States, municipalities, and small scale artisanal fisheries that manage on a local scale might benefit from the recent development of methods to evaluate data-poor fisheries. Two catch-based methods, Depletion-Correct Average Catch (DCAC) and Depletion-Based Stock Reduction Analysis (DB-SRA), are currently in use at the coast-wide scale. Our goal was to apply both methods at diminishing spatial scales, from coast-wide to Oregon state territorial sea, and at a regional scale within Oregon. Leaving management and allocation issues aside, we found that the harvest limit estimates from DCAC and DB-SRA are sensitive to diminishing spatial scales such that the harvest limit estimates are increasingly influenced by the catch time-series. Differences in the catch-time series across regions can be caused by a number of scenarios, both biological and non-biological including less habitat, less fishing effort, market for the fish, and processor location. Since these methods are not designed to determine the cause for the differences in catch, we suggest that the harvest limit estimates must be interpreted through the lens of specific “components” that influence both the population dynamics and the fishery on a local or regional scale. We propose a framework to interpret harvest limit estimates that specifically addresses regional and local dynamics.
Selina S. Heppell, Department of Fisheries and Wildlife, Oregon State University
Linsey Arnold, Department of Fisheries and Wildlife, Oregon State University
Sea Grant #NA10OAR4170059