ABSTRACT
Populations of red king crab (RKC) Paralithodes camtschaticus (Tilesius, 1815) and blue king crab (BKC) P. platypus in Alaska have uctuated greatly over the last three decades (Chilton et al., 2011). After peak landings in 1980, the RKC sheries in the Bering Sea and Kodiak, Alaska, were closed in 1983. Although the Bering Sea shery reopened in 1984, the shery in Kodiak, Alaska, has never been reopened due to low population abundance. Other commercial sheries in the Bering Sea, including snow crab (Chionoecetes opilio) and Tanner crab (C. bairdi) are considered to be over-shed, and the latter has been closed since 1996. At the Pribilof Islands, BKC shery was closed from 1988 to 1994 and reopened in 1995; both sheries were closed in 1998 (NPFMC, 2002). The shery at St. Matthew Island reopened in 2010, but the Pribilof Islands shery remained closed. Simultaneously, the population of RKC in the Pribilof Islands has increased since 1991, but no directed shing for RKC has occurred there since 1998 in order to prevent the bycatch of BKC. Although there is great uncertainty about the ultimate cause of recruitment variability (Blau, 1986), many hypotheses have been proposed, including egg predation (Kuris et al., 1991), disease, overshing (Orensanz et al., 1998), bycatch (Dew and McConnaughey, 2005), and climatic changes (Zheng and Kruse, 2000). Changes in spatial distribution associated with climate variability may also be involved (Loher and Armstrong, 2005), but the linkage between environmental change and population abundance is not yet understood.
