Fishers and whales in Iceland

Abstract

In Iceland, as in many places globally, the detrimental impacts of whale interactions with fishing gear on both fisheries and whales are not well understood and managed. This study conducted anonymous questionnaires of Icelandic fishers and interviews of capelin purse seine boat captains to gather first-hand knowledge of the issues fishers face due to whale interaction with their fishing gear. Results suggest that the humpback whale is the large whale species that is most often entangled or encircled in fishing gear and causing damage, however on occasion other large whale species are interacting with gear as well. Interactions between humpback whales and fishing gear appears to be primarily concentrated in the north/northeast and southwest of the country where there is high fishing effort and known humpback whale feeding habitat. Humpback whale interactions with gear occurred most often with capelin purse seines, which are targeting humpback whale prey, and data suggests that bycatch of whales in this fishery may be underreported. Damage and losses due to whale collisions with gear were reported to cost fishers up to 55.000.000ISK, suggesting this can be a costly issue for which mitigation measures should be explored. The use of acoustic “pingers” is one mitigation measure that has been previously tested by capelin purse-seiners and is something that captains indicated they would be interested in continuing to try. The creation of a whale entanglement/whale-gear interaction reporting system in Iceland would aid in gathering more data and quantifying how often these events are witnessed and what the consequences of these events are to both the fishers and the whales. This study provides new information about the consequences of large whale interactions with Icelandic fisheries and suggests that future collaboration with fishers can provide insight contributing to best management practices for sustainable fishing and whale conservation.

Non‐lunge feeding behaviour of humpback whales associated with fishing boats in Norway

“…This foraging strategy might be associated with low energy costs because it reduces the need for animals to search and chase prey items. Despite interactions with fishing boats being well studied in many species (Bonizzoni et al., 2022; Read, 2008), only recently have incidents of baleen whales interacting with fishing boats been reported (Basran & Rasmussen, 2021), and it is unknown whether they utilise discard fish as a food source. Rorqual whales are known to forage by lunge feeding, an energetically expensive foraging strategy where an individual rapidly accelerates before engulfing a large volume of prey‐laden water (Goldbogen et al., 2017).…”

“…In the coastal area of Tromsø, north Norway, local fishermen operate set net fishing for herring Clupea harengus which attracts killer whales Orcinus orca around fishing boats for opportunistic feeding events (Mul et al., 2020). Humpback whales Megaptera novaeangliae , a rorqual baleen whale species, also feed on herring in this region (Jourdain and Vongraven 2017) and have recently been reported to conduct similar interactions with these fishing boats (Basran & Rasmussen, 2021). Discard fish are a potential low‐cost food source for humpback whales.…”