Has krill fishing the potential to adversely affect recruitment in Antarctic notothenioid fishes?

A few years after krill (Euphausia superba) fishing had started in 1972/73, it became known that early life stages of Antarctic fish are associated with krill aggregations and are subject to by-catch in fisheries targeting krill. The species composition of fish by-catch in krill fisheries is well-known from Polish investigations in the late 1970s and the 1980s and from Japanese, Ukrainian, and Russian investigations in the 1990s, 2000s and 2010s. However, only a few investigations in the 1990s and 2000s made attempts to estimate the quantity of by-caught fish. They demonstrated that, on occasions, the by-catch was substantial. Fish by-catch in krill fisheries has been discussed in WG-FSA since the mid-1980s. However, the problem has been largely neglected subsequently to the extent that more than 25 years later WG-FSA is still not in the position to estimate the amount of fish by-catch reliably and to decide on the significance of the problem. Modelling approaches conducted recently in Norway to resolve the problem are encouraging. To make further progress, a broad outline of a programme is presented for further discussion in WG-FSA in October 2014.