Temporal and Spatial Patterns of Pacific Cod Spawning in the Bering Sea

Pacific cod are an important commercial and ecological species in the Bering Sea though, with semi-demersal eggs that elude plankton survey nets, little is known about the distribution of eggs and early larval stages.  Lacking this information poses a challenge for fishery managers in determining estimates of recruitment.  Between 2003 and 2005 members of the Fisheries Interaction Team with the Alaska Fisheries Science Center worked to develop a visual maturity key for Pacific cod.  The key had been deployed with Fisheries Monitoring and Analysis Division groundfish observers working on commercial vessels in the Bering Sea since 2004. Observer collected maturity data, along with ovary histology are being analyzed to 1)evaluate the subjectivity of the maturity key, 2) identify patterns of Pacific cod spawning behavior, and 3) and map Pacific cod spawning locations.  These maps will help fill data gaps and provide information important to fisheries managers.