The effect of abundance changes on a management strategy evaluation for the Atlantic surfclam (Spisula solidissima) using a spatially explicit, vessel-based fisheries model

Increased bottom water temperatures have caused a relocation and contraction of the range of the Atlantic surfclam, Spisula solidissima, in the Mid-Atlantic Bight (MAB). Consequences include declining stock abundance and landings per unit effort (LPUE) in southern portions of the range. A management strategy evaluation (MSE) assessed the potential of rotational closures to improve surfclam productivity and fishery viability under three levels of abundance. In simulations, fishing vessels harvest the stock under performance and quota constraints and captain behavioral proclivities. Management alternatives examined included the addition of area manage. ment to the current management plan using two closure location rules and three closure durations at two levels of incidental mortality. Simulations showed that area management increased stock abundance and fishery LPUE, particularly when surfclam abundance was low. Simulations suggest area management could help insulate the stock and commercial fishery from further shifts in range.