Spawning Dynamics and Associated Management Implications for Atlantic Cod

Abstract

Many stocks of Atlantic Cod Gadus morhua have been depleted due to interactions between overfishing and environmental variation. Stock declines were often accompanied by reductions in spawning diversity and collapses of population structure. Studying Atlantic Cod spawning activity can provide insights into the mechanisms involved in rebuilding. This paper reviews the existing literature on Atlantic Cod spawning dynamics, including habitat, timing, behavior, gamete production, larval survivorship, and fishery impacts. The associated implications for fisheries management are discussed, and critical information gaps are identified for inclusion in future research. Of primary importance for consideration by fisheries managers are the spatial and temporal extent of spawning, the behavior of spawners, and the reproductive contributions of older age-classes. The application of spawning closures as part of a multidisciplinary approach to fisheries management is advocated to prevent the disruption of spawning activity and the extirpation of semidiscrete spawning components. Integrating information on Atlantic Cod spawning dynamics into fisheries management plans will better account for reproductive processes, which is expected to promote rebuilding and decrease the risk of further collapses of population structure.

Received August 22, 2013; accepted December 17, 2013

ACKNOWLEDGMENTS

We acknowledge Michael P. Armstrong, Geoff Cowles, William Hoffman, and Lisa Kerr for their input and suggestions with respect to topics discussed in this review. We also thank Fiona Hogan and David Martins for their edits on an early draft of this paper. Thanks to Michael Palmer and an anonymous reviewer whose comments improved the quality of this paper. This work was completed by the primary author in partial fulfillment of a Ph.D. in Marine Science at the University of Massachusetts–Dartmouth through the School for Marine Science and Technology. Funding for this work has been provided in part by the United States Fish and Wildlife Service through the Sportfish Restoration Act and the Massachusetts Marine Fisheries Institute.