The potential role of marine reserves in the management of shortraker rockfish (Sebastes borealis) and rougheye rockfish (S-aleutianus) in the Gulf of Alaska

Shortraker and rougheye rockfish (Sebastes borealis and S. aleutianus) have been an independent management subgroup of the Gulf of Alaska slope rockfi sh assemblage since 1991. Special concerns are proposed for the management of these species because they are very slow growing, long-lived, and commer cially important. Marine reserves (harvest refugia) have often been proposed as a valuable ma nagement tool for mitigating overfishing and maintaining species and habita t diversity. Their effectiveness in fisheries management, however, is poorl y understood and concepts regarding their use are largely untested. Our stu dy investigated the potential role of harvest refugia in the management of these two species by using a Geographic Information System (GIS) applicatio n to design harvest refugia networks of varying spatial extent. Twenty-year projections employing a population dynamics model were used to compare end ing biomass and fishing mortality under the current management system with biomass and fishing mortality under refuge management systems. The results indicate that harvest refugia can be used to greatly reduce discards and se rial overfishing of substocks without reducing current catch levels.