Warming planet to affect life in the coldest ocean depths

The Common Oceans Deep-Sea Fisheries Project is extending its support and expertise to regional fisheries management organizations (RFMOs) as they prepare for future impacts of warming seas.

Climate change will cause environmental and biological changes even in the coldest, deepest and remotest parts of the ocean in time affecting fish stocks and livelihoods of deep-sea fishers.

Four RFMOs: the Northwest Atlantic Fisheries Organization, the North-East Atlantic Fisheries Commission, The North Pacific Fisheries Commission and The South Pacific Regional Fisheries Management Organisation have recently adopted climate change resolutions to explore and address impacts on target fish stocks, related species and the wider ecosystem.

Reports for each of these RFMOs by independent scientists commissioned by the Deep-sea Fisheries Project are now proposing the next steps. The reports were discussed with the RFMOs in an online workshop.

All four consultancies agreed that there will be physical and chemical changes in the oceans, including temperature and acidity changes, reduced dissolved oxygen levels, and an increase in frequency and duration of extreme weather events. 
At a biological level, this will result in changes in the production of microscopic plants and animals that feed the rest of the food web, changes in species distributions, and changes in the sizes, age of maturity and reproductive potential of different species. 

Science and management

“RFMO scientific committees will likely need increased human and financial resources to be able to predict changes in fish distributions, the impacts of these on the wider food web and ecosystem,” said Tony Thompson, Common Oceans senior deep-sea fisheries expert.

“Species most at risk of climate change will need to be identified to produce “climate-informed” management advice. This is so complex that the interactions can only be appreciated through the development of advanced mathematical and computer models.”

Decision-makers who sit on the RFMO management committees will need to actively support  actions for climate change adaptation and response, the scientists found. 

This will mean considering the adoption of a climate-change roadmap, which outlines immediate tactical actions and longer-term strategic actions. For the management of target stocks, there is a need to consider how distributional changes will affect quota allocations. These distributional shifts may also mean that fishing will need to take place in areas currently not fished, the ecosystem impacts of which will need to be considered. Extreme weather events will require the need for a flexible management response, for which both long-term forward planning and a short-term response will be necessary.

Workshop participants highlighted the need to build capacity on climate change adaption and response in RFMO management committees, improved communication among scientists and managers, and guidance for the development of RFMO climate change roadmaps in order to act on their climate change resolutions. They reiterated the incredible value of cross-RFMO dialogue to share challenges and brainstorm solutions.

Interested individuals who would like to access the DSF Project climate change consultancy reports and other relevant resources are invited to join the Deep-sea Fisheries Project online technical forum here.