Table 7.8. Special-Status Fish Species Potentially Occurring in Napa County
Status
Common and Scientific
Name
Federal/State
California Distribution
Habitats
Occurrence in Napa County
Tidewater goby
Eucyclogobius
newberryi
E/SSC
Restricted to brackish waters of
coastal wetlands. It historically
occurred in at least 87 California
coastal lagoons from San Diego
County to Humboldt County. It
has disappeared from most of
these sites.
Brackish shallow lagoons and lower
stream reaches where the water is fairly
still but not stagnant. Tidewater gobies
have been documented in water with
salinity levels from zero to 10 parts per
thousand (ppt), temperature levels from
35 to 73 degrees Fahrenheit, and water
depths from 5 to 7.5 feet.
Napa estuary within the historic
range, but not collected in any
known surveys of the estuary.
Considered extirpated from the
Napa Estuary.
Delta smelt
Hypomesus
transpacificus
T/T
Found only from the Suisun Bay
upstream through the Delta in
Contra Costa, Sacramento, San
Joaquin, Solano and Yolo
Counties. Their historic range is
thought to have extended from
Suisun Bay upstream to at least
the city of Sacramento on the
Sacramento River and Mossdale
on the San Joaquin River. They
used to be one of the most
common pelagic (living in open
water away from the bottom) fish
in the upper Sacramento-San
Joaquin Estuary.
Tolerant of a wide salinity range. They
have been collected from estuarine
waters up to 14 ppt salinity. For a large
part of their one-year life span, delta
smelt live along the freshwater edge of
the mixing zone (saltwater-freshwater
interface), where the salinity is
approximately 2 ppt.
Captured in the 20-mm seine
surveys of San Pablo Bay
(outside of Napa County)
conducted by DFG from 1995
through 2001, with the exception
of 1997 when delta smelt
apparently were absent.
Table 7.8. Continued
2 of 5
Status
Common and Scientific
Name
Federal/State
California Distribution
Habitats
Occurrence in Napa County
Central California Coast
steelhead trout
Oncorhynchus mykiss
T/--
The Historical distribution
included all coastal river basins
from the Russian River south to
Soquel and Aptos Creek,
California (inclusive), and the
drainages of San Francisco and
San Pablo Bays, including the
Napa River. Current distribution
exists within the same range, but
is limited by habitat availability to
less developed streams and larger
rivers within the range where
cooler temperatures persist.
Habitat requirements change as
steelhead go through different life
phases. Adults require access to natal
streams. The majority of spawning
occurs in the upper reaches of
tributaries. Spawning also requires
gravel in areas free of excessive
sedimentation with adequate flow and
cool, clear water. Escape cover such as
logs, undercut banks, and deep pools for
is also important. Cool (< 70° F), clean
water is essential for survival.
The Napa River watershed
appears to support one of the
larger steelhead runs in the Bay
Area. Anderson (1969)
estimated that the Napa River
watershed at that time might have
supported a run of approximately
500 to 2,000 spawners. Accurate
population estimates for the Napa
River watershed as a whole are
not available (Leidy 1984, Leidy
2001).
Sacramento splittail
Pogonichthys
macrolepidotus
T/SSC
The Sacramento splittail is an
endemic fish of the Sacramento
and San Joaquin River systems
and other drainages of the San
Francisco Bay. Currently, the
distribution is mostly confined to
the delta. Historical distribution
ranged from the delta to the upper
reaches of the Sacramento, San
Joaquin, American, Merced, and
Feather Rivers
Found mainly in fresh water, but can
live in moderate salinity of up to 10-18
ppt. Splittail lay their adhesive eggs on
submerged vegetation in flooded areas
in the lower reaches of rivers and
sloughs. Larvae utilize the shallow,
weedy regions close to spawning sites.
As fish reach adult sizes, they move into
deeper habitat.
Known to occur in the Napa and
Petaluma Rivers and Petaluma
Marsh (U.S. Fish and Wildlife
Service 1993, 1996) near the
Petaluma River and Novato
Creek.
Table 7.8. Continued
3 of 5
Status
Common and Scientific
Name
Federal/State
California Distribution
Habitats
Occurrence in Napa County
Coho salmon
Oncorhynchus kisutch
T/E
Historically known from San
Pablo Bay tributaries; rare in San
Francisco Estuary and tributaries.
Normally spend their first year in fresh
water and their next two years in salt
water prior to returning to spawn in
their natal streams. Some males return
to spawn after only one season in the
ocean. Spawning migrations begin after
heavy, late autumn or winter rains
encourage the returning adult to leave
the ocean and move upstream. In many
of the coastal streams south of San
Francisco Bay, heavy river flows are
needed to breach sand bars that have
formed at the mouths of coastal streams
before fish can migrate up.
Considered extirpated from Napa
County streams, but is included
in NOAA fisheries Critical
Habitat designation (65 FR 7764,
February 16, 2000)
Fall/Late Fall run Chinook
salmon
C/SSC
Winter run Chinook
salmon
Oncorhynchus
tshawytscha
E/E
Current known distribution of the
Fall/late Fall run is limited to
Battle Creek, Cottonwood Creek,
Clear Creek, Mill Creek, Yuba
River and Feather River. The
historic distribution of the late-fall
run is not known, but likely
included the upper Sacramento
River and major tributaries now
blocked by Shasta Dam.
The Winter-run range is
comparable to that of fall/late fall
run chinook, but with a later run
timing (December-March)
Water temperatures and suitable
spawning substrates are the greatest
habitat demands of Chinook salmon.
Coarse gravel must be present in
streambeds for successful spawning,
and stream temperatures below 61°C
are preferred. Chinook commonly
spawn in larger mainstem rivers than
other salmon species.
Both runs have been observed in
the Napa River upstream to the
base of the Kimball Canyon Dam
north of Calistoga (Leidy and
Sisco 1999). These populations
may not be self-sustaining and
may consist of strays from other
basins (NMFS 1999).
Table 7.8. Continued
4 of 5
Status
Common and Scientific
Name
Federal/State
California Distribution
Habitats
Occurrence in Napa County
Green sturgeon
Acipenser medirostris
--/SSC
In California, green sturgeon have
been collected in small numbers in
marine waters from the Mexican
border to the Oregon border. They
have been noted in a number of
rivers, but spawning populations
are known only in the Sacramento
and Klamath Rivers.
In the Sacramento River, adult sturgeon
are in the river, presumably spawning,
when temperatures range between 4558°F. Preferred spawning substrate
likely is large cobble, but can range
from clean sand to bedrock. Eggs are
broadcast-spawned and externally
fertilized in relatively high water
velocities and probably at depths >3 m.
Silt is known to prevent the eggs from
adhering to each other.
A small number of individuals
infrequently collected in DFG
beach seines within San Pablo
Bay near Napa Estuary, but not
in Napa County (CDFG 1999).
Not found within freshwater
reaches of the Napa River
watershed. Individuals may stray
into Napa County.
Longfin smelt
Spirinchus
thaleichthys
--/SSC
Rarely found upstream of Rio
Vista or Medford Island in the
Sacramento-San Joaquin Delta.
Adults occur seasonally as far
downstream as South Bay but they
are concentrated in Suisun, San
Pablo, and North San Francisco
bays. They are rarely collected
outside the estuary.
Occupy mostly the middle or bottom of
the water column in the salt or brackish
water portions of the estuary, although
larval smelt are concentrated in nearsurface brackish waters. Spawning takes
place in fresh water, over sandy-gravel
substrates, rocks, and aquatic plants.
Spawning in the Sacramento-San
Joaquin estuary occurs at water
temperatures of 45-58°F. A strong
positive correlation exists between
winter and spring Delta outflow and
longfin smelt abundance the following
year.
Infrequently collected in DFG
beach seines within San Pablo
Bay near Napa Estuary, but
outside of Napa County (CDFG
1999). Not found within
freshwater reaches of the Napa
River watershed. Individuals
may stray into Napa County.
Table 7.8. Continued
5 of 5
Status
Common and Scientific
Name
River lamprey
Lampetra ayresi
Federal/State
California Distribution
Habitats
Occurrence in Napa County
--/SSC
In California, recorded only from
the lower Sacramento and San
Joaquin rivers and from the
Russian River. A landlocked
population may exist in upper
Sonoma Creek (Sonoma County),
a tributary to San Francisco Bay.
The habitat requirements of spawning
adults and ammocoetes have not been
studied in California. Presumably, the
adults need clean, gravelly riffles in
permanent streams for spawning, while
the ammocoetes require sandy
backwaters or stream edges in which to
bury themselves, where water quality is
continuously high and temperatures do
not exceed 77°F.
Infrequently collected in DFG
beach seines within San Pablo
Bay near the Napa Estuary, but
not in the portion of the estuary
in Napa County (CDFG 1999).
Historically collected within the
Napa River watershed, but not
currently known to occur.
Status explanations:
Federal
E
=
listed as endangered under the federal Endangered Species Act.
T
=
listed as threatened under the federal Endangered Species Act.
C
=
candidate for listing.
-=
no listing.
State
E
=
listed as endangered under the California Endangered Species Act.
T
=
listed as threatened under the California Endangered Species Act.
FP =
fully protected under the California Fish and Game Code.
SSC =
species of special concern in California.
-=
no listing.