Information by Fishery
Commercial Sea Urchin Dive Fisheries
Two sea urchins species are commercially harvested in Alaska. The red sea urchin (Mesocentrotus franciscanus) is the larger, longer-spined species and is the target in the state’s largest urchin fishery in Southeast Alaska (sea urchin management activities). The green sea urchin (S. droebachiensis) is a smaller species with shorter spines taken in a small commercial fishery principally in the Kodiak area. Red sea urchins occur from Baja California north to the Gulf of Alaska and sparingly to Kodiak, whereas the green sea urchin is circumpolar in the northern hemisphere, occurring in the eastern Pacific from Washington State to the Arctic Ocean. Red sea urchins occur primarily on rocky shorelines of the outside coast with highest densities in the subtidal range down to 40 feet. Green sea urchins are found in a wider variety of habitats, and especially in more protected waters and embayments. Highest concentrations occur from the intertidal to depths of 30 feet. Both species feed on kelps and other algae.
The urchin fishery on the west coast of North America began in Southern California where urchins were originally considered pests. Prior to the realization that urchin roe was a valuable commodity, kelp harvesters would spread lime to kill urchins, and divers would manually crush urchins to promote kelp bed growth. As the Japanese market developed for California urchins in the 1970s, fisheries expanded north to include Oregon, Washington, and British Columbia.
Harvests of urchins in Alaska began in 1980 in the Kodiak area where a small green sea urchin fishery began and continues at a minimal level to this day (harvests, 1980-2002). Harvests in Southeast Alaska began in 1981 near Ketchikan, for both red and green sea urchins, with the vast majority of the harvest comprised of red urchins. This fishery closed in 1989 in the Ketchikan area due to marketing difficulties. A subsequent small scale harvest of red sea urchins in the Sitka area from 1991 to 1993 succumbed to marketing difficulties and extreme predation by sea otters.
The Southeast Alaska fishery was jump-started in 1995–1996 when a large, 3 million lb test fishery for red sea urchins was conducted in the Ketchikan area to evaluate the economic feasibility of the fishery and to provide funds for stock assessments. A management plan was adopted by the Board of Fisheries in 1997 establishing a conservative harvest rate approach, and requiring stock assessment surveys prior to harvests. The Commercial Fisheries Entry Commission limited entry of harvesters into the fishery in 2000.
In response to interests in developing a green sea urchin fishery in Southeast Alaska, the department, in consultation with the Southeast Alaska Regional Dive Fishery Association (SARDFA) developed an exploratory stock assessment program funded largely with Federal monies beginning in 1999. The program included reconnaissance surveys by commercial dive harvesters and subsequent biomass surveys conducted by the department. The conclusion from these assessments was that the green urchin resource was inadequate to support a commercial dive fishery, primarily because population densities were too low and urchin sizes were too small.
Red sea urchin management in the panhandle is guided by the Southeastern Alaska Red Sea Urchin Fishery Management Plan (5 AAC 38.145), which specifies a conservative harvest rate of no more than 6% of the biomass of large (> 60mm shell diameter) red sea urchins. Biomass estimates are made once every three years in 20 or more harvest areas coinciding with salmon statistical areas that average roughly 75 km in length. Several control areas where no harvests occur are also monitored for environmental effects on urchin populations that are independent of urchin harvesting. The department works in close cooperation with SARDFA in developing proposals for new or revised regulations to present to the Board of Fisheries for consideration.
The green sea urchin fishery in Kodiak and areas westward is managed under the authority of a Commissioner’s permit for miscellaneous species (5 AAC 38.062) that specifies harvest locations, season length, and guideline harvest levels. Boundary lines established for Tanner crab and sea cucumbers are used for green urchin management in the Kodiak area, with maximum GHLs of 10,000 and 5,000 lb depending on historical production.
Urchin harvests are limited to hand picking and use of an urchin rake. Divers typically use surface supplied air or scuba gear and collect urchins in mesh bags that are lifted to the surface.
Recent Harvest and Status
Statewide urchin harvests have been tailing off due to lower market demand for uni. Average harvests in the 5-year period ending in 2004 were 2.8 million lb at an average price of about 33 cents per lb. (5-yr avg harvest, 2000-2004).
Conservation and Other Issues
The major emphasis of the management program for red sea urchins in Southeast Alaska has been to avoid over harvest as has occurred in urchin fisheries elsewhere; however, the impact of expanding sea otter populations may be of much greater magnitude. Fishery development efforts in the Sitka area in the early 1990s were thwarted when the local sea otter population underwent a significant expansion south of town, decimating urchin stocks. Sea otter populations are just a few miles outside the boundaries of existing stocks of red sea urchins in southern Southeast Alaska that now support much of the fishery.
[Based on excerpts from the publication, Commercial Fisheries in Alaska, Woodby et al. Alaska Department of Fish and Game, Special Publication 05-09, June 2005 (PDF - 1,059K). Information or data on this web page may have been updated and may no longer match the original publication.]