FAO Fisheries & Aquaculture
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Food and Agriculture Organization of the United Nations Fisheries and for a world without hunger Aquaculture Department Fishing Gear Types Lift nets Lift nets ISSCFG code: 05 Characteristics Overview Lift nets are horizontal netting panels or bag shaped like a parallelepiped, pyramid or cone with the opening facing upwards which are submerged at a certain depth, left for a while, the time necessary for light or bait to attract fish over the opening, then lifted out of the water. Three main type of lift nets can be distinguished: portable hand lift nets (used, in general, with light attraction), shore operated stationary lift nets. Handling Equipment Lift nets are hauled out by hand or mechanically through bomm(s) and blocks. The handling (setting and hauling) of large lift nets, normally requires, in addition, one or several winches. Vessel Overview Boat-operated lift nets are often used, in small-scale fisheries, from small catamans (e.g. in inland fisheries, in Africa) or two canoes operating together; other models of lift nets, larger (i.e. bag nets, "basnig", in Asia) are handled, from large vessels, known as Lift netters. In some other cases no boats are required (for shore stationary installations). Fish Operation The operations, from the shore, from a canoe or a bigger boat, include - the setting of the net at a certain depth, opening facing upwards; - the attraction of the fish over the above mentioned opening, by light or bait; then, - the lifting/hauling of the net out of the water, by hand or mechanically. Target Species Small pelagic species, fish and squid. Water Area Overview All over the world. Gear Environment Lift nets are, in general, active a few meters below the surface; when light attraction is used, the active depth depends on the attraction power of the light; this differs much if lamps (one or several) are above the surface or if under-water lamps are used; with the former, the power of the lamp and the number of these is the criteria; with the later, things depend on the length of the under-water power cable to the lamps); either in sea and inland waters. Impacts Species The impact of the use of lift nets depends on how selective is the attraction above the lift net opening, mainly attraction to the light. Certain species or smaller sizes of fish can be attracted, at the same time, in addition to target species (a bycatch which is some time discarded). FAO Fisheries and Aquaculture Department Socio-economic It is also worth mentioning in respect to the use of light attraction with lift nets for squid fishing, that, in far east Asia, with the steep increasing of the power of lights, a decrease of the effectiveness of each individual liftnetter fishing in fleets, not so far one to each other, has been observed. FAO Fisheries and Aquaculture Department.