Rapid recovery of Dungeness crab within spatial fishery closures declared under indigenous law in British Columbia

Canada’s constitution grants indigenous people priority access to marine resources, yet indigenous, commercial and recreational fishers target the same species. Avoiding conflict between different users, therefore, requires evidence-based policies that manage fisheries for conservation while respecting indigenous rights. From 2006 to 2015, Canada’s Conservative government demoted the role of science in resource management, stifling research by federal agencies like Fisheries and Oceans Canada. To address ensuing data gaps, during 2014–2015 the Heiltsuk, Kitasoo/Xai’Xais, Nuxalk, and Wuikinuxv First Nations conducted coordinated research on Dungeness crab (Cancer magister), a culturally-significant resource. These indigenous groups are experiencing declining catch rates of Dungeness crab and postulate that commercial and recreational fisheries are primary causes of local declines. Accordingly, they applied indigenous laws and declared spatial fishery closures for commercial and recreational fishers at 10 sites (closed) while allowing exploitation by all users to continue at 10 other sites (open). Sampling occurred repeatedly over time and analyses compared temporal trends in population characteristics between closed and open sites. Results were consistent with the hypothesis that fisheries decrease the abundance and size of exploited species, but spatial protection can reverse these effects. The body size and catch-per-unit effort of legal-sized males increased over time at closed sites but declined at open sites. Importantly, fishery status did not affect temporal changes in the relative abundance of unfished classes of crab–sublegal males and females–which is logically consistent with the hypothesis. Our study demonstrates that indigenous governance can create spatial closures for conservation and research when Canada’s government fails to do so. Long-term solutions, however, require collaboration in research and management between federal and indigenous governments. Towards that end, Canada’s newly elected Liberal government has begun to restore federal science and to address indigenous rights, thereby enhancing the possibility of such collaboration.