(DRAFT) - Taxonomy
Species cod, Pacific
Species Id M010594
Date 27 AUG 96
TAXONOMY
NAME - cod, Pacific
OTHER COMMON NAMES -
ELEMENT CODE -
CATEGORY - Fish
PHYLUM AND SUBPHYLUM - ,
CLASS AND SUBCLASS - ,
ORDER AND SUBORDER - ,
FAMILY AND SUBFAMILY - ,
GENUS AND SUBGENUS - Gadus,
SPECIES AND SSP - macrocephalus,
SCIENTIFIC NAME - Gadus macrocephalus
AUTHORITY - Tilesius
TAXONOMY REFERENCES - 232
Taxonomy - 1 (DRAFT) - Status
Species cod, Pacific
Species Id M010594
Date 27 AUG 96
STATUS
Coded Status
Migrant
Existing, FMP exists
See Comments
REFERENCES FOR STATUS - 232
COMMENTS ON STATUS -
Pacific cod within the 200-mi limit are managed by the North Pacific Fishery
Management Council (NPFMC) through their groundfish fishery management plans
*232*.
Pacific cod follow short (300 to 500 km) seasonal migrations *232*.
Status - 1 (DRAFT) - Distribution
Species cod, Pacific
Species Id M010594
Date 27 AUG 96
DISTRIBUTION
Distribution - 1 HABITAT ASSOCIATIONS
HABITAT - MARINE
REFERENCES FOR HABITAT - 232
LAND USE -
Water
REFERENCES FOR LAND USE - 232
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Marine
REFERENCES FOR NWI - 232
COMMENTS ON HABITAT ASSOCIATIONS -
Pacific cod are mostly benthic and are found at depths ranging from 15 to
550 m. In the Bering Sea, age 0 (less than one year) cod are found in
coastal waters. As the fish grow they move to progressively deeper, less
coastal water, with age 1 fish found in inner continental shelf waters, age
2 and 3 on the central shelf, and age 4 and older on the outer shelf *232*.
ANIMAL/PLANT SPECIES ASSOCIATIONS -
Halibut (Hippoglossus stenolepis)
Fur seal (Callorhinus ursinus)
Belukha whale (Delphinapterus leucas)
Sperm whale (Physeter macrocephalus)
REFERENCES FOR SPECIES ASSOCIATIONS - 232
COMMENTS ON SPECIES ASSOCIATIONS -
Little information is available on predators of Pacific cod; however,
halibut (Hippoglossus stenolepis), fur seals (Callorhinus ursinus), belukha
whales (Delphinapterus leucas), and sperm whales (Physeter macrocephalus)
have all been reported to feed on gadoids (cods) *232*.
Habitat Associations - 1 (DRAFT) - Food Habits
Species cod, Pacific
Species Id M010594
Date 27 AUG 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
REFERENCES FOR TROPHIC LEVEL - 232
LIFESTAGE FOOD FOOD PART
Adult Osteichthyes Not Specified
General Osteichthyes Not Specified
Adult Crustaceans Not Specified
General Crustaceans Not Specified
Adult Malacostraca Not Specified
General Malacostraca Not Specified
General Perciformes Not Specified
General Clupeiformes Not Specified
General Gadiformes Not Specified
General Invertebrate Cordates Not Specified
General Copepods Not Specified
General See Comments; Food Not Specified
Adult See Comments; Food See Comments
Juvenile Copepods Not Specified
Juvenile See Comments; Food See Comments
REFERENCES FOR GENERAL FOOD - 232
REFERENCES FOR ADULT FOOD - 232
REFERENCES FOR JUVENILE FOOD - 232
COMMENTS ON FOOD -
Studies from the southeastern and Kodiak areas of the Gulf of Alaska found
that fish, crabs, and shrimp were the major foods of adult cod in those
areas. In the Kodiak area, the fish most frequently found in cod stomachs
was walleye polluck (Theragra chalcogramma). Flatfishes (Pleuronectidae)
and Pacific sand lance (Ammodytes hexapterus) were also commonly found. In
the southeastern gulf, Pacific herring (Clupea harengus pallasi) and walleye
pollock were eaten most oftern. In both areas, Tanner crab (Chionoecetes
bairdi) was the most commonly consumed crab. Cod in outside waters eat a
larger volume of crabs than those in inside waters and, conversely, that cod
in inside waters eat a higher volume of shrimp (especially pandalid shrimp)
and more fish (especially Pacific herring) than cod in outside waters. A
1980 Northwest and Alaska Fisheries Center (NWAFC) study reproted that in
the Bering Sea pollock, shrimp, other invertebrates, and Tanner crab were
most frequently found in cod stomachs. Some variation in food habitat by
region was also noted. In Bristol Bay, the principal food item was Tanner
crab; in the central Bering Sea, pollock, Tanner crab, and other
invertebrates; and in the northern Bering Sea, shrimp and pollock. Young
cod feed on copepods and similar organisms *232*.
Types of Feeding Areas Used: In the western Bering Sea and the Sea of
Okhotsk cod migrate to shallow waters in search of food in early spring.
Food Habits - 1 (DRAFT) - Food Habits
Species cod, Pacific
Species Id M010594
Date 27 AUG 96
Cod in other areas also follow short seasonal migratory patterns, spawning
in relatively deep water and moving to more shallow water while feeding in
the spring *232*.
Feeding Behavior: Pacific cod do not feed during spawning. They are
apparently somewhat opportunistic feeders; the abundance of preferred prey
items in their stomachs varies with the abundance of those prey items in the
environment *232*.
COMMENTS ON ADULT FOOD -
Studies from the southeastern and Kodiak areas of the Gulf of Alaska found
that fish, crabs, and shrimp were the major foods of adult cod in those
areas *232*.
COMMENTS ON JUVENILE FOOD -
Young cod feed on copepods and similar organisms *232*.
Food Habits - 2 (DRAFT) - Environment Associations
Species cod, Pacific
Species Id M010594
Date 27 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
G Aquatic Habitat Zonation: Open water [pelagic zone]
G Aquatic Habitat Zonation: Specified in Comments
G Water Depth Preference: 25-50 ft.
G Water Depth Preference: 50-100 ft.
G Water Depth Preference: 100-200 ft.
G Water Depth Preference: 200-500 ft.
G Water Depth Preference: 500-1000 ft.
G Water Depth Preference: 1000-1500 ft.
E Water Temperature: Specified in Comments
E
E Dissolved Oxygen: Specified in Comments
BA Water Depth Preference: Specified in Comments
FA Water Depth Preference: Specified in Comments
BA Water Depth Preference: 200-500 ft.
BA Water Depth Preference: 500-1000 ft.
BA Water Depth Preference: 25-50 ft.
BA Water Depth Preference: 50-100 ft.
BA Water Depth Preference: 100-200 ft.
BA Water Temperature: Below 15 degrees C
BA Water Temperature: Specified in Comments
E Water Depth Preference: Specified in Comments
L Water Depth Preference: 50-100 ft.
L Water Depth Preference: 100-200 ft.
L Water Depth Preference: 200-500 ft.
L Water Depth Preference: Specified in Comments
L Water Temperature: Below 15 degrees C
L Water Temperature: Specified in Comments
REFERENCES FOR ENVIRONMENTAL ASSOC_ - 232
REFERENCES FOR FEEDING ADULT ENVIRONMENTAL ASSOC_ - 232
REFERENCES FOR BREEDING ADULT ENVIRONMENTAL ASSOC_ - 232
REFERENCES FOR LARVAE ENVIRONMENTAL ASSOC_ - 232
REFERENCES FOR EGG ENVIRONMENTAL ASSOC_ - 232
Environment Associations - 1 (DRAFT) - Environment Associations
Species cod, Pacific
Species Id M010594
Date 27 AUG 96
COMMENTS ON ENVIRONMENTAL ASSOCIATIONS -
Water Depth: Pacific cod are mostly benthic and are found found at depths
ranging from 15 to 550 m. Research vessel surveys carried out in the Gulf
of Alaska from summer 1980 to late winter 1982 found that the highest
Pacific cod density was in the 51 to 100 m depth interval. Their depth
distribution varies, however, with the location of the stock and the time
of year *232*.
Water Temperature: Water temperature is very important to the hatching
success and survival of cod eggs and may in that way determine the limits
of Pacific cod distribution. Survival drops off more rapidly in
temperatures below optimum than in temperatures above optimum. Optimal
larval survival was found to be 7 to 8 oC *232*.
Water Chemistry: Eggs are tolerant of a wide range of oxygen and salinity
levels. If temperatures are within the optimum range, eggs tolerate
dissolved oxygen levels from saturation down to 2-3 ppm and salinities from
at least 12.71 to 23 o/oo *232*.
COMMENTS ON BREEDING ADULT ENVIRONMENTAL ASSOC_ -
Reproductive Habitat: Cod generally migrate to relatively deep water (80
to 290 m) to spawn. An exception to this is in the southern part of their
Asian range, where the cod move inshore to spawn in waters 15 to 50 m deep.
Location of spawning is probably more closely correlated to water
temperature than to depth. Spawning is probably inhibited at temperatures
above 9 oC or below 0 oC. Spawning usually occurs in the western Bering Sea
at depths of 100 to 250 m and at temperatures of 0 to 3 oC *232*.
COMMENTS ON LARVAE ENVIRONMENTAL ASSOC_ -
Optimal larval survival was found to be 7 to 8 oC *232*.
Larvae are found in coastal areas at depths of 25 to 150 m, with the
majority occurring between 75 to 100 m *232*.
COMMENTS ON EGG ENVIRONMENTAL ASSOC_ -
Water Chemistry: Eggs are tolerant of a wide range of oxygen and salinity
levels. If temperatures are within the optimum range, eggs tolerate
dissolved oxygen levels from saturation down to 2-3 ppm and salinities from
at least 12.71 to 23 o/oo *232*.
Water Temperature: Water temperature is very important to the hatching
success and survival of cod eggs and may in that way determine the limits
of Pacific cod distribution. Survival drops off more rapidly in
temperatures below optimum than in temperatures above optimum *232*.
Pacific cod eggs are demersal (develop on the ocean floor). The rate of
development is affected by temperature. Hatching takes place in 11.5 days
at 8 oC, but about 28 days are needed for hatching at 2 oC *232*.
Environment Associations - 2 (DRAFT) - Life History
Species cod, Pacific
Species Id M010594
Date 27 AUG 96
LIFE HISTORY
Reproductive Habitat: Cod generally migrate to relatively deep water (80
to 290 m) to spawn. An exception to this is in the southern part of their
Asian range, where the cod move inshore to spawn in waters 15 to 50 m deep.
Location of spawning is probably more closely correlated to water
temperature than to depth. Spawning is probably inhibited at temperatures
above 9 oC or below 0 oC. Spawning usually occurs in the western Bering Sea
at depths of 100 to 250 m and at temperatures of 0 to 3 oC *232*.
Reproductive Seasonality: Spawning takes place during the winter months.
In Canadian coastal waters, spawning takes place from January to March. In
the eastern Bering Sea, spawning probably takes place from January to April
*232*.
Age at Sexual Maturity: In British Columbia waters, male cod mature at age
2 (49 cm in length). At age 3 ( 55 cm), 50% of female cod are mature.
Female Pacific cod in the eastern Bering Sea apparently reach maturity at a
length greater than 65 cm *232*.
Frequency of Breeding: Cod breed annually *232*.
Fecundity: Fecundity increases with the size of the fish. A 55-cm female
off British Columbia will produce about 860,000 eggs, whereas an 80-cm
female will produce about 3,350,000 eggs. The length-fecudnity relationship
for cod in Asian waters (Sakhalin and West Kamachatka) was the same as that
for cod in British Columbia waters *232*.
Incubation Period: Pacific cod eggs are demersal (develop on the ocean
floor). The rate of development is affected by temperature. Hatching takes
place in 11.5 days at 8 oC, but about 28 days are needed for hatching at 2
oC. Larvae are found in coastal areas at depths of 25 to 150 m, with the
majority occurring between 75 to 100 m. Larvae (8.8 to 11.6 mm in length)
have been found in Bering Sea plankton in June and July and in Cook Inlet
(5.3 to 9.0 mm in length) in May and July. Larvae of unspecified lengths
were found in Kodiak bays in April and May and in March-April and June-July
on the Kodiak shelf *232*.
Movements Associtated with Life Functions: In the Bering Sea, age 0 (less
than one year) cod are found in coastal waters. As the fish grow they move
to progressively deeper, less coastal water, with age 1 fish found in inner
continental shelf waters, age 2 and 3 on the central shelf, and age 4 and
older on the outer shelf. Pacific cod follow short (300 to 500 km) seasonal
migrations. Generally they move into deeper (110 to 128 m) waters to spawn
in late winter (January to April). After spawning, the movement is
generally into more shallow (37 to 55 m) areas. The extent and direction of
these migrations are probably controlled more by temperature and location of
food than by depth *232*.
Natural Factors Influencing Populations: Little information is available on
predators of Pacific cod; however, halibut (Hippoglossus stenolepis), fur
seals (Callorhinus ursinus), belukha whales (Delphinapterus leucas), and
sperm whales (Physeter macrocephalus) have all been reported to feed on
Life History - 1 (DRAFT) - Life History
Species cod, Pacific
Species Id M010594
Date 27 AUG 96
gadoids (cods). Ocean currents and weather patterns that carry larvae into
productive areas and that result in a concentration of plankton are probably
important for survival of cod larvae *232*.
Human-related Factors Influencing Populations: A summary of possible
impacts from human-related activities includes: alteration of preferred
water temperatures, pH, dissolved oxygen, and chemical composition;
introduction of water-soluble substances; increase in suspended organic or
mineral material; reduction in food supply; human harvest; and seismic shock
waves *232*.
LIFE HISTORY CODES -
Breeding/Spawning Season: January
Breeding/Spawning Season: February
Breeding/Spawning Season: March
Breeding Spawning Season: April
Number of Broods/Litters (Reproductive Efforts) Per Ye
Average Number of Offspring/Reproductive Effort: Grea
REFERENCES FOR LIFE HISTORY- 232
Life History - 2 (DRAFT) - Management Practices
Species cod, Pacific
Species Id M010594
Date 27 AUG 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Developing/maintaining suitable salinity
Beneficial Developing/maintaining suitable pH
Adverse Salinity alteration
Beneficial Prohibiting harvest of species being described
Beneficial Other management practices [specified in comments]
Adverse Other management practices [specified in comments]
REFERENCES FOR BENEFICIAL MANAGEMENT PRACTICES - 232
REFERENCES FOR ADVERSE MANAGEMENT PRACTICES - 232
COMMENTS ON MANAGEMENT PRACTICES -
Human-related Factors Influencing Populations: A summary of possible
impacts from human-related activities includes: alteration of preferred
water temperatures, pH, dissolved oxygen, and chemical composition;
introduction of water-soluble substances; increase in suspended organic or
mineral material; reduction in food supply; human harvest; and seismic shock
waves *232*.
Pacific cod within the 200-mi limit are managed by the North Pacific Fishery
Management Council (NPFMC) through their groundfish fishery management plans
*232*.
Management Practices - 1 (DRAFT) - References
Species cod, Pacific
Species Id M010594
Date 27 AUG 96
References
232 * State of Alaska Department of Fish, and Game. 1986. Alaska
Habitat Management Guide: Life Histories and Habitat
Requirements of Fish and Wildlife. (ed.). Alaska Department of
Fish and Game Juneau, Alaska:763.
References - 1