Common names
Longjaw rockfish (BC fishermen)
Andy-gump (BC fishermen)
Rock salmon
Salmon rockfish
Pacific red snapper
Pacific snapper
Oregon snapper
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Range
Bocaccio is found throughout the coastal waters of the eastern Pacific Ocean from the Gulf of Alaska south to Baja California Mexico.
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Habitat and Distribution
In BC, bocaccio are mainly caught along the outer Pacific coast near the edge of the continental shelf, with largest catches from the northwest end of Vancouver Island and Queen Charlotte Sound. They are sometimes reported from mainland inlets as well as the Strait of Georgia. The depth of catch is slightly shallower during summer than winter, with median depth of catch in the trawl fishery of 110 m in summer to 180 m in winter. Two tagging studies conducted off the coast of California suggest that bocaccio move more during the first few years of life, and become more sedentary as they age. The amount of movement appears to drop off after they reach a length of 47 cm.
Boccacio rockfish commercial fishery catch distribution map is linked below:
The seasonal depth distribution of bocaccio rockfish catch in the BC bottom trawl fishery from 1996 to 2003 is shown below.
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Reproduction
Bocaccio bear live young and produce between 20,000 and 230,000 eggs. Fecundity tends to increase with increasing size of a female. Copulation occurs early in the fall and larval release occurs over the winter. The larvae are 4 - 5 mm in length at parturition and metamorphose into pelagic juveniles at 19 - 40 mm over a period of several months. The growth of juveniles is rapid at around 0.56 - 0.97 mm per day. They can reach 24 cm in length by the end of the first year. The
juveniles settle into littoral and demersal habitat from late spring throughout the summer. Young-of-the-year live near the surface for a few months and then settle in nearshore areas where they form schools over bottom depths of 30 - 120 m. Adults may be semi-pelagic and are found over a variety of bottom types between bottom depths of 60 - 300 m.
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Growth
Female boccacio are known to grow to a larger size than males. However, boccacio are difficult to age and quantitative information on growth is not available. The maximum recorded size is 91 cm for males, and 75 cm for females. The maximum reported weight is 6.8 kg.
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Maturity
Bocaccio are thought to mature around 4 to 5 years of age.
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Longevity and Mortality
Bocaccio are difficult to age and thus the maximum age of bocaccio is unknown but radiometric dating of the ear bones has suggested a maximum of 50 years. Little is known about the mortality of younger ages. Estimates of the natural mortality rate vary between 14 - 22 % per year. This implies that it would take between 12 – 20 years for 95% of fish of the same age to die of natural causes. Age-at-maturity and maximum age imply a generation time of about 10 years.
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Diet
Juvenile bocaccio feed on larvae, euphausiids, young rockfish, surf perch, mackerel and numerous small inshore fishes. Adults feed on other rockfish, sablefish, anchovies, lanternfish and squid.
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Predators
The main predators of juvenile bocaccio are seabirds including the least tern. The main predators of adults are marine mammals such as harbour seals and northern elephant seals.
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Fishery
In BC, bocaccio are commonly caught along with several other groundfish species including Pacific ocean perch, yellowtail rockfish and canary rockfish. In recent years, their occurrence appeared to be relatively predictable in both time and space. Current commercial catches are low, as are the sport and First Nations catches. They currently make up less than 1% of the commercial trawl landings, but there is a small amount of targeting for boccacio. Commercial trawl catch is almost zero in the Strait of Georgia . There is a small hook-and-line catch as well as discarding in the commercial hook-and-line fisheries for halibut, ZN and Schedule II. The populations in BC are contiguous with those in Washington State ; therefore it is possible that catches in the US may impact the BC populations. At this time however, this is unlikely to be an issue as US landings are very low due to restrictive trip limits.
Boccacio are caught at depths between 60-340 m during bottom trawling while midwater trawl catches tend to occur over bottom depths of 60-200 m. Incidental catches in midwater trawling occur when yellowtail (Sebastes flavidus) and widow rockfish (S. entomelas) are targeted in the fishery.
Most of the BC catch occurs off the west coast of Vancouver Island and in Queen Charlotte Sound with minimal catches occurring in Hecate Strait and off the west coast of Haida Gwaii. Landings were high in the late 1980s and early 1990s but have declined significantly since that time, and are currently lower, but stable.
The reported catch of bocaccio rockfish in the BC bottom trawl fishery by trawl management area is shown below.
A management plan based on individual vessel quotas (IVQs) was introduced for the BC trawl fishery in 1997. Bocaccio catches are not limited by IVQs but are constrained by a 15,000 lb trip limit for all non-quota rockfish combined. The 2004/05 landed value of the Bocaccio fishery is $230,000.
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Population Trends
The abundance of Bocaccio in BC waters is unknown. There is little directed research because of its lack of commercial importance. The population as a whole is present in all coastal waters along the edge of the continental shelf. The abundance in the outer North Coast is unknown but it appears to be stable in the Central Coast.
The US National Marine Fisheries Service (NMFS) conducts triennial surveys and operated 7 times in Canadian waters between 1980-2001. These surveys led to conclusions that bocaccio biomass has declined in the Vancouver INPFC region although there have been some problems using this biomass index to determine trends in abundance. Another index is derived from the WCVI shrimp trawl survey that has been carried out every year since 1973 and has recorded rockfish catches since 1975. This survey represents the longest series of biomass estimates for bocaccio in Canadian waters and has shown that there was relatively low biomass in the 1970s, increasing in the mid 1980s and declining by the late 1980s, a trend that has continued to the present. Again, like the NMFS survey estimates, these estimates have low precision. However, there does appear overall to be some evidence of a decline over the last two decades in southern offshore waters, and there is strong evidence for a similar decline in US waters further south.
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References
Love, M.S., M. Yoklavich, and L. Thorsteinson 2002. The Rockfishes of the Northeast Pacific. Berkeley, CA , University of California Press, 405 pp.
Stanley, R.D., Starr, P. and N. Olsen 2004 Bocaccio Update. DFO Science Advisory Secretariat Research Document 2004/027. 64 pp.
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