(DRAFT) - Taxonomy
Species Bay shrimp
Species Id M070016
Date 26 AUG 96
TAXONOMY
NAME - Bay shrimp
OTHER COMMON NAMES - Franciscan bay shrimp, California shrimp and grass shrimp
ELEMENT CODE -
CATEGORY - Aquatic Crustaceans
PHYLUM AND SUBPHYLUM - Crustacea,
CLASS AND SUBCLASS - Malacostraca,
ORDER AND SUBORDER - Decapoda,
FAMILY AND SUBFAMILY - Crangonidae,
GENUS AND SUBGENUS - Crangon,
SPECIES AND SSP - franciscorum,
SCIENTIFIC NAME - Crangon franciscorum
AUTHORITY -
TAXONOMY REFERENCES - 01
Taxonomy - 1 (DRAFT) - Status
Species Bay shrimp
Species Id M070016
Date 26 AUG 96
STATUS
Coded Status
Commercial
Commercial/consumption
Commercial/bait
See Comments
REFERENCES FOR STATUS - 01
COMMENTS ON STATUS -
Commercial: The bay shrimp is commercially fished (primarily with trawls)
only in San Francisco Bay, California. It once supported a larger fishery
that utilized trawls, fyke nets, and seines. It is fished mainly for use as
bait, but some is used for human consumption. Recently, annual landings for
3 Crangon species (C. franciscorum, C. nigricauda, and C. nigromaculata)
captured in San Francisco Bay have ranged from 2.3 to 25.0 t.*01*
Status - 1 (DRAFT) - Distribution
Species Bay shrimp
Species Id M070016
Date 26 AUG 96
DISTRIBUTION
Distribution - 1 HABITAT ASSOCIATIONS
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Estuarine FL. N 3
Estuarine AB. N 4
REFERENCES FOR NWI - 01
COMMENTS ON HABITAT ASSOCIATIONS -
Habitat Type: Adults are found in estuaries and offshore, intertidally down
to 183 m. Ovigerous females are found in the lower portion of estuaries and
adjacent offshore waters. Juveniles primarlily inhabit channels and flats
in the low salinity of estuaries.*01*
Substrate: Larvae are found over a variety of substrates. Juveniles and
adults occur primarily over sandy to muddy substrates.*01*
Physical/Chemical Characteristics: the bay shrimp is a euryhaline species.
Juveniles and adults are found in euhaline to oligohaline waters in Prince
William Sound, Alaska (2.2-28.3 ppt). In San Francisco Bay and Delta,
highest densities are found at salinities of 1-7%. Juveniles appear to
prefer lower salinities (<32 ppt), while ovigerous females prefer
salinities > 14.6 ppt. Juveniles and nonovigerous adults tolerate
temperatures of 5.2-21.3 degrees C.; ovigerous females perfer temps of
6.8-19.2 degrees C. Salinity and temperature influence this species'
distribution significantly. High salinities retard the movements of
juveniles to lower estuarine areas, while high temperatures in the summer
increase movements to upper estuarine areas. Low salinities probably retard
egg development and salinities < 12 ppt. may reduce larval survival.
Optimum conditions for adults are salinities of 18-20% and temperatures of
4.5-17.0 degrees C.*01*
Migrations and Movements: A "spawning migration" occurs during the
reproductive periods; adult females and males move to lower, more saline
areas of estuaries (primarily March to July). Juveniles move up estuaries
during the summer to rear in lower salinity, higher temperatures araeas. As
they grow and mature, bay shrimp move to lower, more saline areas. In the
fall and winter, many adults move to near the mouth of estuaries and
nearshore areas outside estuaries. Juveniles and adults undergo nocturnal
vertical migrations to feed. Larvae appear to be advected seaward by river
flow.*01*
ANIMAL/PLANT SPECIES ASSOCIATIONS -
Predation: The bay shrimp is an important prey for the striped bass, brown
smoothhound (Mustelus henlei), green sturgeon (A. medirostris), white
sturgeon (A. transmontanus), Pacific staghorn sculpin (Leptocottus armatus),
Pacific tomcod (Microgadus proximus), prickly sculpin (Cottus asper), sand
sole (Psettichthys melanostictus), waterfowl, habor seal (Phoca vitulina),
and the Dungeness crab (Cancer magister). *01*
Factors Influencing Populations: This species may compete with the
introduced oriental shrimp (Palaemon macrodactylus) for food and resources,
especially during drought years.*01*
REFERENCES FOR SPECIES ASSOCIATIONS - 01
Habitat Associations - 1 (DRAFT) - Food Habits
Species Bay shrimp
Species Id M070016
Date 26 AUG 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
DETRITIVORE
REFERENCES FOR TROPHIC LEVEL - 01
LIFESTAGE FOOD FOOD PART
Adult Detritus Not Specified
Adult Bivalve Molluscs Not Specified
Adult Ostracods Not Specified
Adult Copepods Not Specified
Adult Crustaceans Not Specified
REFERENCES FOR GENERAL FOOD - 01
REFERENCES FOR ADULT FOOD - 01
COMMENTS ON FOOD -
Larvae, juveniles and adults are primarily carnivorous (occassionally
detritivorous), feeding on benthic and epibenthic prey. Food habits depend
ont he shrimp's size, temperature-salinity preferences, and prey
availability.*01*
The bay shrimp feeds on mysids (Neomysis mercedis), amphipods (primarily
Corophium spp.), Ampelisca abdita, and Grandidierella japonica), bivalves
(primarily Mya arenaria, Gemma gemma, and Venerupis japonica),
foraminiferans, isopods, copepods, ostracods, gastropods, and plant
material.*01*
The bay shrimp is also susceptible to cannibalism.*01*
Food Habits - 1 (DRAFT) - Environment Associations
Species Bay shrimp
Species Id M070016
Date 26 AUG 96
ENVIRONMENTAL ASSOCIATIONS
G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae
FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
A Water Temperature: Below 15 degrees C
A Water Temperature: Between 15-21 degrees C
A Water Temperature: Specified in Comments
A
A
A
A Substrate: Sand
A Substrate: Mud or silt
A Substrate: Specified in Comments
A Relation to Substrate: Occurs on substrate [not penetrating]
A Relation to Substrate: Unattached - normally free living
A Relation to Substrate: Specified in Comments
A Bottom Type [Aquatic]: Mud or silt
A Bottom Type [Aquatic]: Sand
A Water Depth Preference: Less than 1 ft.
A Water Depth Preference: 1-5 ft.
A Water Depth Preference: 5-10 ft.
A Water Depth Preference: 10-25 ft.
A Water Depth Preference: 25-50 ft.
A Water Depth Preference: 50-100 ft.
A Water Depth Preference: 100-200 ft.
A Water Depth Preference: 200-500 ft.
A Water Depth Preference: 500-1000 ft.
A Water Depth Preference: Specified in Comments
A Estuarine habitat zone: bay
A Estuarine habitat zone: sound
A Estuarine habitat zone: offshore
A Estuarine habitat zone: specified in comments
A Currents: specified in comments
L
LIM
REFERENCES FOR LIMITING ENVIRONMENTAL ASSOC_ - 01
REFERENCES FOR ADULT ENVIRONMENTAL ASSOC_ - 01
REFERENCES FOR LARVAE ENVIRONMENTAL ASSOC_ - 01
Environment Associations - 1 (DRAFT) - Environment Associations
Species Bay shrimp
Species Id M070016
Date 26 AUG 96
COMMENTS ON ENVIRONMENTAL ASSOCIATIONS -
Habitat Type: Adults are found in estuaries and offshore, intertidally down
to 183 m. Ovigerous females are found in the lower portion of estuaries and
adjacent offshore waters. Juveniles primarlily inhabit channels and flats
in the low salinity of estuaries.*01*
Substrate: Larvae are found over a variety of substrates. Juveniles and
adults occur primarily over sandy to muddy substrates.*01*
Physical/Chemical Characteristics: the bay shrimp is a euryhaline species.
Juveniles and adults are found in euhaline to oligohaline waters in Prince
William Sound, Alaska (2.2-28.3 ppt). In San Francisco Bay and Delta,
highest densities are found at salinities of 1-7%. Juveniles appear to
prefer lower salinities (<32 ppt), while ovigerous females prefer
salinities > 14.6 ppt. Juveniles and nonovigerous adults tolerate
temperatures of 5.2-21.3 degrees C.; ovigerous females perfer temps of
6.8-19.2 degrees C. Salinity and temperature influence this species'
distribution significantly. High salinities retard the movements of
juveniles to lower estuarine areas, while high temperatures in the summer
increase movements to upper estuarine areas. Low salinities probably retard
egg development and salinities < 12 ppt. may reduce larval survival.
Optimum conditions for adults are salinities of 18-20% and temperatures of
4.5-17.0 degrees C.*01*
Migrations and Movements: A "spawning migration" occurs during the
reproductive periods; adult females and males move to lower, more saline
areas of estuaries (primarily March to July). Juveniles move up estuaries
during the summer to rear in lower salinity, higher temperatures araeas. As
they grow and mature, bay shrimp move to lower, more saline areas. In the
fall and winter, many adults move to near the mouth of estuaries and
nearshore areas outside estuaries. Juveniles and adults undergo nocturnal
vertical migrations to feed. Larvae appear to be advected seaward by river
flow.*01*
COMMENTS ON LIMITING ENVIRONMENTAL ASSOC_ -
Low salinities probably retard egg development and salinities < 12 ppt. may
reduce larval survival.
Environment Associations - 2 (DRAFT) - Life History
Species Bay shrimp
Species Id M070016
Date 26 AUG 96
LIFE HISTORY
Reproduction
Mode: The bay shrimp is gonochoristic and oviparous. Sperm is stored
internally in the female; eggs are fertilized when extruded and brooded
externally on the female's body.*01*
Mating/Spawning: Although gravid females may be found year-round, usually
only two spawning periods exist (sometimes only one depending on the
estuary). In Yaquina Bay Oregon, spawning occurs from December to March
(older females), and from April to August (first-time and repeat spawners).
The second spawning is usually larger (more spawners present for a longer
period) than the first. In San Francisco Bay, only a single extended
spawning period was thought to exist, with a peak from March to September.
However, a bimodal reproductive schedule appears to occur here also; during
the first period, gravid females reside primarily off the mouth of San
Francisco Bay. A "spawning migration" occurs with females and males moving
to deeper, higher salinity areas (usually >21 ppt), depending on water
temperature) when they become reproductively active. Nearshore areas outside
of estuaries are often used by spawning adults during the winter and spring.
*01*
Fecundity: Females from 47.8-67.4 mm total length (TL) carried 1,923-4,764
eggs per female, with a mean of 3,528. Fecundity of bay shrimp ranged from
1,977-3,103 in Gray's Harbor, Wa., and from 2,499-8,840 in south San
Francisco Bay. Fecundity (Y) was calculated to be Y=-5338.7+156.1 TL for
shrimp in Yaquina Bay, and log Y=-3.66+4.09log(TL) for shrimp in San
Francisco Bay.*01*
Growth and Development:
Egg size and Embryonic Development: Eggs are spherical and 0.60 in diameter.
Embryonic development is indirect and external; eggs remain in the female's
brood pouch until hatching. Eggs appear to take 8-12 weeks to mature,
depending on temperature. Larvae hatched in early spring develop into
juveniles by May to July.*01*
Age and Size of Larvae: Larvae range from 6.0-7.4 mm TL. Larvae undergo 7
larval stages in 21 days at 17.5 degrees C.*01*
Juvenile Size Range: Juvenile bay shrimp range from 6.0-7.4 mm to about 34
mm TL for males, 48 mm TL for females, however, this may differ between
estuaries. After reaching 30 mm TL, growth is estimated to be 2.0 mm/month.
*01*
Age and Size of Adults: Both sexes mature in about 1-1.5 years, with most
males reaching maturity at 34 mm TL and females at 48 mm TL or 55-60 mm TL
in San Francisco Bay. Males appear to spawn only once, while females may
produce 2 broods. Females are 60 mm TL in 1.5 years, males 50-52 mm TL after
1 year; females > 62 mm TL are rare in Yaquina Bay, but are common off the
Columbia River. The largest size reported is 110 mm TL off the Columbia
River. Females may live 2-2.5 years and males about 1.5 years.*01*
Life History - 1 (DRAFT) - Life History
Species Bay shrimp
Species Id M070016
Date 26 AUG 96
LIFE HISTORY CODES -
Foraging Sites: Standing water - Littoral zone
Breeding/Spawning Season: January
Breeding/Spawning Season: February
Breeding/Spawning Season: March
Breeding Spawning Season: April
Breeding/Spawning Season: May
Breeding/Spawning Season: June
Breeding/Spawning Season: July
Breeding/Spawning Season: August
Breeding/Spawning Season: September
Breeding/Spawning Season: November
Gestation/Incubation Period: 3-4 months
Gestation/Incubation Period: 1-2 months
Average Number of Offspring/Reproductive Effort: 1,00
Parental Care of Young: No care given young
Dispersion: Other (specify in comments)
Periodicity: Other (specify in comments)
REFERENCES FOR LIFE HISTORY- 01
Life History - 2 (DRAFT) - Management Practices
Species Bay shrimp
Species Id M070016
Date 26 AUG 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial
Beneficial Controlling pollution [thermal, chemical, physical]
Adverse Wastewater disposal/assimilation
Adverse Bilge purging/cleaning
Adverse Changing tidal cycle/ current patterns
Adverse Applying other toxicants
Adverse Salinity alteration
Beneficial Other management practices [specified in comments]
REFERENCES FOR BENEFICIAL MANAGEMENT PRACTICES - 01
REFERENCES FOR ADVERSE MANAGEMENT PRACTICES - 01
COMMENTS ON MANAGEMENT PRACTICES -
Factors Influencing Populations: This species may compete with the
introduced oriental shrimp (Palaemon macrodactylus) for food and resources,
especially during drought years. The bay shrimp is one of the most abundant
organisms entrained during dredging operations in Pacific Northwest
estuaries. Its distribution is also influenced by the availability and
abundance of the mysid Neomysis mercedis. Freshwater inflow into estuaries
strongly influences this species distribution and abundance. Abiotic
conditions during winter and spring off the mouths of estuaries may also
influence populations. The bay shrimp is a short-lived species that shows
large annual fluctuations in abundance and may be highly sensitive to
effects of short-term estuarine pollution.*01*
Management Practices - 1 (DRAFT) - References
Species Bay shrimp
Species Id M070016
Date 26 AUG 96
References
01 Emmett, R. L., S. L. Stone, S. A. Hinton, and M. E. Monaco. 1991
Distribution and abundance of fishes and invertebrates in west coast
estuaries, Volume II: species life history summaries. ELMR Rep. No. 8.
NOAA/NOS Strategic Environmental Asessments Division, Rockville, MD,
329p.
References - 1