Release and recovery locations for 2009 tags. (Larger image)

Ongoing Research
The Auke Bay Laboratories is involved in a number of shark research projects, many in cooperation with academic institutions. Projects with Pacific sleeper shark are focused on determining population size, migration patterns, and their trophic level (with the University of Alaska Fairbanks). Scientists at ABL and the AFSC Age and Growth lab are investigating novel methods of aging both spiny dogfish and Pacific sleeper sharks, and also monitoring the reproductive development and growth of captive spiny dogfish. A multi-year tagging study of spiny dogfish is underway in cooperation with the University of New England. Data for these tags are transmitted by satellites and give us information on the depths and locations that spiny dogfish inhabit throughout the year. This study began in 2009 and the final tag deployment will occur in 2011. Links to the cruise reports for the tagging study are below:

2009 shark tagging survey cruise report
2010 shark tagging survey cruise report

Tagged Shark Recovery Poster

Shark species in Alaska
There are three species of sharks that are abundant in Alaska waters: Pacific sleeper shark, Somniosus pacificus, spiny dogfish, Squalus suckleyi , and salmon shark, Lamna ditropis. Currently there is no directed fishing for these species, but they are caught incidentally in other fisheries. Little is known about these sharks’ life histories in Alaska, but research on their ages, natural mortality, movements, diets, and maturity is ongoing.

Pacific sleeper sharks caught on a research vessel in the Gulf of Alaska.

Pacific Sleeper Sharks
Pacific sleeper sharks are the largest of the shark species encountered in the Gulf of Alaska and Bering Sea, growing up to 7 meters. This species ranges as far north as the Arctic Circle in the Chukchi Sea, west off the Asian coast and the western Bering Sea, and south to California. Pacific sleeper sharks are the most abundantly caught shark in the Bering Sea surveys, yet catches are unreliable and do not provide good estimates of biomass. The species feeds mostly on fish, cephalopods, and sometimes marine mammals, and although they were once thought to be bottom dwelling, it is now known that they use much of the water column. This species has proven very difficult to age and due to the large size they are difficult to sample. Thus, little is known about their growth, longevity, the age at which they become mature, and the length of gestation.

Two spiny dogfish caught on sport fishing gear.

Tagged spiny dogfish ready for release.

Spiny Dogfish
Spiny dogfish in the North Pacific Ocean are a distinct species (S. suckleyi), but were until recently considered the same species as those spiny dogfish (S. acanthias) found on the U.S. east coast and other oceans of the world. Subsequently, much of the research refers to S. suckleyi as S. acanthias. Spiny dogfish range from the Bering Sea to the Baja Peninsula with the center of abundance believed to be in the waters around Washington State and British Columbia (Canada). In the Gulf of Alaska, spiny dogfish are the most prominent shark species in the NMFS biennial trawl surveys and annual longline survey. This species has been heavily fished in both British Columbia and Washington State, but they have only ever been a bycatch species in the Gulf of Alaska.

Spiny dogfish are the most well studied of the three main shark species in the Gulf of Alaska. Numerous studies have been published or are ongoing regarding this species. Spiny dogfish are longest lived and slowest growing of all shark species studied, living to 100 years or more and females do not reach maturity until they are 36 years old. Reproduction is also slow for this species, gestation takes nearly 2 years and females have about 9 pups on average. Diet studies shown that spiny dogfish do not target specific prey. Instead, they are opportunistic, feeding on whatever is available. Tagging studies are showing that spiny dogfish can undertake large scale migrations, moving from Canadian waters to Japan or Mexico, and they may inhabit areas previously unknown, such as pelagic waters far from shore.

Salmon shark caught on a research cruise in southeast Alaska.

Salmon Sharks
Salmon sharks range from Japan through the Bering Sea and Gulf of Alaska and south to Baja, Mexico. Salmon sharks are rarely encountered in commercial fisheries or trawl surveys in federal waters, but are more commonly caught in salmon fisheries and research surveys conducted by the Alaska Department of Fish and Game in nearshore waters. The species is also targeted by sport fishermen in Alaska, but catches are low. Tagging studies show that some animals may migrate thousands of kilometers south while others may over winter in Alaskan waters. Salmon shark tend to congregate during the summer in areas with dense salmon runs, especially Prince William Sound, Alaska, but they also feed on squid, sablefish, rockfish, eulachon, spiny dogfish, arrowtooth flounder, and Pacific cod.

Contact:
Cindy Tribuzio
Auke Bay Laboratories
Alaska Fisheries Science Center, NOAA Fisheries

Ted Stevens Marine Research Institute
17109 Pt Lena Loop Rd
Juneau AK 99801
(907) 789-6007
Cindy.Tribuzio@noaa.gov

Featured Research, Publications, Posters, Reports, and Activities

• CINDY TRIBUZIO, DAVID CLAUSEN, CARA RODGVELLER, JONATHAN HEIFETZ, and DORIS ALCORN. 2008. Research, Biology, and Management of Sharks and Grenadiers in Alaska. AFSC Quarterly Report Feature (April-May-June 2008) 9 p. (.pdf, 656KB).  Online.
   
• COURTNEY, D. L., and L. HULBERT. 2007. Shark research in the Gulf of Alaska with satellite, sonic, and archival tags, p. 26-27. In P. Sheridan, J. W. Ferguson, and S. L. Dowling (editors), Report of the National Marine Fisheries Service Workshop on Advancing Electronic Tag Technologies and Their Use in Stock Assessments. U.S. Dep. Commer., NOAA Tech. Memo. NMFS-F/SPO-82. 
   
• SIGLER, M. F., L. B. HULBERT, C. R. LUNSFORD, N. THOMPSON, K. BUREK, G. O’CORRY-CROWE, and A. C. HIRONS. 2006. Diet of Pacific sleeper shark, a potential Steller sea lion predator, in the northeast Pacific Ocean. J. Fish Biol. 69:392-405. 
   
• 2010 GOA Sharks SAFE report (.pdf).
• 2010 BSAI Sharks SAFE report (.pdf).

See the publications and poster databases for additional listings.