Fisheries and climate

Fish stocks and the fisheries based on them have always experienced variability due to climate. Changes in temperature, salinity, winds, ocean currents, oxygen, and other factors affect their distribution, growth, survival, and recruitment. Examples of such effects are given for several regions of the oceans and the processes are described.

Poleward distribution shifts have occurred since the 1960s and can be attributed to the effects of anthropogenic climate change with a high degree of confidence. In addition to climate effects, fisheries are subjected to other anthropogenic stresses, including high fishing mortality, loss of habitat, pollution, and introduction of alien species.

These interact and may reduce the resilience of exploited stocks, although climate change may also increase productivity in some cases. Fisheries production depends on primary production, but to date we have low confidence in our ability to predict how this will change over time under different climate scenarios.

Past changes in the distribution and productivity of fisheries, caused by climate variability, have had a major impact on human communities which were dependent on them.