Feasibility and effectiveness of seal deterrent in coastal trap-net fishing – development of a novel mobile deterrent

With the rapid growth of grey seal (Halichoerus grypus) population in Baltic Sea, seal-induced catch losses have increased dramatically coastal fisheries. There been various attempts to mitigate these damages, such as modification fishing gear, but solutions proven inadequate. Promising research results recently obtained by using acoustic deterrent devices (ADDs) keep seals away from immediate vicinity gear. We tested feasibility and effectiveness a raft-mounted novel mobile ADD salmon (Salmo salar) trap-net fisheries along Finnish coast collaboration with 13 commercial fishers. Fishers operated trap-nets (pontoon traps) that were equipped without an ADD. Our indicate fisher can expect on average 3.4 per day whereas 2.1 day. The deployment ADDs over two years testing period indicated increase 64% catches. study suggests is useful economically viable (given investment subsided) mitigation tool for reducing losses. Furthermore, developed this provides unique practical opportunities notable potential wider use