Estimating Total Post‐Release Mortality in a Boat‐Based Recreational Fishery

Catch‐and‐release angling is widespread in marine recreational fisheries resulting from the implementation of enforced minimum legal sizes and increasing uptake of voluntary release. This makes recreational fisheries selective, with high release rates in certain cases. We estimated the post‐release mortality of the boat‐based recreational snapper fishery in northeastern New Zealand by characterising catch‐and‐release practices on private and charter boats, collecting data on fish length, depth of capture, anatomical hooking location and whether the fish was kept or released. Combining this data with harvest estimates from national diary surveys, a length‐weight regression and published mortality probabilities based on depth and hooking location, we estimated annual release mortality at 200 t (95% CI [194, 216]) for private boats and 48 t (95% CI [43, 51]) for charter boats. Despite this level of post‐release mortality representing 22% of recreational snapper releases, a recent assessment showed the stock to be in a favourable state.