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Goose Barnacle (crabs per km2) and habitat area (km2) estimated using a GIS. These estimates are Goose barnacle (Pollicipes polymerus) attach then adjusted using the CPUE for each area. themselves by flexible stalks in dense Two area-swept trawl surveys have been clusters on mid rocky intertidal shores completed; central west coast of Vancouver exposed to high wave action. Life history of Island (Nootka region) in 1999 and Queen goose barnacles in British Columbia has Charlotte Sound and West Coast of Haida been recently reviewed by Lauzier (1999 a). Gwaii in 2000. Approximately 40% of the coast has been covered by the industry trap Landings for goose barnacle are recorded survey. At present, DFO is working with once from PFMA 1 (1994) and three times in industry to complete the trap survey. PFMA 2 (2E + 2W) between 1988 and 1993. Where the trap survey has been completed, Total landings from all areas in all years DFO is initiating an experimental fishery to were <10 t. As with king crab, these were assess population responses to fishing and exploratory fisheries and there has been no validate biomass estimates (Workman et al. further fishing since 1994. The fishery is 2000). The current experimental fishery is presently closed in British Columbia. operating off the northwest coast of Vancouver Island in PFMA 125. Tanner Crabs In summer 2000, exploratory sounding, Tanner crab (Chionoecetes tanneri and C. trawling and trapping was undertaken in angulatus) are deep-water continental shelf the deep continental slope waters off Queen and slope predatory species. There are Charlotte Sound and the West Coast of established fisheries for Chionoecetes species Haida Gwaii. Survey objectives were to in Alaska and in eastern Canada where they identify potential Tanner crab habitat, are called “snow” crab. The life history of conduct experimental trawling and Tanner crab is little known from British trapping for distribution and abundance Columbia waters. data and collect general species biodiversity data from these unfished depths. Fisheries and Oceans Canada began Commercial fishing has taken place in these investigating the commercial potential of areas previously, but at much shallower Tanner crab (Chionoecetes tanneri and C. depths. Trawling and trapping (at 500 to angulatus) with a literature review and 1900 m depth – Figure 31) was executed development of an exploratory assessment with a large shrimp trawl (fitted with a program in 1997. Assessment and small-mesh cod-end liner to retain animals development of a possible future to 10 mm length) or with baited conical top- commercial fishery on these species is loading traps. In traps, crabs dominated the occurring under the science advisory catch with fewer than a dozen species framework (Perry et al. 1999) for new and encountered as by-catch, conversely, in developing invertebrate fisheries (J. trawls >140 taxa were captured in Boutillier and G. Workman, DFO, personal association with crabs. Each set’s catch was communications). Two sources of data are sorted to species and weighed, enabling the required to assess Tanner crab; area-swept identification of all animals. For all species trawl density data collected by DFO and of crab, size, weight, maturity state, and distributional trap Catch Per Unit Effort shell condition were recorded for use in (CPUE) data collected by industry stock assessments and in life history studies. participants. Biomass estimates are Deep sampling yielded increased catches of calculated using the trawl density data C. angulatus and two other little known deep water crab species, Paralomus verrilli 110 111 and P. multispina. Sufficient numbers of P. Sea Cucumber verrilli and P. multispina were caught to provide the first basic population data ever The red sea cucumber (Parastichopus collected for these species in British californicus) is a large species (to 45 cm Columbia. At depths >1500m P. verilli length) found from the lowest intertidal dominated, from 1000 to 1500 m depth C. zone to over 100 m depth on a wide range angulatus and P. multispina dominated, and of rocky to sandy habitats of moderate to at depths <1000 m C. tanneri and P. low exposure. It uses a ring of cauliflower- multispina were most abundant. Tanner like tentacles at the anterior end of its crab (C. tanneri) were less abundant off cucumber-shaped body to mop up Haida Gwaii than off the West Coast of deposited material. Sea cucumbers digest Vancouver Island. Significant quantities of the organic components of ingested C. angulatus, however, occupy the deeper sediments and void the indigestible depths off Haida Gwaii. The preliminary components. The life history of this species invertebrate species biodiversity data (»70 is poorly known (Boutillier et al. 1998). taxa) were contributed to the database in Appendix D and the full cruise results will Commercial fishers dive to collect sea be reported by Workman et al. (2000, in cucumbers by hand. Catch weight is preparation). reported “split” (de-watered and gutted). Products are boiled body walls for export to Green Sea Urchin Asia and muscle strips from inside the body walls for both export and domestic Green sea urchin (Strongylocentrotus consumption. The management of this droebachiensis) is a circumpolar, arctic-boreal fishery is covered in detail the Integrated species whose life history is particularly Fishery Management Plan, so only a Haida well studied in the north Atlantic. It is a Gwaii area overview is provided. smaller species than the red sea urchin, but is also a herbivorous grazer on attached and The first landings of sea cucumber from drift seaweed. Fishing is by divers and the Haida Gwaii started in 1987 from PFMA 2E commercial product is sea urchin roe. As and 2W. From 1987 through 1995, PFMA with red sea urchin, sea otters are known to 2W reported total landings of three t split reduce green sea urchin populations in weight from two years of fishing whereas Alaska and British Columbia (Watson and PFMA 2E averaged 42.5 t annually from Smith 1996). nine years of fishing. Since 1996, Haida Gwaii has been closed to fishing due, in The fishery in Haida Gwaii has been small part, to low market value and processing with exploratory landings from PFMA 1 in logistics rendering this area economically 1989 and 1990 and PFMA 2E in 1990 only. marginal. The other reason is that sea Combined north coast (PFMAs 1 to 10) cucumber is the target of the first shellfish landings between 1987 to 2000 have not adaptive management experiment in British exceeded 150 t. Coast-wide, the fishery is Columbia as described in the Integrated dominated by south coast landings (Perry Fishery Management Plan. Adaptive and Waddell 1999). All of Masset Inlet management is discussed below. The Haida (PFMA 1-6) is closed to commercial fishing Gwaii closure is part of such an experiment, as an allocation to Haida food fishing now halfway through its 10-year life. It is (Figure 29). possible that the fishery could be reopened for Haida Gwaii at some time after this experiment. 112 SHELLFISHERIES MANAGEMENT • each fishery is unique in the blend of SUMMARY biological and management criteria used; Shellfisheries management is a moving • DFO attempts to provide a scientific target involving multiple species with basis for all management advice; and criteria changing according to fluctuating • not all fisheries depend on stock stock status and new technical information. assessments for their management. Nonetheless, an overview of the basics is provided here. The major shellfisheries The species’ life histories and the human occur mostly inshore with the exception of understanding thereof dictate the Dungeness crab in the northwestern region management criteria and will influence of Hecate Strait (Table 24). Among those future spatial management decisions. For with offshore landings (Dungeness crab and Gwaii Haanas, management of the most red sea urchin), almost 100% of landings are important fisheries is based on total in the east and northern offshore (PFMAs allowable catches arising from stock 101 and 102) compared to the west and assessment (geoduck and red sea urchin) southern offshore (PFMAs 130 and 142). and the prawn spawner index. There is a high local (HFP) labour input into stock With so much shellfisheries information, a assessments for the diving fisheries. quick management overview is warranted. Summarized in Table 25 are the Other issues relevant to fishing warrant management criteria for the major mention as follows: shellfisheries of Haida Gwaii. The main points are as follows: • Land-based pollution - the low population levels of Haida Gwaii region with attendant low levels of land-based 113 pollution render habitat degradation • Sea-based pollution – this is a genuine and pollution minor issues compared to threat, such as oil pollution from a some urban and industrial mill- shipping incident offshore or from an oil associated south coast areas of British or gas production platform blowout Columbia (Orensanz and Jamieson should development of the known 1998). For example, there has been no reserves of Hecate Strait occur. Spilled logging in the Gwaii Haanas area since oil can have significant short-term acute 1987, no other industrial upland activity affects, long-term chronic effects and oil for decades and there will always be can persist for decades in sheltered very little built infrastructure in the area. marine shore habitats (Sloan 1999). Elsewhere in Haida Gwaii, logging is Recoverable resources are estimated at active and there are downstream effects »414 million m3 [2.6 billion barrels] of oil such as increased sedimentation in and »565 billion m3 [20 trillion ft3] of gas nearshore waters. Coal and mineral in Hecate Strait (Dietrich 1995). There exploitation were important post- have been federal and provincial contact exploration and settler moratoria on exploration in waters attractants (Richardson 1873; Morton around Haida Gwaii since 1972. In 1992).

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