or stream or other water body that 

contains Sacramento splittail including dredging in flooded areas where 

splittail may be spawning, or dredging that results in the degradation 

of waters containing splittail;

    (4) Discharge of fill material into a water body supporting 

splittail that results in the destruction or degradation of spawning 

and rearing habitat, substrate composition, water salinity, water 

quality, channel stability, or migratory corridors;

    (5) Discharge or dumping of toxic chemicals, pesticides, organic 

wastes or other pollutants into a water body supporting splittail, or 

discharge or dumping of pollutants that results in the degradation of a 

water body containing splittail; and

    (6) Unauthorized collection of splittail.

    Questions regarding whether specific activities will constitute a 

violation of section 9 should be directed to the Field Supervisor of 

the Service's Sacramento Office (see ADDRESSES section).

    Permits may be issued to carry out otherwise prohibited activities 

involving threatened wildlife species under certain circumstances. 

Regulations governing permits for threatened species are codified at 50 

CFR 17.32. Permits for threatened species 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 are available for zoological exhibition, 

educational purposes, or special functions consistent with the purposes 

of the Act. Requests for copies of the regulations on listed species 

and inquiries regarding permits may be addressed to the U.S. Fish and 

Wildlife Service, Ecological Services, Endangered Species Permits, 911 

NE 11th Avenue, Portland, Oregon 97232-4181 (telephone 503-231-6241; 

facsimilie 503-231-6243).

National Environmental Policy Act

    We have determined that Environmental Assessments and Environmental 

Impact Statements, as defined in 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 


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

[[Page 5981]]

permit and associated requirements for threatened species, see 50 CFR 


References Cited

    A complete list of all references cited in this rule are available 

upon request from the Sacramento Fish and Wildlife Office (see 

ADDRESSES section).


    The primary author of this rule is Michael G. Thabault, U.S. Fish 

and Wildlife Service, Sacramento Office (see ADDRESSES section).

List of Subjects in 50 CFR Part 17

    Endangered and threatened species, Exports, Imports, Reporting and 

recordkeeping requirements, Transportation.

Regulation Promulgation

    Accordingly, part 17, subchapter B of chapter I, title 50 of the 

Code of Federal Regulations, is amended 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. In Sec. 17.11(h) add the following to the List of Endangered and 

Threatened Wildlife in alphabetical order under ``FISHES:'

Sec. 17.11  Endangered and threatened wildlife.

* * * * *

    (h) * * *


                        Species                                                    Vertebrate

--------------------------------------------------------                        population where                                  Critical     Special

                                                            Historic range       endangered or         Status      When listed    habitat       rules

           Common name                Scientific name                              threatened



                *                   *                   *                   *                   *                   *                   *

Splittail, Sacramento............  Pogonichthys          U.S.A. (CA)........  Entire.............  T                       656           NA           NA


                *                   *                   *                   *                   *                   *                   *


    Dated: February 1, 1999.

Jamie Rappaport Clark,

Director, Fish and Wildlife Service.

[FR Doc. 99-2867 Filed 2-5-99; 8:45 am]