Biological reference points for spiny dogfish

"Biological reference points are a critical component for the stewardship of fishery resources. Appropriate target levels of biomass and harvest rates allow managers to set regulations consistent with maximum sustainable yield, or an appropriate proxy. The primary focus of this report is to revise the biomass reference points for spiny dogfish (Squalus acanthias), and to update the fishing mortality reference points using the most recent catch and survey information. Previous biomass reference points for spiny dogfish were based on a Ricker stock-recruitment model derived from Northeast Fishery Science Center trawl survey data. SSBmax, the biomass that results in the maximum projected recruitment, is the proxy for BMSY. The revised biomass reference point incorporates additional information on the average size of the recruits as an important explanatory variable. A hierarchical AIC-based model building approach is used to identify the best model. Comparisons of maximum likelihood and robust nonlinear least squares regression models suggested that the robust estimator had the lowest AIC and highest precision for the estimate of SSBmax"--Executive summary. by P.J. Rago and K.A. Sosebee. "May 2010." Includes bibliographical references (pages 14-15).