Low anthropogenic mortality of humpback ( <i>Megaptera novaeangliae</i> ) and killer ( <i>Orcinus orca</i> ) whales in Norwegian purse seine fisheries despite frequent entrapments

Fishery inspector logbooks were used to estimate fishing gear interaction rates for humpback (Megaptera novaeangliae) and killer (Orcinus orca) whales in Norwegian purse seine fisheries herring from 2011 2020. Estimated applied data fleet-wide totals. Estimates showed that a 10-year period, total of 78 whales, 95% CI [41, 145] 100 [63, 176] entrapped seines. Most disentangled alive, with an estimated mortality 5%, CV 0.69, [0.0, 11.8] 6%, 0.48, [0.3, 11.9], respectively. The average yearly over the study period was thus approximately 0.60 0.39 corresponding 0.008% 0.007% respective abundance estimates these whale species waters. Given Potential Biological Removal sustainability limits 98 humpbacks 161 per year, it may be concluded that, by itself, incurred populations does not constitute significant risk either species, but bycatch only source anthropogenic mortality.