ORIGINAL ARTICLE Seals and fyke nets: An investigation of the problem and its possible solution SARA KO ¨ NIGSON, MALIN HEMMINGSSON, SVEN-GUNNAR LUNNERYD & KARL LUNDSTRO ¨ M Swedish Board of Fisheries, Box 423, 401 26 Go ¨ teborg, Sweden Abstract During the last few decades, the economically important eel (Anguilla anguilla ) fishery with fyke nets along the Swedish west coast has been subjected to damage caused by harbour seals (Phoca vitulina ). To protect fyke nets from seals, the netting in the fish bags was replaced with stronger material. The level of damage decreased when fishing with modified fyke nets, compared with when traditional fyke nets were used. The stronger fyke nets were, however, still exposed to a notable level of attack from seals, even if the resulting damage was minor compared with that suffered by the standard fyke nets. There was no difference in the catch per unit effort when comparing the most effective modified fyke nets with the standard fyke nets. By testing exclusively modified fyke nets in certain areas, and only standard fyke nets in other fishing areas some distance away, the levels of damage were reduced in the areas with only modified fyke nets. By replacing traditional fyke nets with modified fyke nets, fishermen can make it less profitable for seals to use fyke nets as food stores, with less gear damage and zero catch losses as a result. Using modified fyke nets in the commercial eel fishery is both practical and rewarding for the fishermen. Key words: Conflict, eel fishery, fisheries interaction, fyke net, harbour seals, Phoca vitulina, modified fyke nets, Sweden Introduction Seals along the Swedish coast interact with fisheries in many ways. The negative impacts include direct interference with fishing gear and catches, competi- tion for the resource, entanglement in fishing gear and the dispersal of parasites (the latter leading to a reduction in the value of commercial fish) (Gulland 1987). In this region, it is the eel fishery that suffers the greatest losses due to seals (Ko ¨nigson et al. 2003) and it is the damage to fishing gear and catches that concerns us here. The west coast eel fishery is economically one of the most important segments of the Swedish small-scale fishing industry. Fyke nets, pound nets and traps are the types of fishing gear commonly used, with fyke nets being the principal gear in use. Fleets of up to 10 fyke nets are placed in shallow waters in coastal areas. Fyke nets most often consist of two fish bags and a leading net in between (Figure 1). Fish follow the leading net into the fish bag, where they are trapped. The catch in fyke nets is mixed, containing partly eels (Anguilla anguilla ), but also several by-catch species, including cod (Gadus morhua ) and flounder (Platichthys flesus ). Damage to the fyke nets is mainly caused by the harbour seal (Phoca vitulina ), which is the dominant seal species on the west coast. Grey seals (Hali- choerus grypus ) also occur in this region, but only in very small numbers (Ha ¨rko ¨nen & Lunneryd 1990). Cormorants (Phalacrocorax carbo ) are believed to cause similar damage to fyke nets, but harbour seals are responsible for most of the trouble (Ko ¨ nigson et al. 2003). The frequency of incidents of damage is reported by fishermen to be highest in the early spring and late autumn. Fishermen have also stated that levels of damage increase after stormy weather. Damage consists of tears or small holes in the net, mainly in the fish bag where the fish gather. Eels are also dragged through the mesh itself and bitten in half. This results in the fishermen losing the whole catch from the damaged fish bags and also having to repair their fishing gear, which is time-consuming. Correspondence: Sara Ko ¨nigson, Fiskeriverket, Box 423, 401 26 Go ¨teborg, Sweden. E-mail: Sara.konigson@fiskeriverket.se Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark Marine Biology Research, 2007; 3: 29  36 (Accepted 18 October 2006; Printed 5 March 2007) ISSN 1745-1000 print/ISSN 1745-1019 online # 2007 Taylor & Francis DOI: 10.1080/17451000601072596