ECOLOGICAL DATA
Distribution: B.C. coast is the center of abundance of
Pacific herring for North America.
Habitat: mature adults leave offshore feeding grounds off mouth of Juan de Fuca
Strait in south and in Hecate Strait in north, during Oct-Dec and migrate to inshore
spawning areas; remain inshore in deep channels and bays near spawning areas to complete
maturation; spawning peaks in Mar in south coast, late Mar to mid-Apr in north coast and
Queen Charlotte Islands; very early and late spawners are resident inshore stocks; spawn
on intertidal and subtidal vegetation, including filamentous and branching red algae, sea
grasses, rockweed kelp,and other brown algae; eggs adhere to vegetation and fertilized
externally; eggs hatch simultaneously in 10-21 days; 9 mm larvae live on yolk sac for
about 6 d and then feed on plankton; currents tend to concentrate larvae in the surface
layer near shore; juveniles undergo diel migrations, deep during day and shallow during
darkness; during summer form large schools in protected waters of bays and inlets near
spawning areas; in Sep gradually move seaward to feeding grounds, depth 150-200 m;
immatures (2nd yr) tend to intermingle with juveniles and adults, depth of 100-150 m;
adults in same offshore feeding grounds, depth 100-150 m; return to feed in Apr and May
after spawning; some small resident populations remain inshore near spawning areas all
year.
Tidal elevation: spawn from high tide to 20 m subtidal depth, and generally
within a 150 m wide strip.
Food:larvae feed on invertebrate eggs, copepods, diatoms; feed on larger
zooplanton as they grow; adults eat larger forms of crustaceans and small fish; cease
feeding during winter prior to spawning; adults also may filter feed when other food is
unavailable.
Predators: gulls and diving ducks eat eggs; pilchards, ctenophores and jelly
fish prey on larvae; gulls, diving ducks, fishes and marine mammals prey on adults,
especially during spawning.
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GROWTH RATE
Larvae are 9-25 mm; juveniles range from 25-100 mm at end of
1st year; sexually mature 3 yr, 180 mm; most adults 175-250 mm and 3-6 yr; maximum size
age is 340 mm at 15 yr.
FISHERY
Valuable commercial fishery (2nd only to salmon), 16,341 t
valued at $40 million, and spawn on kelp of 150 t valued at $6.4 million in 1986; native
fishery and bait fishery for salmon sport fishing.
REFERENCES
Anon. 1983. The Pacific herring. Underwater World, Dep. Fish.
Oceans Can., Ottawa: 6 p.
Haegele, C.W., and J.F. Schweigert. 1985. Distribution and characteristics of herring
spawning grounds and description of spawning behavior. Can. J. Fish. Aquat. Sci. 42
(Suppl. 1): 39-55.
Hart, J.L. 1973. Pacific fishes of Canada. Fish. Res. Board Can. Bull. 180: 96-100.
Hay, D.E. 1985. Reproductive biology of Pacific herring (Clupea harangus pallasi).
Can. J. Fish. Aquat. Sci. 42 (Suppl. 1): 111-126.
Hourston, A.S., and C.W. Haegele. 1980. Herring on Canada's Pacific coast. Can. Spec.
Publ. Fish. Aquat. Sci. 48: 23 p.
Humphreys, R.D., and A.S. Hourston. 1978. British Columbia herring spawn deposition
survey manual. Fish. Mar. Serv. Misc. Spec. Publ. 38: 40 p.
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