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Obtaining sustainable fisheries in the Skagerrak Retrieval of lost fishing gear to reduce “Ghost fishing” Obtaining sustainable fisheries in the Skagerrak Retrieval of lost fishing gear to reduce “Ghost fishing” PUBLISHED BY Forum Skagerrak II WP3 Fish and shellfish LAYOUT Steve Hidinger YEAR 2007 Hemsida: www.forumskagerrak.com Introduction “Ghost fishing” is the term used for fishing gear that continues to catch marine organisms after they have been abandoned or lost at sea, are considered a potential source of significant unaccounted mortality (Chopin et al.,1995). Ghost fishing normally occurs with passive fishing gear such as longlines, gill nets, entangling nets, trammel nets, traps and pots. Facts Fishing gear can continue fishing long after they are lost or abandoned, e.g. gillnets are expected to continue fishing for up to seven years if lost in waters more than 400 meters depth. Large fish or cetaceans approach nets to feed on the smaller entrapped fish and can also get caught. In a struggle to free themselves they contribute more and more to the decreasing catching area of the net. Nets or bits of nets can be washed ashore by coastal or oceanic currents. During the floating stage seabirds might get trapped when diving for fish or parts of fish still trapped in the net. Traps and pots operate slightly differently from gill nets and entangling. They are almost always moored on the bottom with a line and float to mark their position. Fish and crustaceans are usually attracted to the trap or pot by means of bait. Once in the trap or pot, the fish or crustacean cannot escape. In the case of lost gear, the trapped fish do not die immediately but once the food supply runs out they may starve. However, the trapped fish may become the "bait" for other fish. It is this 'rebaiting' of the trap by captured fish or crustaceans that forms the basis of ghost fishing by this gear. Retrieval of lost fishing gear in the Skagerrak Since 1980 the Norwegian Directorate of Fisheries have organised retrieval surveys for lost fishing gear in Norwegian waters. Focus areas have been the deeper waters off the coast of mid- and northern Norway. Sweden have performed similar surveys in The Baltic Sea and Øresund (the waters between Sweden and Denmark) since 2001. No surveys have been conducted in the Skagerrak, but increased focus on the issue from both EU and Norway, may change this situation. When establishing Marine Protected Areas (MPAs), all lost fishing gear and rubbish that may trap fish or other marine life should be removed. In limited areas searching and localising fishing gear and rubbish can effectively be performed by divers and underwater cameras. The findings can then be retrieved by a relatively simple gear e.g. drag and hook. The retrieval method used by Norwegian Authorities is relatively large scale and hence best suited for deeper waters. It is mostly used to remove gilnets, a fishing gear that is not much used in the Skagerrak, but is also efficient to remove wires, longlines and trawls. The Swedish retrieval method is of smaller scale and is adapted to the shallow waters in the Baltic Sea and Øresund. Both methods or an intermediate method may prove the best solution for Skagerrak. In figures 1 and 2 the Norwegian and the Swedish retrieval gear is illustrated. Nets Figure 1 Retrieval gear used by The Norwegian Directorate of Fisheries (Furevik, in MC Mullen & al 2004). Source: Directorate of Fisheries, Norway Figure 2 Retrieval gear used by The Marine Research Institute of Sweden Source: Institute of Marine Research, Sweden The Retrieval Surveys have shown that it is possible to pick up lost nets with reasonable good efficiency. The experience from the surveys does show that it is important to have good information on the amount of gear lost and the positions where they are lost. It is also important to do the surveys at a time of the year when good weather can be expected as the efficiency of the retrieval equipment is reduced in bad weather. Figure 3 Cod caught in ghost net (from Swedish retrieval survey) Figure 4 Some of the lures that was entangled to retrieved fishing gear Source: Institute of Marine Research, Sweden Source: Institute of Marine Research, Sweden Figure 5 Some of the catches from retrieval surveys in the Baltic Sea Source: Institute of Marine Research, Sweden Figure 6 Ghost nest retrieved by a Scottish trawler in 2004 Source: Directorate of Fisheries, Norway Figure 7 Removing dead fish from ghost nets Source: Directorate of Fisheries, Norway Further reading Norwegian pages: Information from the Norwegian Directorate of Fisheries (Norwegian and English) http://www.fdir.no/fiskeridir/ressursforvaltning/rapporter_utredninger/tapte_redskap/ garnopprydning_utenfor_norge_og_irland Information brochure on how to avoid loosing fishing nets (in Norwegian) http://www.fdir.no/fiskeridir/tall_og_fakta/brosjyrer_og_faktaark Other relevant information (in Norwegian) http://www.imr.no/__data/page/4081/Nr.1_2002_Tapte_garn_er_en_internasjonal_utfordring.pdf http://www.fiskerifond.no/files/projects/attach/343024taptefiskegarn.pdf EU-pages: UK factsheet www.jncc.gov.uk/page-1567 Institute for European Environmental Policy, report on Ghost Fishing by Lost Fishing Gear http://www.ieep.eu/publications/pdfs/2005/ghostfishing.pdf Baltic states project www.balticseabreeze.org/documents/Kampanjer-och-aktiviteter/Baltic_SeaBreeze/ Pressmeddelande_Kleipeda.pdf Contacts Norwegian Directorate of Fisheries, www.fiskeridir.no, Phone: +47 55 23 80 00 The Swedish Board of Fisheries, www.fiskeriverket.se, Phone: +46 31 743 03 00