Impacts on fisheries

Extra facts

• Changing geographic distributions of fish species are expected—namely, poleward expansions of warmer-water species and poleward contractions of colder-water species (Beare et al. 2004a; 2004b).
• New fish habitats may emerge from polar ice melts (Easterling et al. 2007).
• In coastal regions, sea level rise, surges and flooding could have both negative and positive impacts on fish productivity (Easterling et al. 2007).
• Climate change can directly impact fish physiology, potentially changing feeding, migration and breeding behavior (Brander 2010).
• Changes in the physical environment (e.g. temperature) of fish can alter their growth, reproductive capacity, mortality and geographic distribution (Brander 2010).
• Indirect climate change effects alter the productivity, structure and composition of the marine ecosystems that fish rely on for food (Brander 2010).
• Coral reefs’ potential vulnerability to ocean warming and acidity presents serious food security concern to countries, such as Solomon Islands, that heavily depend on reef fisheries (CCAFS 2012).
• Quantitative projections for impacts on marine and inland aquaculture aren’t available yet, but there is hope that aquaculture will be a major source of animal protein under climate change in the future (Cochrane et al. 2009).
• However, inland aquaculture (raising of fish in captivity) is likely to be affected by water scarcity or flooding and salinization in coastal regions (Brander 2010).

Methods, caveats and issues

Assumptions

In all marine ecosystems, climate effects will not be independent of changes in abundance and distribution induced by fishing, making it especially difficult to assess the relative effects of climate on population distribution in the short-term (Jennings and Brander 2010).

Sources

• Beare DJ et al. 2004. Observations on long-term changes in the prevalence of fish with sourthern biogeographic affinities in the North Sea. Marine Ecology Progress Series 284:269-279.
• Beare DJ et al. 2004b. An increase in the abundance of anchovies and sardines in the north-western North Sea since 1995. Global Change Biology 10(7): 1209-1213.
• Brander K. 2010. Impacts of climate change on fisheries. Journal of marine systems 79:389-402.
• Thornton P, Cramer L, eds. 2012. Impacts of climate change on the agricultural and aquatic systems and natural resources within the CGIAR’s mandate. CCAFS Working Paper 23. Copenhagen: CCAFS. (Available from http://cgspace.cgiar.org/handle/10568/21226)
• Cheung WWL, Lam VWY, Sarmiento JL, Kearney K, Watson R et al. 2010. Large-scale redistribution of maximum fisheries catch potential in the global ocean under climate change. Global Change Biology 16:24–35.(Available from http://www.seaaroundus.org/researcher/dpauly/PDF/2010/JournalArticles/LargeScaleRedistributionOfMaximumFisheriesCatchPotential.pdf)
• Cochrane K, De Young C, Soto D, Bahri T. 2009. Climate change implications for fisheries and aquaculture: overview of current scientific knowledge. FAO Fisheries and Aquaculture Technical Paper no. 530. Rome: [FAO] Food and Agriculture Organization of the United Nations.
• Easterling WE, Tubiello FN, Aggarwal et al. 2007. Food, fibre and forest products. In: Parry ML, Canziani OF, Palutikof JP, Van Der Linden PJ, Hanson CE, eds. Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge: Cambridge University Press.
• [FAO] Food and Agriculture Organization of the United Nations. 2008. Climate change for fisheries and aquaculture. Technical background document from the expert consultation held on 7-9 April 2008. Rome: FAO. (Available from ftp://ftp.fao.org/docrep/fao/meeting/013/ai787e.pdf)
• Jennings S., Brander K. 2010. Predicting the effects of climate change on marine communities and the consequences for fisheries. Journal of Marine Systems 79:418-426.