How Should We Harvest an Animal that Can Live for Centuries?

Abstract

AbstractThe ocean quahog Arctica islandica is an extremely long‐lived and slow‐growing marine bivalve that supports fisheries in several countries bordering the northern Atlantic ocean. The life history of the ocean quahog presents several unique challenges to fishery managers. Scientists currently have a poor understanding of recruitment and how it might respond to declining population biomass due to fishing pressure, in part because most fisheries have operated for less than one ocean quahog generation. It is therefore difficult to develop management quantities, such as biological reference points, by using traditional means. This simulation study examines ocean quahog recruitment dynamics and explores the implications of a suite of fishing intensities and biomass reference points. Results support the following recommendations: (1) ocean quahog fisheries should be prosecuted with very low fishing mortality rates (F), as Ftarget values greater than 0.03 tended to result in fishery closures while not having much effect on yield; (2) given a low Ftarget, ocean quahog fisheries are likely to tolerate a relatively low biomass threshold value; and (3) an understanding of spatial structure is important for maintaining a functional ocean quahog fishery.Received July 28, 2015; accepted January 26, 2015