How Uncertainty in Natural Mortality and Steepness May Affect Perception of Stock Status and Fishery Sustainability in Atlantic Surfclam: A Simulation Analysis

The Atlantic surfclam (Spisula solidissima) is an important commercial fishery resource on the U.S. MidAtlantic continental shelf. Although 2016 stock assessment found that surfclams are neither overfished nor overfishing occurring, uncertainty in scale of spawning biomass persists. As a consequence this uncertainty, Fishery Management Council (MAFMC) lowered acceptable biological catch 2016. A simulation analysis was developed for to estimate risk associated with recommendation and its adherence MAFMC policy. Operating models conditioned model structure generated simulations population, alternative represent steepness (h) stock-recruitment curve natural mortality (M). Simulations were forecasted under variety management procedures evaluated estimation spanned h M. Results showed current decisions more conservative than stated risk-tolerance policies, though overestimating could lead misrepresentation as within thresholds. Further future economic viability by estimating proportion fishable clam patches given historical observations density. able support sustainability generally stable despite uncertainties, declined increasing fishing pressure. This work contributes efforts evaluate environmentally economically sustainable strategies.