This study was prepared as part of the FAO Fishery Industries Division's Regular Programme 2.3.3. Fisheries Exploitation and Utilization. It presents a critical evaluation of the methodologies used in impact studies, and uses it to make conclusions about what lessons have been learned to date on how benthic communities are affected by towed-gear fishing activities.
This review focuses on the most recent studies (i.e. those of the last 15 years) to investigate the physical and biological impacts of towed fishing gears on benthic habitats and communities. It covers otter trawls, beam trawls and scallop dredges, but not hydraulic dredging because this activity is very distinctive in terms of both the way its operates (through the direct removal of sediment) and the fishing ground that it affects (the intertidal zone). The report is organized in three main sections: methodologies, physical impacts, and biological impacts. Gear type and the nature of the sea bed are two factors that seem to have a great influence on the level of disturbance caused by fishing activity (Collie et al., 2000). Thus, the sections on physical and biological impacts are separated into subsections on gear (otter trawl, beam trawl and scallop dredges) and bottom type (soft bottom and hard bottom with erect structures).
