Inter-Research > MEPS > v403 > p219-230  
Marine Ecology Progress Series

via Mailchimp

MEPS 403:219-230 (2010)  -  DOI:

Biomass and mortality of chum salmon in the pelagic Bering Sea

Masa-aki Fukuwaka1,*, Shunpei Sato2, Orio Yamamura1, Osamu Sakai3,4, Toru Nagasawa1,2, Akira Nishimura1, Tomonori Azumaya1

1Hokkaido National Fisheries Research Institute, Fisheries Research Agency (FRA), 116 Katsurakoi, Kushiro 085-0802, Japan
2National Salmon Resources Center, FRA, 2-2 Nakanoshima, Toyohira-ku, Sapporo 062-0922, Japan
3Graduate School of Fisheries Science, Hokkaido University, 3-1-1 Minato-cho, Hakodate 041-8611, Japan
4Present address: National Research Institute of Far Seas Fisheries, FRA, 5-7-1 Orido, Shimizu-ku, Shizuoka 424-8633, Japan

ABSTRACT: To provide a key piece of information for understanding the functioning of the Bering Sea pelagic ecosystem, we estimated the biomass of immature chum salmon in the Bering Sea basin in autumn using a return-at-age analysis incorporated with the results of genetic stock identification studies. The estimated biomass was 742000 t in 2002 and 617000 t in 2003, which is possibly an underestimate because of the uncertainty of trawl selectivity parameters used in the estimation. Although chum salmon has been the dominant nekton species in the pelagic ecosystem of the Bering Sea basin in recent years, biomass estimates for the species were smaller than one-tenth of the maximum biomass of walleye pollock in the 1980s. Previous studies have highlighted the importance of the huge biomass of mesopelagic planktivores, such as myctophid fishes and gonatid squid, to the ecosystem function of the pelagic Bering Sea. Planktivorous Pacific salmon including chum and pink salmon may also play a significant role as competitors and predators of small planktivores, thus affecting the dynamics of ecosystem function and nekton community structure in the pelagic Bering Sea.

KEY WORDS: Pelagic ecosystem · Planktivores · Biomass estimate · Salmon · Catch-at-age analysis · Genetic stock identification · Markov chain Monte Carlo

Full text in pdf format 
Cite this article as: Fukuwaka M, Sato S, Yamamura O, Sakai O, Nagasawa T, Nishimura A, Azumaya T (2010) Biomass and mortality of chum salmon in the pelagic Bering Sea. Mar Ecol Prog Ser 403:219-230.

Export citation
Mail this link - Contents Mailing Lists - RSS
Facebook - - linkedIn