Life cycle assessment of horse mackerel fisheries in Galicia (NW Spain): Comparative analysis of two major fishing methods

Atlantic horse mackerel Trachurus trachurus) is one of the main target pelagic species of the coastal purse seining and bottom trawling Galician fleets. The goal of this LCA study was to assess and compare the environmental impacts associated with the fishing operations related to Atlantic horse mackerel extraction in these two Galician coastal fisheries. This analysis included the operation of the vessels, together with major inputs related to the production of diesel, fishing nets or anti-fouling paints. Data regarding vessel operation was obtained from the questionnaires filled out by a total of 54 skippers. Results showed that environmental burdens regarding horse mackerel landing are associated mainly with activities related to diesel production, transport and consumption of the fishing vessels. Furthermore, cooling agent leakage from the cooling chambers was identified as a major impact regarding ozone layer depletion and global warming potentials. Horse mackerel captured by purse seiners presented reduced environmental burdens for all impact categories respect to horse mackerel landings by bottom trawlers. The environmental reduction ranged from 49 to 89%, depending on the impact category analyzed. Discard rates for coastal trawlers were also identified as a major environmental impact in this fishery. Revision of fishing quotas and fishing strategies for the horse mackerel fishery and reduction of energy consumption, through the introduction of new alternative fuels or technological actions, are necessary in order to reduce the environmental impacts of a highly fuel-dependent activity.