Fisheries Impacts on North Atlantic Ecosystems: Catch, Effort and National/Regional Data Sets
Energy Consumed by North Atlantic Fisheries
Peter Tyedmers
School for Resource and Environmental Studies, Dalhousie UniversityAbstract
As part of the Sea Around Us project at the University of British Columbia, research was undertaken to quantify the fuel energy consumed by North Atlantic fisheries. Where possible, this included evaluating both the contemporary situation and changes in direct fuel inputs to fisheries over time. Two distinct methods were employed in estimating both the total fuel consumed and the energy intensity of specific fisheries and fishing fleet sub-sets. The first method involved soliciting relevant data directly from fishing companies. The second technique combined estimates of the generic rates at which fishing vessels consume fuel in relation to their main engine horsepower, as derived from real-world vessel performance data, with detailed catch and fishing effort data. Ultimately, a total of 58 analyses were conducted representing 54 distinct North Atlantic fisheries or fleet sub-sets. Based in five countries, these 54 fisheries together accounted for total annual landings, as of the late 1990s, of over 5.2 million live weight tonnes of fish and/or shellfish, and encompassing a range of fishing gears, vessel sizes and primary target species. Moreover, for almost half of the fisheries analyzed, time series estimates of energy intensity and total fuel consumption were possible for periods ranging up to 21 years. For the most recent years in which data were available, the results indicate that these 54 fisheries together consumed just over 1 billion litres of fuel annually. Amongst the 29 groundfish fisheries analyzed, energy intensities ranged from a low of 230 litres/tonne to just over 2,700 litres/tonne. When taken together, however, these 29 fisheries experienced a mean energy intensity of about 510 litres/tonne of groundfish and associated bycatch species landed. In contrast, amongst the twelve fisheries targeting small pelagic species analyzed, contemporary energy intensities ranged from 19 to 159 litres/tonne of fish landed and averaged just 62 litres/tonne. The single relatively small fishery for large pelagic species analyzed had an energy intensity of 1,740 litres/tonne of tuna and swordfish landed. Amongst the invertebrate fisheries evaluated, the average energy intensity of the eight fisheries targeting shrimp was 918 litres/tonne while the two scallop fisheries had an average energy intensity of just 347 litres/tonne landed, and the single crab fishery evaluated had an energy intensity of about 330 litres/tonne. Finally, the lone fishery for Norway lobster analyzed, had an energy intensity of 1,025 litres/tonne of total landings.