Endangered and Threatened Wildlife and Plants; Revised Proposed Critical Habitat Determination for the Delta Smelt

DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AB66

Endangered and Threatened Wildlife and Plants; Revised Proposed

Critical Habitat Determination for the Delta Smelt

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: The Fish and Wildlife Service (Service) revises its proposed

designation of critical habitat for the delta smelt (Hypomesus

transpacificus) originally published on October 3, 1991, concurrently

with the proposal to list the species, pursuant to the Endangered

Species Act of 1973, as amended (Act). The final rule listing the delta

smelt as a threatened species was published on March 5, 1993. In the

final rule, the Service postponed the decision on critical habitat

determination for up to 1 year beyond the date that the final rule was

due (October 3, 1993) in accordance with section 4(b)(6)(C)(ii) of the

Act. The Service has refined the primary constituent elements described

in the original critical habitat proposal. This revised proposed rule

supersedes all aspects of the Service's previous proposal. Critical

habitat designation for the delta smelt would provide additional

protection under section 7 of the Act with regard to activities that

require Federal agency action. As required by section 4 of the Act, the

Service will consider economic and other relevant impacts prior to

making a final decision on the size and configuration of critical

habitat. The Service solicits data and comments from the public on all

aspects of this revised proposal.

DATES: Comments from all interested parties must be received by March

7, 1994. Public hearing requests must be received by February 22, 1994.

ADDRESSES: Comments and materials concerning this proposal should be

sent to the Acting Field Supervisor, Fish and Wildlife Service,

Sacramento Field Office, 2800 Cottage Way, room E-1803, Sacramento,

California 95825-1846. Comments and materials received will be

available for public inspection, by appointment, during normal business

hours at the above address.

FOR FURTHER INFORMATION CONTACT: Dale Pierce, Sacramento Field Office

(see ADDRESSES section) at (916) 978-4866.

SUPPLEMENTARY INFORMATION:

Background

Previous Service Action

In the January 6, 1989 (50 FR 554), Animal Notice of Review, the

Service included the delta smelt as a category 1 candidate species.

Category 1 includes species for which data in the Service's possession

are sufficient to support proposals for listing. On June 29, 1990, the

Service received a petition dated June 26, 1990, from Dr. Don C. Erman,

President-Elect of the California-Nevada Chapter of the American

Fisheries Society, to list the delta smelt as an endangered species

with critical habitat. The Service made a 90-day finding that

substantial information had been presented indicating that the

petitioned action may be warranted and announced this decision in the

Federal Register on December 24, 1990 (55 FR 52852). On October 3, 1991

(56 FR 50075), the Service published a proposal to list the delta smelt

as a threatened species and to designate critical habitat. This

proposed rule constituted the 12-month petition finding in accordance

with section 4(b)(3)(B) of the Act.

Critical habitat was proposed for areas of all water and all

submerged lands below ordinary high water and the entire water column

bounded by and contained within Suisun Bay (including the contiguous

Grizzly and Honker Bays), the length of Montezuma Slough, portions of

the Sacramento River, portions of the Sacramento-San Joaquin Delta,

portions of the San Joaquin River, and the contiguous water bodies in

between (a complex of bays, dead-end sloughs, channels typically less

than four meters deep, marshlands, etc.), California. The public

comment period opened on the date of publication of the proposed rule

(October 3, 1991) and closed on January 31, 1992.

The Service published a notice of public hearing on the proposed

rule on December 19, 1991 (56 FR 65877). Public hearings were conducted

in California on January 9, 1992, in Sacramento; on January 14, 1992,

in Santa Monica; and on January 16, 1992, in Visalia. At each meeting,

testimony was taken from 1 p.m. to 4 p.m. and from 6 p.m. to 9 p.m.

The final rule listing the delta smelt as a threatened species was

published on March 5, 1993 (58 FR 12854). In the final rule, the

Service postponed the decision on critical habitat designation for up

to 1 year beyond the date that the final rule was due (October 3, 1993)

in accordance with section 4(b)(6)(C)(ii) of the Act. The economic

analysis necessary to determine critical habitat was still in progress

at that time. On March 16, 1993 (58 FR 14199), the Service published a

notice that the public comment period on the proposed designation of

critical habitat for the delta smelt was reopened until April 30, 1993,

to allow the Service to consider any information that previously had

not been submitted.

Revisions to the October 3, 1991, Critical Habitat Proposal

The Service is required to base critical habitat designations on

the best scientific and commercial data available (50 CFR 424.12).

Subsequent to publication of the October 3, 1991, proposed rule, the

Service received new information on the current distribution of the

delta smelt, primarily from other State and Federal agencies.

Based primarily on information gathered by the California

Department of Fish and Game (Dale Sweetnam, California Department of

Fish and Game, pers. comm., 1993) and University of California, Davis

(Lesa Meng, University of California, pers. comm., 1993), the Service

proposes to expand the geographic extent of critical habitat to include

additional areas now known to constitute important spawning habitat. In

1993, delta smelt spawned in the Sacramento River, at least as far

upstream as Sacramento and Barker, Lindsey, Cache, Georgiana, Prospect,

Beaver, Hog, and Sycamore Sloughs (Dale Sweetnam, pers. comm., 1993).

In 1991, when delta smelt had all but disappeared from Suisun Marsh,

relatively large numbers of delta smelt were caught in Suisun Slough,

as far upstream as Suisun City (Lesa Meng, pers. comm., 1993). For

these reasons, the proposed critical habitat has been revised to

encompass these upstream habitats. Protection of these upstream

spawning habitats is essential to ensure recovery of the species.

Hence, this rule proposes critical habitat for the following geographic

area: Areas of all water and all submerged lands below ordinary high

water and the entire water column bounded by and contained in Suisun

Bay (including the contiguous Grizzly and Honker Bays); the length of

Goodyear, Suisun, Cutoff, First Mallard (Spring Branch), and Montezuma

Sloughs; and the existing contiguous waters contained within the Delta.

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

contained within the legal definition of the Sacramento-San Joaquin

Delta, as delineated by section 12220 of the State of California's

Water Code of 1969.

In an April 23, 1993, letter, received during the public comment

period, the Environmental Protection Agency (EPA) requested that new

scientific information presented in its draft proposed Bay/Delta water

quality standards be considered in the Service's designation of

critical habitat. The Service has used this information to refine the

primary constituent elements described in the original critical habitat

proposal. (The term ``primary constituent element'' is defined in the

``Primary Constituent Elements'' section of this rule.) The Service's

original proposal listed the following constituent elements: Space for

population growth, cover or shelter, maintenance of appropriate

littoral zone reproduction habitat to sustain embryos and to rear

larvae and juveniles, and 0-2 parts per thousand (ppt) salinities

during the January to June delta smelt reproductive season. As part of

the background for formulation of its proposed water quality standards,

EPA analyzed the number of days that low salinity (2 ppt) water

historically was located at three positions in Suisun Bay. The revised

primary constituent elements incorporate this new information. As

described in the ``Primary Constituent Elements'' section of this rule,

the Service has revised the primary constituent elements to include

those features that provide temporal and spatial variability of low

salinity waters that will deter further invasion of exotic species,

produce high zooplankton densities for food, and simulate natural

processes and historical conditions. The primary constituent elements

also describe in detail the months that each delta smelt life stage

requires protective habitat conditions.

After considering the information presented by EPA, the Service has

determined that, if implemented, EPA's proposed water quality standards

would likely significantly affect critical habitat as proposed in the

October 3, 1991, rule. Consequently, the Service is proposing this

revised rule to reduce the potential for inconsistencies between EPA's

standards and the Service's proposed critical habitat. Resolving the

inconsistencies will afford the smelt the same or better protection as

would have been achieved through the earlier proposal.

Relationship Between Fish and Wildlife Service and EPA Actions

The Clean Water Act and Endangered Species Act as written do not

specify how government actions should be coordinated or agency

conflicts should be resolved. However, because the Service and EPA

recognize that their proposed regulatory actions overlap both

biologically and economically, both agencies are working closely to

provide a comprehensive, ecosystem-based approach to the protection of

the fish and wildlife resources of the San Francisco Bay/Sacramento-San

Joaquin Delta Estuary. This coordination should also provide a set of

regulatory actions that are integrated in both substance and timing.

Section 7 of the Endangered Species Act requires that all Federal

agencies ensure that their actions do not jeopardize the continued

existence of listed species or adversely modify listed species'

critical habitat. EPA's proposed action to designate water quality

standards must comply with the section 7 requirement. EPA has initiated

a formal consultation process under section 7. Additionally, the Clean

Water Act requires protection of the most sensitive use within each

category of designated uses. Protection of endangered and threatened

species is considered a designated use within the meaning of the Clean

Water Act; therefore, a species listing under the Endangered Species

Act provides one method to identify the most sensitive use within the

designated uses of a water body.

Biologically, the proposed critical habitat for the delta smelt and

the salinity criteria that constitute EPA's proposed water quality

standards are directly related. Specifically, the occurrence of

salinities of 2 parts per thousand (ppt) in Suisun Bay was identified

as a critical habitat primary constituent element in the October 3,

1991, critical habitat proposal. Subsequent scientific publications

indicate that salinities associated with the distribution of delta

smelt may provide the best basis for setting standards for many species

that are affected by freshwater discharge from the Bay/Delta Estuary.

Favorable conditions from February through June are extremely important

to the abundance and reproductive success of almost all species that

live in or migrate through the upper Bay/Delta Estuary. EPA's proposed

water quality standards address the location of 2 ppt salinities from

February to June and, therefore, address both critical habitat

requirements for delta smelt and a range of interrelated parameters

that affect other species that rely on estuarine habitat.

Habitat Requirements

Historically, the delta smelt is thought to have occurred from

Suisun Bay upstream to the city of Sacramento on the Sacramento River

and Mossdale on the San Joaquin River (Moyle et al. 1992). Recently,

however, Wang (1991) recorded larval delta smelt from the Sacramento

River as far north as its confluence with the Feather River. The delta

smelt is an euryhaline species (tolerant of a wide salinity range) that

spawns in fresh water and has been collected from estuarine waters up

to 14 grams per liter (ppt) salinity (Moyle et al. 1992). For a large

part of its annual life span, this species is associated with the

freshwater edge of the entrapment zone (mixing zone at the saltwater-

freshwater interface), where the salinity is approximately 2 ppt

(Ganssle 1966, Moyle et al. 1992, Sweetnam and Stevens 1993).

The delta smelt is adapted to living in the highly productive

Sacramento-San Joaquin River Estuary (Estuary) where salinity varies

spatially and temporally according to tidal cycles and the amount of

freshwater inflow. (The term estuary refers to a partially enclosed

water body of variable salinity with freshwater and seawater inflow.)

Despite this tremendously variable environment, the historical Estuary

probably offered relatively constant suitable habitat conditions to

delta smelt, which could move upstream or downstream with the

entrapment zone (Peter Moyle, University of California, pers. comm.,

1993). Since the 1850s, however, the amount and extent of suitable

habitat for the delta smelt has declined dramatically. The advent in

1853 of hydraulic mining in the Sacramento and San Joaquin Rivers led

to increased siltation and alteration of the circulation patterns of

the Estuary (Nichols et al. 1986, Monroe and Kelly 1992). The

reclamation of Merritt Island for agricultural purposes in the same

year marked the beginning of the present-day cumulative loss of 94

percent of the Estuary's tidal marshes (Nichols et al. 1986, Monroe and

Kelly 1992).

In addition to this degradation and loss of estuarine habitat, the

delta smelt has been increasingly subject to entrainment, upstream or

reverse flows of waters in the Delta and San Joaquin River, and

constriction of habitat in the less productive, deep-water river

channels of the Delta (Moyle et al. 1992). These adverse conditions are

primarily a result of the steadily increasing proportion of water

diverted from the Delta by the Federal and State water projects (Monroe

and Kelly 1992). Water delivery through the Federal Central Valley

Project began in water year 1940. The State Water Project began

delivering water in 1968. However, the proportion of fresh water being

diverted has increased since 1983 and has remained at high levels

(Moyle et al. 1992). The high proportion of fresh water exported has

exacerbated the already harsh environmental conditions experienced by

the delta smelt during the recent 6-year drought. The March 5, 1993 (58

FR 12854), final rule listing the delta smelt as a threatened species

describes in detail the factors that have led to this species' decline.

This revised proposed rule to designate critical habitat for the

delta smelt focuses on habitat conditions required during specific life

stages (spawning, larval and juvenile transport, rearing, and adult

migration) of this annual species to ensure its eventual recovery.

Shortly before spawning, adult delta smelt migrate upstream from the

highly productive brackish-water habitat associated with the entrapment

zone to disperse widely into river channels and tidally-influenced

backwater sloughs (Radtke 1966, Moyle 1976, Wang 1991). Migrating

adults with nearly mature eggs have been taken at the Central Valley

Project's Tracy Pumping Plant from late December 1990 to April 1991

(Wang 1991).

Delta smelt spawn in shallow, fresh or slightly brackish water

upstream of the entrapment zone (Wang 1991). Most spawning occurs in

tidally-influenced backwater sloughs and channel edgewaters (Moyle

1976; Wang 1986, 1991; Moyle et al. 1992). Although delta smelt

spawning behavior has not been observed (Moyle et al. 1992), the

adhesive, demersal eggs are thought to attach to substrates such as

cattails and tules, tree roots, and submerged branches (Moyle 1976,

Wang 1991). In the Delta, spawning is known to occur in the Sacramento

River and in Barker, Lindsey, Cache, Georgiana, Prospect, Beaver, Hog,

and Sycamore Sloughs (Wang 1991; Dale Sweetnam, pers. comm., 1993).

Delta smelt also spawn north of Suisun Bay in Montezuma and Suisun

Sloughs and their tributaries (Dale Sweetnam, pers. comm., 1993; Lesa

Meng, pers. comm., 1993).

The spawning season varies from year to year and may occur from

late winter (December) to early summer (July). Moyle (1976) collected

gravid adults from December to April, although ripe delta smelt were

most common in February and March. In 1989 and 1990, Wang (1991)

estimated that spawning had taken place from mid-February to late June

or early July, with the peak spawning period occurring in late April

and early May.

Based on data for a closely related species, delta smelt eggs

probably hatch in 12 to 14 days (Moyle et al. 1992). After hatching,

larvae are transported downstream toward the entrapment zone where they

are retained by the vertical circulation of fresh and salt waters

(Stevens et al. 1990). The pelagic larvae and juveniles feed on

zooplankton. When the entrapment zone is located in a broad geographic

area with extensive shallow-water habitat within the euphotic zone

(depths less than 4 meters), high densities of phytoplankton and

zooplankton are produced (Arthur and Ball 1978, 1979, 1980), and larval

and juvenile fish, including delta smelt, grow rapidly (Moyle et al.

1992, Sweetnam and Stevens 1993). In general, estuaries are among the

most productive ecosystems in the world (Goldman and Horne 1983).

Estuarine environments produce an abundance of fish as a result of

plentiful food and shallow, protective habitat for young.

When the entrapment zone is contained within Suisun Bay, young

delta smelt are dispersed widely throughout a large expanse of shallow-

water and marsh habitat. Dispersion in areas downstream from the State

and Federal water pumps and in-Delta agricultural diversions protects

young smelt from entrainment and distributes them among the extensive,

protective, and highly productive shoal regions of Suisun Bay. In

contrast, when located upstream, the entrapment zone becomes confined

in the deep river channels, which are smaller in total surface area,

contain fewer shoal areas, have swifter, more turbulent water currents,

and lack high zooplankton productivity.

Erkkila et al. (1950) collected young delta smelt near Sherman

Island, at the confluence of the Sacramento and San Joaquin Rivers, in

July and August of 1948. In studies by the California Department of

Fish and Game, California Department of Water Resources, and Bureau of

Reclamation, larval and juvenile delta smelt were collected from Roe

Island in Suisun Bay north to the confluence of the Sacramento and

Feather Rivers and east to Medford Island on the San Joaquin River

(Wang 1991). These studies were conducted during the months of April

through mid-July in 1989 and 1990. Through these distribution surveys,

Wang (1991) was able to document the movement of juvenile delta smelt

from the Delta to Suisun Bay in late June and early July. In 1990,

young delta smelt were taken at the Tracy Pumping Plant at the end of

February (Wang 1991).

Critical Habitat

Critical habitat is defined in section 3(5)(A) of the Act as ``(i)

the specific areas within the geographic area occupied by the species *

* * 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 the species at the time

it is listed * * * upon a determination * * * that such areas are

essential for the conservation of the species.'' The term

``conservation,'' as defined in section 3(3) of the Act, means ``* * *

to use and the use of all methods and procedures which are necessary to

bring an endangered species or threatened species to the point at which

the measures provided pursuant to this Act are no longer necessary.''

Therefore, areas designated as critical habitat must contain those

physical or biological features essential to recover a species to the

point that it no longer requires protection under the Act. Hence,

critical habitat designation affords species additional protection

above and beyond those of listing in that it preserves options for the

species' eventual recovery. Section 3 further states that in most cases

the entire range of a species should not be encompassed within critical

habitat.

Critical habitat designations alert Federal and State agencies,

other organizations, and the public about the importance of an area in

the conservation of a listed species. Critical habitat also identifies

areas that may require special management or protection. Critical

habitat receives protection under section 7 of the Act with regard to

actions carried out, funded, or authorized by Federal agencies. Section

7 requires that Federal agencies consult on actions that may affect

critical habitat to ensure that their actions are not likely to destroy

or adversely modify critical habitat. Section 7 also requires Federal

agencies to confer on Federal actions that are likely to result in

adverse modification or destruction of proposed critical habitat. Aside

from the added protection provided under section 7, the Act does not

provide other direct forms of protection to lands designated as

critical habitat.

In addition to considering biological information in designating

critical habitat, the Service also considers economic and other

relevant impacts of designating critical habitat. The Secretary may

exclude areas from critical habitat when the benefits of such exclusion

outweigh the benefits of including the areas within critical habitat,

provided that the exclusion will not result in the extinction of a

species.

Primary Constituent Elements

In determining which areas to designate as critical habitat, the

Service considers those physical and biological features that are

essential to a species' conservation (50 CFR 424.12). The Service is

required to list the known primary constituent elements together with a

description of any critical habitat that is proposed. Such physical and

biological features (i.e., primary constituent elements) include, but

are not limited to, the following:

(1) Space for individual and population growth, and for normal

behavior;

(2) Food, water, air, light, minerals, or other nutritional or

physiological requirements;

(3) Cover or shelter;

(4) Sites for breeding, reproduction, rearing of offspring,

germination, or seed dispersal; and

(5) Generally, habitats that are protected from disturbance or are

representative of the historic geographical and ecological

distributions of a species.

Following are the primary constituent elements necessary to

conserve the delta smelt. These elements were determined in

coordination with EPA in preparation of its proposed water quality

standards. EPA's proposed rule to promulgate Water Quality Standards

for Surface Waters of the Sacramento River, San Joaquin River, and San

Francisco Bay and Delta of the State of California is published in this

same Federal Register separate part. In its proposed rule, EPA has

requested specific comments on several issues, including the

possibility of modifying the Sacramento River Index for the purposes of

developing the salinity criteria, alternative approaches to the

averaging period used in its proposed salinity criteria, and evaluation

of the merits of the use of difference forms of confidence intervals

with the proposed criteria. The Fish and Wildlife Service will consider

these comments also in developing its final rule.

The primary constituent elements are organized by habitat

conditions required for each life stage. The specific geographic areas

and seasons identified for each habitat condition specified below

represent the maximum possible range of each of these variables.

Each of the habitat conditions specified below requires as its

basis placement of the 2 ppt isohaline at or downstream of the

Sacramento-San Joaquin River confluence from February through June. (An

isohaline is a line that can be drawn to connect all points of equal

salinity.) Furthermore, the location of the 2 ppt isohaline must vary

according to water years because:

(1) Temporal and spatial variability of the 2 ppt isohaline will be

the most effective deterrent to further invasion of new introduced

species and continued competition by those that are already

established,

(2) Placement of the 2 ppt isohaline in an area will also produce

the high phytoplankton and zooplankton densities that characterize most

healthy estuarine ecosystems, and

(3) Variability is needed to simulate natural processes and

historical conditions.

Table 1 lists the number of days (based on a 14-day running

average) that the 2 ppt isohaline must be located at Roe Island, Chipps

Island, or the Sacramento-San Joaquin River confluence during wet,

above normal, below normal, dry, and critically dry years to achieve

the life-stage habitat conditions described below. These required

salinity criteria are based on historical records of the water years

between October 1939 (subsequent to the operation of the Federal and

State water projects) and September 1975 (prior to the decline of the

delta smelt) (Harry Seraydarian, EPA, in litt., 1993; Bruce Herbold,

EPA, pers. comm., 1993). However, because no critically dry years

occurred during this period, the salinity criteria (required number of

days) for these years are based on an extrapolation of the data.

Table 1.--Required Salinity Criteria for Suisun Bay to Reflect

Historical Habitat Conditions

[Values represent the number of days that the 2 ppt isohaline must be

placed at three locations within the Sacramento-San Joaquin River

Estuary]

------------------------------------------------------------------------

Roe Island [km Chipps Island Confluence [km

Year type 64] [km 74] 81]

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Wet..................... 133 148 150

Above normal............ 105 144 150

Below normal............ 78 119 150

Dry..................... 33 116 150

Critically dry.......... 0 90 150

------------------------------------------------------------------------

The Roe Island salinity criteria are meant to replicate natural

spring storm cycles and are invoked only after uncontrolled runoff has

placed the 2 ppt isohaline seaward of Roe Island. Therefore, the

criteria for Roe Island represent the maximum number of days that the 2

ppt isohaline must be located there.

Spawning Habitat--Delta smelt adults seek shallow, tidally-

influenced, freshwater (i.e., less than 2 ppt salinity) backwater

sloughs and edgewaters for spawning. To ensure egg hatching and larval

viability, spawning areas also must provide suitable water quality

(i.e., low concentrations of pollutants) and substrates for egg

attachment (e.g., submerged tree roots and branches and emergent

vegetation). Specific areas that have been identified as important

delta smelt spawning habitat include Barker, Lindsey, Cache, Prospect,

Georgiana, Beaver, Hog, and Sycamore Sloughs and the Sacramento River

in the Delta, and tributaries of northern Suisun Bay. The spawning

season varies from year to year and may start as early as December and

extend until July.

Larval and Juvenile Transport--To ensure that delta smelt larvae

are transported from the area where they are hatched to shallow,

productive rearing or nursery habitat, the Sacramento and San Joaquin

Rivers and their tributary channels must be protected from physical

disturbance (e.g., sand and gravel mining, diking, dredging, and levee

or bank protection and maintenance) and flow disruption (e.g., water

diversions that result in entrainment and in-channel barriers or tidal

gates). Adequate river flow is necessary to transport larvae to rearing

habitat in Suisun Bay. To ensure that suitable rearing habitat is

available in Suisun Bay, the salinity criteria described above in Table

1 are required. Reverse flows that maintain larvae upstream in deep-

channel regions of low productivity and expose them to entrainment

interfere with these transport requirements. Suitable water quality

must be provided so that maturation is not impaired by pollutant

concentrations. The specific geographic area important for larval

transport is confined to waters contained within the legal boundary of

the Delta, Suisun Bay, and Montezuma Slough and its tributaries. The

specific season when habitat conditions identified above are important

for successful larval transport varies from year to year depending on

when peak spawning occurs. Therefore, habitat conditions suitable for

transport of larvae and juveniles may be required as early as February

1 and as late as August 31.

Rearing Habitat--Maintenance of the 2 ppt isohaline (according to

the salinity criteria described in Table 1) and suitable water quality

(low concentrations of pollutants) within the Estuary is necessary to

provide delta smelt larvae and juveniles a shallow, protective, food-

rich environment in which to mature to adulthood. This placement of the

2 ppt isohaline also serves to protect larval, juvenile, and adult

delta smelt from entrainment in the State and Federal water projects.

However, additional flows above those required to implement the

February through June salinity criteria listed in Table 1 may be

required occasionally to protect larval and juvenile delta smelt from

being entrained in the State and Federal water projects during the

months of July and August. These additional flows will be required when

the previous year's abundance indices show that the adult population

already is at low levels and late spawning conditions have led to

distribution of larval and juvenile delta smelt upstream of the

confluence of the Sacramento and San Joaquin Rivers in July and August.

An area extending eastward from Carquinez Straits, including Suisun

Bay, Grizzly Bay, Honker Bay, Montezuma Slough and its tributary

sloughs, up the Sacramento River to its confluence with Three Mile

Slough, and south along the San Joaquin River including Big Break,

defines the specific geographic area critical to the maintenance of

suitable rearing habitat. Three Mile Slough represents the approximate

location of the most upstream extent of tidal excursion when the

salinity criteria described in Table 1 are implemented. Protection of

rearing habitat conditions may be required from the beginning of

February to the end of August.

Adult Migration--Adult delta smelt must be provided unrestrained

access to suitable spawning habitat in a period that may extend from

December to July. Therefore, adequate flow and suitable water quality

must be maintained to attract migrating adults in the Sacramento and

San Joaquin River channels and their associated tributaries, including

Cache and Montezuma Sloughs and their tributaries. These areas also

must be protected from physical disturbance and flow disruption during

migratory periods.

To conserve the delta smelt, critical habitat is proposed for an

area encompassing the specific habitat conditions required by each life

stage identified above. Accordingly, critical habitat is proposed for

the following geographic area: Areas of all water and all submerged

lands below ordinary high water and the entire water column bounded by

and contained in Suisun Bay (including the contiguous Grizzly and

Honker Bays); the length of Goodyear, Suisun, Cutoff, First Mallard

(Spring Branch), and Montezuma Sloughs; and the existing contiguous

waters contained within the Delta. The proposed critical habitat is

contained within Contra Costa, Sacramento, San Joaquin, Solano, and

Yolo Counties, California. The ``Proposed Regulations Promulgation''

section provides a precise metes and bounds description of the revised

proposed critical habitat.

Effects of Critical Habitat Designation

Section 7(a)(2) of the Act requires Federal agencies to ensure that

the activities they authorize, fund, or carry out are not likely to

destroy or adversely modify critical habitat. This Federal

responsibility is in addition to the requirement in the same section of

the Act that Federal agencies ensure their actions do not jeopardize

the continued existence of any listed species.

Jeopardy is defined at 50 CFR 402.02 as any action that would be

expected to reduce appreciably the likelihood of both the survival and

recovery of a listed species. Destruction or adverse modification of

critical habitat is defined at 50 CFR 404.02 as a direct or indirect

alteration that appreciably diminishes the value of critical habitat

for both the survival and recovery of a listed species. The regulations

also clearly state that such alterations include, but are not limited

to, alterations adversely modifying any of those physical or biological

features that were the basis for determining the habitat to be

critical. The requirement to consider potential adverse modification of

critical habitat is an incremental consideration above and beyond the

review necessary to evaluate the likelihood of jeopardy and incidental

take in section 7 consultations. In section 7 consultations, the

Service considers the potential for adverse modification of the primary

constituent elements identified in the critical habitat designation.

Section 4(b)(8) of the Act requires for any proposed or final

regulation that designates critical habitat a brief description and

evaluation of those activities (public or private) that may adversely

modify such habitat or may be affected by such designation. The Service

has identified the following list of activities that, depending on the

season of construction and scale of the project, may result in the

destruction or adverse modification of critical habitat without

necessarily jeopardizing the continued existence of the delta smelt:

(1) Sand and gravel extraction in river channels or marshes;

(2) Diking wetlands for conversion to farmland and dredging to

maintain these dikes;

(3) Levee maintenance and bank-protection activities, such as

riprapping, removal of vegetation, and placement of dredged materials

on levees of banks;

(4) Operation of the Montezuma Slough Control Structure; and

(5) Bridge and marina construction.

Construction and implementation of each of these actions requires

authorization by the Army Corps of Engineers pursuant to section 10 of

the Rivers and Harbors Act of 1899 and section 404 of the Clean Water

Act. Based on the Service's review of all existing or proposed projects

that may affect the delta smelt, the great majority that would likely

result in destruction or adverse modification of critical habitat also

would be likely to jeopardize the continued existence of the species.

The Service has not identified any proposed actions that might

jeopardize the delta smelt without adversely affecting its critical

habitat.

Considerations of Economic and Other Factors

Section 4(b)(2) of the Act requires the Service to consider

economic and other relevant impacts of specifying any particular area

to be included within the critical habitat boundary. The Secretary may

exclude any area from critical habitat should it be determined that the

benefits of such exclusion outweigh the benefits of specifying such an

area as part of the critical habitat unless it is determined, based on

the best scientific and commercial data available, that the failure to

designate such an area as critical habitat will result in the

extinction of the species concerned.

The impacts of designating critical habitat are in addition to the

economic and other impacts attributable to listing of the species.

Impacts attributable to listing include those resulting from the taking

prohibitions under section 9 of the Act and associated regulations.

``Take,'' as defined in section 3(18) of the Act, includes harm to a

listed species. ``Harm'' means an act that actually kills or injures

wildlife. Such an act may include significant habitat modification or

degradation where it actually kills or injures wildlife by

significantly impairing essential behavioral patterns, including

feeding, breeding, or sheltering (50 CFR 17.3).

Impacts attributable to listing also include those resulting from

the responsibility of Federal agencies under section 7 to ensure that

their actions are not likely to jeopardize the continued existence of

endangered or threatened species. An action could be likely to

jeopardize the continued existence of a listed species through the

destruction or modification of its habitat regardless of whether that

habitat has been formally designated as critical. The Act provides

significant protection to species, including protection to their

habitats, as a result of listing. Therefore, the direct economic and

other impacts resulting from additional habitat protection through

critical habitat designation may be incrementally small. In general,

the designation of critical habitat supplements the substantive

protection resulting from listing.

EPA has prepared a draft Regulatory Impact Analysis on its proposed

water quality standards. EPA's draft Regulatory Impact Analysis

includes an economic analysis of the effects of the designation of

critical habitat for the delta smelt. This economic analysis concludes

that economic costs attributable to the designation of critical habitat

for the delta smelt are relatively small and due primarily to the

effects designation of critical habitat would have upon the five types

of actions listed above under the section entitled ``Effects of

Critical Habitat Designation.'' An underlying assumption of the draft

economic analysis is that the costs associated with implementing EPA's

proposed water quality standards for the Bay/Delta are due primarily to

listing the delta smelt as threatened. As the Service refines its

economic analysis, it may determine that this assumption is to some

degree inappropriate and that some of the costs associated with

implementing the water quality standards may be attributable to the

designation of critical habitat.

The costs associated with sand and gravel operations (approximately

two aggregate operators are located in the Delta), diking or dredging

for agricultural activities, and marina or bridge construction are

expected to be similar. Project proponents or operators would incur

costs associated with wetlands restoration, using a replacement ratio

of 3 acres restored for 1 acre destroyed. The cost to restore 1 acre of

wetlands ranges between $10,000 and $50,000. However, for some tracts

of land, the costs associated with restoring wetlands may exceed the

value derived from the agricultural activity, in which case the cost

attributable to critical habitat would be the loss in agricultural

income. The costs attributable to a designation of critical habitat are

not expected to substantially affect levee maintenance operations

because Federal regulatory agencies currently have restrictions that

generally avoid adverse effects to the delta smelt. However, the

designation of critical habitat may result in leaving the Montezuma

Slough Control Structure's gates open from December to August rather

than November to March.

The Service will prepare a final economic analysis prior to making

its final determination on critical habitat. If that analysis

substantially differs from the draft summarized here, the Service will

make a revised economic analysis available to the public for comment

prior to a final determination on critical habitat.

Available Conservation Measures

Conservation measures provided to species listed as endangered or

threatened under the Endangered Species Act include recognition,

recovery actions, requirements for Federal protection, and prohibitions

against certain activities. Recognition through listing encourages and

results in conservation actions by Federal, State, and private

agencies, groups, and individuals. The Endangered Species Act provides

for possible land acquisition and cooperation with the States and

requires that recovery actions be carried out for all listed species.

Such actions are initiated by the Service 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 the Service 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 and its critical habitat is designated,

section 7(a)(2) requires Federal agencies to ensure that activities

they authorize, fund, or carry out are not likely to jeopardize the

continued existence of such a species or to destroy or adversely modify

its critical habitat. If a Federal action may affect a listed species

or its critical habitat, the responsible Federal agency must enter into

consultation with the Service.

Survival and recovery, mentioned in both the definition of adverse

modification and jeopardy (see ``Effects of Critical Habitat

Designation'' section), are directly related. Survival may be viewed as

a linear continuum between recovery and extinction of the species. The

closer a species is to recovery, the greater the certainty of the

species' continued survival. Thus, the terms survival and recovery are

related by the degree of certainty that the species will persist over a

given period of time. Survival relates to viability. Factors that

influence a species' viability include population numbers, distribution

throughout the range, stochasticity, expected duration, and

reproductive success. A species may be considered recovered when there

is a high degree of certainty for the species' continued viability.

The Act's definition of critical habitat indicates that the purpose

of critical habitat is to contribute to a species' conservation, which,

by definition, means recovery. Section 7 prohibitions against the

destruction or adverse modification of critical habitat apply to

actions that would impair survival and recovery of the listed species,

thus providing a regulatory means of ensuring that Federal actions

within critical habitat are considered in relation to the goals and

recommendations of a recovery plan. As a result of the link between

critical habitat and recovery, the prohibition against destruction or

adverse modification of critical habitat should protect the critical

habitat's ability to contribute fully to a species' recovery. Thus, the

adverse modification standard may be reached closer to the recovery end

of the survival continuum, whereas the jeopardy standard traditionally

has been applied nearer to the extinction end of the continuum.

Federal actions that may affect the delta smelt or its critical

habitat, should any be designated, include those authorized, carried

out, or funded by the Army Corps of Engineers, Bureau of Reclamation,

National Marine Fisheries Service, and EPA. The Army Corps of Engineers

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 Bureau of Reclamation and California

Department of Water Resources construct, operate, and/or manage water

export facilities. EPA reviews State water quality standards and

promulgates replacement standards, pursuant to the Clean Water Act, if

the State standards are found to be inadequate. In 1991, EPA

disapproved portions of the California State Water Resources Control

Board's Water Quality Control Plan for Salinity for the San Francisco

Bay/Sacramento-San Joaquin Delta Estuary. Accordingly, EPA has prepared

proposed replacement standards for those portions of the State's

salinity standards that were disapproved. Measures to protect the

federally listed winter-run chinook salmon, for which the National

Marine Fisheries Service has jurisdiction under the Act, also may

affect the delta smelt and may require consultation with the Service.

Under section 4 of the Act, listing of the delta smelt provided a

requirement for the development of a recovery plan. The Service

convened the Delta Native Fishes Recovery Team to prepare a recovery

plan for declining native fishes in the Sacramento-San Joaquin Estuary.

The recovery plan will develop a framework for Federal, State, and

private entities to coordinate activities and cooperate with each other

in conservation efforts. The plan will set recovery priorities and

estimate the costs of various tasks necessary to accomplish recovery

goals. Site-specific management actions necessary to achieve survival

and recovery of the delta smelt and other fishes native to the Estuary

ecosystem also will be described in this plan.

Summary of Comments and Recommendations

During the 4-month comment period following publication of the

October 3, 1991 (56 FR 50075), proposed rule to list the delta smelt as

threatened and designate its critical habitat, the Service received 360

comments (i.e., letters and oral testimony) from 348 individuals. The

Service received several letters supporting designation of delta smelt

critical habitat as proposed. Many local government agencies, water

districts, business and trade associations, and other private interests

submitted comments regarding the presumed economic effects of the

proposed critical habitat designation on industries, planned

activities, and development in specific municipalities or geographic

regions of California.

On March 16, 1993 (58 FR 14199), the Service published a notice

that the public comment period on the proposed designation of critical

habitat for the delta smelt was reopened until April 30, 1993, to allow

the Service to consider any information that previously had not been

submitted. In response, the Service received seven letters: two in

support of critical habitat designation as proposed, four in

opposition, and a letter from EPA requesting that the Service consider

the biological and hydrological information described in EPA's draft

proposed rule to promulgate Bay/Delta water quality standards.

The proposed rule to designate critical habitat for the delta smelt

has been revised to reflect the best scientific information currently

available and to ensure that the Service coordinates its final actions

with other interested Federal agencies. For this reason, the Service

will address all comments previously received on the economic impacts,

legal requirements, and interpretation of various provisions of the Act

during preparation of a final rule. Additionally, comments received

during the 60-day comment period following publication of this revised

proposed rule will be used in preparing a final rule. Only comments

addressing the issue of available scientific information used to revise

this proposed rule are responded to in this document. In its final

determination on the designation of critical habitat, the Service will

provide a thorough discussion of all comments received in response to

the original proposed rule and to this revised proposed rule.

Comment: EPA requested that in its designation of critical habitat

the Service consider the scientific information described in EPA's

draft proposed rule to promulgate water quality standards for the Bay/

Delta.

Service Response: The Service has substantially revised the primary

constituent elements in this proposed rule to reflect more closely the

historical placement of low salinity estuarine habitat in Suisun Bay.

As part of the background for formulation of its proposed water quality

standards, EPA analyzed the number of days that low salinity (2 ppt)

water historically was located at the confluence of the Sacramento and

San Joaquin Rivers, Chipps Island, and Roe Island in Suisun Bay. The

Service has revised the primary constituent elements to include those

features that provide temporal and spatial variability of low salinity

waters that will deter further invasion of exotic species, produce high

zooplankton densities for food, and simulate natural processes and

historical conditions. The ``Primary Constituent Elements'' section of

this revised proposed rule describes in detail the months that each

delta smelt life stage requires protective habitat conditions. This

revised proposal refines the primary constituent elements to more

accurately replicate historical conditions that are needed to recover

the delta smelt.

Comment: One commenter stated that the Service does not have enough

scientific data to substantiate the conclusions that the location of

low salinity habitat in Suisun Bay is important to the recovery of the

delta smelt, that delta smelt are associated with the saltwater-

freshwater mixing zone, or that water exports could adversely affect

delta smelt critical habitat as currently proposed.

Service Response: Section 4(b)(B)(2) of the Act requires that

critical habitat designations be based on the best scientific data

available. As discussed in the ``Habitat Requirements'' and ``Primary

Constituent Elements'' sections of this rule, the best available

scientific evidence shows that when the entrapment zone is located in a

broad geographic area with extensive shallow-water habitat within the

euphotic zone, high densities of phytoplankton and zooplankton are

produced (Arthur and Ball 1978, 1979, 1980) and larval and juvenile

fish, including delta smelt, grow rapidly (Moyle et al. 1992, Sweetnam

and Stevens 1993). When the entrapment zone is contained within Suisun

Bay, young delta smelt are dispersed widely throughout a large expanse

of shallow-water and marsh habitat (Harry Seraydarian, EPA, in litt.,

1993). Dispersion in areas downstream from the State and Federal water

pumps and in-Delta agricultural diversions protects young smelt from

entrainment (diverted into man-made structures or impinged on screens)

and distributes them among the extensive, protective, and highly

productive shoal regions of Suisun Bay. In contrast, high exports cause

the entrapment zone to be pulled upstream into the deep river channels

(Moyle et al. 1992). The large river channels are smaller in total

surface area, contain fewer shoal areas, have swifter, more turbulent

water currents, and lack high zooplankton densities.

Because the Service seeks to coordinate its final actions with

other interested Federal agencies and because the Service also has

received new distributional information since the October 3, 1991,

proposal to designate critical habitat for the delta smelt, the Service

hereby revises the proposal to designate critical habitat. This

proposed rule revision is based on materials received during the public

comment period and information received during numerous meetings and

discussions with State and Federal agency biologists, ichthyologists,

engineers, and hydrologists. This new proposal supersedes the October

3, 1991, proposal.

Public Comments Solicited

The Service intends that any final action resulting from this

proposal will be as accurate and as effective as possible. Therefore,

comments or suggestions from the public, other concerned governmental

agencies, the scientific community, industry, or any other interested

party concerning this proposed rule are hereby solicited. Comments are

particularly sought concerning:

(1) The reasons why any habitat (either existing or additional

areas) should or should not be determined to be critical habitat as

provided by section 4 of the Act;

(2) Current or planned activities and their possible impacts on

proposed critical habitat areas;

(3) Any foreseeable economic or other impacts resulting from the

proposed designation of critical habitat;

(4) Economic values associated with benefits of designating

critical habitat for the delta smelt; and

(5) The methodology the Service might use, under section 4(b)(2) of

the Act, in determining whether the benefits of excluding an area from

critical habitat outweigh the benefits of specifying the area as

critical habitat. Because the primary constituent elements used in

determining which areas to propose as critical habitat for the delta

smelt were determined in coordination with EPA in preparation of its

proposed water quality standards, the Service also encourages the

public, other concerned governmental agencies, the scientific

community, industry, or any other interested party to provide comments

or suggestions to EPA on its proposed rule to promulgate Water Quality

Standards for Surface Waters of the Sacramento River, San Joaquin

River, and San Francisco Bay and Delta of the State of California. The

Fish and Wildlife Service will consider these comments also in

developing its final rule. EPA's proposed rule is published in this

same Federal Register separate part.

The Endangered Species Act provides for a public hearing on this

proposal, if requested. Requests must be received within 45 days of the

date of publication of this revised proposal in the Federal Register.

Such requests must be made in writing and should be sent to the Acting

Field Supervisor, Sacramento Field Office (see ADDRESSES section).

As stated previously, all comments that have been received during

the preceding public comment periods on the economic impacts, legal

requirements, and biological or ecological requirements or effects of

critical habitat designation will be considered during preparation of a

final rule. Additionally, comments received during the 60-day comment

period following publication of this revised proposed rule will be used

in preparing a final rule. The final decision on the designation of

critical habitat will take into consideration the comments and any

additional information received by the Service and will include any

exclusion determinations.

National Environmental Policy Act

The Service has determined that an Environmental Assessment and/or

an Environmental Impact Statement, as defined under the authority of

the National Environmental Policy Act of 1969, need not be prepared in

connection with regulations adopted pursuant to section 4(a) of the

Act. A notice outlining the Service's reasons for this determination

was published in the Federal Register on October 25, 1983 (48 FR

49244).

Regulatory Flexibility Act and Executive Order 12866

This proposed rule has been reviewed under Executive Order 12866.

The Department of the Interior has determined that the proposed rule

will not have a significant economic effect on a substantial number of

small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et

seq.). Based on the information discussed in this rule concerning

public projects and private activities within critical habitat areas,

significant economic impacts will not result from the critical habitat

designation. Also, no direct costs, enforcement costs, information

collection, or recordkeeping requirements are imposed on small entities

by this designation. Further, the rule contains no recordkeeping

requirements as defined by the Paperwork Reduction Act of 1980.

Takings Implications Assessment

The Service has analyzed the potential takings implications of

designating critical habitat for the delta smelt in a Takings

Implications Assessment prepared pursuant to requirements of Executive

Order 12630, ``Governmental Actions and Interference with

Constitutionally Protected Property Rights.'' The Takings Implications

Assessment concludes that the designation does not pose significant

takings implications.

References Cited

Arthur, J.F., and M.D. Ball. 1978. Entrapment of suspended materials

in the San Francisco Bay-Delta Estuary. U.S. Dept. Interior, Bureau

of Reclamation, Sacramento, California.

Arthur, J.F., and M.D. Ball. 1979. Factors influencing the

entrapment of suspended material in the San Francisco Bay-Delta

Estuary. Pages 143-174 in T.J. Conomos, editor. Pacific Division,

Amer. Assoc. Advance. Sci., San Francisco, California.

Arthur, J.F., and M.D. Ball. 1980. The significance of the

entrapment zone location to the phytoplankton standing crop in the

San Francisco Bay-Delta Estuary. U.S. Dept. Interior, Water and

Power Resources Service.

Erkkila, L.F., J.W. Moffet, O.B. Cope, B.R. Smith, and R.S. Smith.

1950. Sacramento-San Joaquin Delta fishery resources: Effects of

Tracy Pumping Plant and the Delta Cross Channel. U.S. Fish and

Wildlife Service Special Scientific Rept. 56:1-109.

Ganssle, D. 1966. Fishes and decapods of San Pablo and Suisun Bays.

Pages 64-94 in D.W. Kelley, editor. Ecological studies of the

Sacramento-San Joaquin estuary, Part 1. Calif. Dept. Fish and Game,

Fish Bulletin 133.

Goldman, C.R., and A.J. Horne. 1983. Limnology. McGraw-Hill Book

Company, New York, New York.

Monroe, M.W., and J. Kelly. 1992. State of the estuary: A report on

conditions and problems in the San Francisco Bay/Sacramento-San

Joaquin Delta Estuary. San Francisco Estuary Project, Oakland,

California.

Moyle, P.B. 1976. Inland Fishes of California. University of

California Press, Berkeley, California.

Moyle, P.B., B. Herbold, D.E. Stevens, and L.W. Miller. 1992. Life

history and status of delta smelt in the Sacramento-San Joaquin

Estuary, California. Trans. Amer. Fish. Soc. 121:67-77.

Nichols, F.H., J.E. Cloern, S.N. Luoma, and D.H. Peterson. 1986. The

modification of an estuary. Science 231:567-573.

Radtke, L.D. 1966. Distribution of smelt, juvenile sturgeon, and

starry flounder in the Sacramento-San Joaquin Delta with

observations on food of sturgeon. Pages 115-129 in J.L. Turner and

D.W. Kelley, editors. Ecological studies of the Sacramento-San

Joaquin Delta, Part 2. Calif. Dept. Fish and Game, Fish Bulletin

136.

Stevens, D.E., L.W. Miller, and B.C. Bolster. 1990. Report to the

Fish and Game Commission: A status review of the delta smelt

(Hypomesus transpacificus) in California. Calif. Dept. Fish and Game

Candidate Species Status Report 90-2.

Sweetnam, D.A., and D.E. Stevens. 1993. Report to the Fish and Game

Commission: A status review of the delta smelt (Hypomesus

transpacificus) in California. Calif. Dept. Fish and Game Candidate

Species Status Report 93-DS.

Wang, J.C.S. 1986. Fishes of the Sacramento-San Joaquin estuary and

adjacent waters, California: A guide to the early life histories.

Interagency Ecological Study Program for the Sacramento-San Joaquin

Estuary. Tech. Rept. 9.

Wang, J.C.S. 1991. Early life stages and early life history of the

delta smelt, Hypomesus transpacificus, in the Sacramento-San Joaquin

estuary, with comparison of early life stages of the longfin smelt,

Spirinchus thaleichthys. Interagency Ecological Studies Program for

the Sacramento-San Joaquin Estuary. Tech. Rept. 28.

Author

The primary author of this proposed rule is Nadine R. Kanim,

Sacramento Field Office (see ADDRESSES section).

List of Subjects in 50 CFR Part 17

Endangered and threatened species, Exports, Imports, Reporting and

recordkeeping requirements, Transportation.

Proposed Regulations Promulgation

Accordingly, the Service hereby proposes to amend part 17,

subchapter B of chapter I, title 50 of the Code of Federal Regulations,

as set forth below:

PART 17--[AMENDED]

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.

Sec. 17.11 [Amended]

2. Amend Sec. 17.11(h), in the entry in the table under FISHES for

``Smelt, delta,'' in the column under ``Critical habitat'' by revising

``NA'' to read ``17.95(e).''

3. Amend Sec. 17.95(e) by adding critical habitat of the delta

smelt in the same alphabetical order as the species occurs in

Sec. 17.11(h).

Sec. 17.95 Critical habitat--fish and wildlife.

(e) * * *

* * * * *

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Delta Smelt (Hypomesus transpacificus)

California: Areas of all water and all submerged lands below

ordinary high water and the entire water column bounded by and

contained in Suisun Bay (including the contiguous Grizzly and Honker

Bays); the length of Montezuma Slough; and the existing contiguous

waters contained within the Delta, as defined by section 12220, of

the State of California's Water Code of 1969 (a complex of bays,

dead-end sloughs, channels typically less than 4 meters deep,

marshlands, etc.) as follows:

Bounded by a line beginning at the Carquinez Bridge which

crosses the Carquinez Strait, thence northeasterly along the western

and northern shoreline of Suisun Bay, including Goodyear, Suisun,

Cutoff, First Mallard (Spring Branch), and Montezuma Sloughs; thence

upstream to the intersection of Montezuma Slough with the western

boundary of the Delta as delineated in section 12220 of the State of

California's Water Code of 1969; thence following the boundary and

including all contiguous water bodies contained within the statutory

definition of the Delta, to its intersection with the San Joaquin

River at its confluence with Suisun Bay; thence westerly along the

south shore of Suisun Bay to the Carquinez Bridge.

BILLING CODE 4310-55-P

TP06JA94.010

BILLING CODE 4310-55-C

Primary Constituent Elements: Physical habitat, water, river

flow, and salinity concentrations required to maintain delta smelt

habitat for spawning, larval and juvenile transport, rearing, and

adult migration.

Dated: December 10, 1993.

Richard N. Smith,

Acting Director, Fish and Wildlife Service.

[FR Doc. 94-90 Filed 1-5-94; 8:45 am]

BILLING CODE 4310-55-P