Crustacean resources are vulnerable to serial depletion - the multifaceted decline of crab and shrimp fisheries in the Greater Gulf of Alaska

The seas around Alaska support (or have supported) some of the most commercially significant crustacean stocks in the world, spread over an overwhelming array of extensive and diverse coastal and open shelf areas. Major resources include three species of king crab (Paralithodes spp. and Lithodes aequispina), Tanner and snow crab (Chionoecetes spp.), Dungeness crab (Cancer magister), and five species of pandalid shrimp (Pandalus spp. and Pandalopsis dispar). Excluding the Bering Sea, the resources from the Greater Gulf of Alaska (ranging from the Aleutian Chain to the state's southeastern panhandle contiguous with British Columbia) supported rapid expansion of several crab and shrimp fisheries during the 20 year period 1960-1980. Since then, most of those fisheries have collapsed. While some of the stock declines have been well documented and discussed (most prominently the `dethroning' of red king crab on the shelf around Kodiak Island), it has been less apparent that the demise of Alaskan crustacean stocks is a process on a much larger scale, and is still unfolding. Here we examine trends in catch, recruitment and abundance (when possible) and discuss existing evidence of overfishing and management options. We emphasize the importance of recognizing the multi-scale spatial structure of crustacean stocks, and suggest the need to consider spatially explicit strategies, particularly the creation of reproductive refugia.