Barents Sea - Exploitation

The anthropogenic driver with the largest documented effects on the Barents Sea ecosystem is currently fisheries. Negative impacts of fisheries include overfishing of several of the smaller stocks and damage to benthic communities caused by bottom trawling. However, previous overexploitation, illegal catches and discards are since 2006 significantly reduced and is by 2013 not regarded as a problem. However, climatic changes have considerable effects on the system. Within ICES the Arctic Fisheries Working group asses the development of selected species and make recommendations for fisheries quotas (Anon 2012). The climate changes likely represent both natural variations and effects of anthropogenic emissions of CO2 and other greenhouse gases. The relative importance of these two sources is not completely understood. Reproductive failure and negative population trends in ice-dependent marine mammals are possible effects of climate change. The Barents Sea is presently a relatively clean ocean with respect to pollution, however, it receives long-range transboundary transported pollution through advection, in particular PCBs and other persistent organic pollutants as well as some inorganic contaminants (e.g., Hg and Pb). These substances are detectable in biota, but to date significant effects are limited to top predators, such as polar bears and glaucous gulls. Other transboundary contaminants found in the Barents Sea area are radioactive substances. Their present concentrations are too low to have any impact on marine organisms, but risk of significant contamination exists from local sources. Oil and gas activities and ship transport have thus far had no significant direct impact on the ecosystem, but this may change with the expected increase in the level of activity in the future. Ocean acidification caused by anthropogenic emission of CO2 is an emerging problem that might have a large impact on the Barents Sea ecosystem in the future.