Fishers have been complaining about the effects of bottom trawl gear on the marine environment since at least the 14th century. Trawl gear affects the environment in both direct and indirect ways. Direct effects include scraping and ploughing of the substrate, sediment resuspension, destruction of benthos, and dumping of processing waste. Indirect effects include post-fishing mortality and long...

The density, size composition and growth of Nephrops norvegicus were examined at six sites in part of the Firth of Clyde, SW Scotland, between 1990 and 1992. Sampling was carried out using small mesh trawls and by an underwater television camera. The growth of male Nephrops at each site was investigated by analysis of length–frequency distributions using the computer program ‘‘Multifan’’. Estim...

The diets of gurnards Aspitrigla cuculus and Eutrigla gurnardus, lesser-spotted dogfish Scyliorhinus canicula and whiting Merlangius merlangus were examined to determine whether they migrated into recently trawled areas to feed on animals that may be damaged or dislodged by the action of a 4 m beam trawl. Gurnards and whiting increased their intake of prey after an area had been fished. In part...

the catch composition of the bottom trawl fishery along the coasts of karataş was evaluated in the 2002-2003 fishing season. a total of 110 species were registered, the fishes showed the highest diversity (90 species) followed by 15 crustaceans species and 5 species of cephalopods. the highest catch per unit effort (cpue) value (66.8 kg h -1 ) was recorded in september when the fishing season w...

The system of computer-aided design industrial fishing gear (CAD-FG), developed by the small innovative enterprise Digital Technologies Laboratory LLC with support FASIE, is an import-substituting product for manufacturers and designers bottom mid-water trawls. At present stage trawl operation, use CAD-FG on vessels will ensure correct setting (trawl doors, hydrodynamic shield, loading chain, e...

species composition, relative abundance, absolute abundance and biomass of sturgeon species were studied during the years 2008-2009. eighty five stations were covered in the stratified random sampling design in depths less than 1om using 9m bottom trawl (head line) and in depths more than 10m using 24.7m bottom trawl (head line). more than 70 specimens of acipenser persicus were caught during t...

Short-term effects of bottom trawling on a 'hard-bottom' (pebble, cobble, and boulder) seafloor were studied on the outer continental shelf in the eastern Gulf of Alaska. Eight sites were trawled in August 1996; then, from a research submersible we videotaped each trawl path and a nearby reference transect to obtain quantitative data. Boulders were displaced, and large epifaunal invertebrates w...