Future fisheries can expect $10 billion revenue loss due to climate change

The authors used a species distribution model and applied this to the 887 marine fish (which represents 60% of global average annual catch in the 2000s) and invertebrate species in the world oceans under high and low emissions scenarios. The authors find that global maximum catch potential (MCP) is projected to decrease globally by 7.7% between 2010 and 2050, under the business as usual scenario, and the global revenue from this is predicted to decrease by 10.4% compared to 2010. Under the low emissions scenario, MCP is projected to decrease globally by 4.1% and revenue by 7.1%.

Global marine fishery landings have been estimated between 80 and 85 million tonnes per year since 1990, and this figure is thought to be an underestimate due to significant unreported catches. The global fishery industry directly or indirectly supports the livelihood of 10-12% of the world’s population and is increasingly threatened by climate change.

Importantly, the MRP (maximum revenue potential) in these different emissions scenarios varies in different latitudes and ocean basins; impacts on the tropics will be the greatest with MCP and MRP decreasing by 38% and 33% under the high emissions scenario. Not all impacts are predicted to be negative, however; in the Arctic Ocean and the Northern Atlantic the MRPs are projected to increase by 71% and 100%+ respectively; these areas are currently limited by ice cover but as this reduces, the area available to be fished expands.

Percentage change in fisheries MRP in different ocean basins at different latitudes

Climate change is predicted to have negative effects on the MRP of 89% of the world’s fishing countries (170 countries), many of which are coastal low-income countries whose populations are dependent on fisheries for nutritional needs.

Aquaculture expansion has been viewed as a mitigation option to counteract declining fishery stocks, but here the authors’ results suggest that the negative impact on MRP under the “faster aquaculture expansion” scenario is higher than the change under the “constant price” scenario (they do not offer a clear explanation of why this might be though). This suggests the need to carefully consider development of aquaculture as a way to adapt to climate change impacts on marine capture fisheries

Abstract

Previous studies highlight the winners and losers in fisheries under climate change based on shifts in biomass, species composition and potential catches. Understanding how climate change is likely to alter the fisheries revenues of maritime countries is a crucial next step towards the development of effective socio-economic policy and food sustainability strategies to mitigate and adapt to climate change. Particularly, fish prices and cross-oceans connections through distant water fishing operations may largely modify the projected climate change impacts on fisheries revenues. However, these factors have not formally been considered in global studies. Here, using climate-living marine resources simulation models, we show that global fisheries revenues could drop by 35% more than the projected decrease in catches by the 2050 s under high CO2 emission scenarios. Regionally, the projected increases in fish catch in high latitudes may not translate into increases in revenues because of the increasing dominance of low-value fish, and the decrease in catches by these countries’ vessels operating in more severely impacted distant waters. Also, we find that developing countries with high fisheries dependency are negatively impacted. Our results suggest the need to conduct full-fledged economic analyses of the potential economic effects of climate change on global marine fisheries.

Reference

Citation: Vicky W. Y. Lam, William W. L. Cheung, Gabriel Reygondeau, U. Rashid Sumaila. Projected change in global fisheries revenues under climate change. Scientific Reports, 2016; 6: 32607 DOI: 10.1038/srep32607

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