What Is the Real Fishing Mortality? Revealing the Hidden Post-Release Mortality of Atlantic Cod in Marine Recreational Fisheries

Atlantic cod is one of the most popular target species in many marine recreational fisheries. Surveys have shown that recreational anglers account for a significant portion of the total cod harvest in several countries which needs to be considered in future stock assessments. In addition, a large proportion of the catch is released due to voluntary and regulatory catch-and-release practices. To obtain accurate estimates of fishing induced mortality, one has to account for post-release mortalities which may occur as a consequence of catch-and-release. In recent years, several post-release studies on Atlantic cod have been conducted covering a range of potential mortality factors including anatomical hooking location, water temperature, air exposure and capture depth. Bleeding and high water temperatures significantly increased post-release mortality of cod, while fish without substantial hooking injuries were found to have high survival potential. Using information on recreational fishing practices in different marine recreational fisheries, e.g. commonly used lure types and capture depths, we present a range of post-release mortalities estimates for those fisheries. The findings of this paper will lead to more accurate fishing mortality estimates, and have important implications for fisheries management, e.g. potential exemption of recreational cod fisheries from the EU discard ban.