11th September 2018

Ocean farmers need to plan ahead to thrive

Get the latest news

The next generation of aquaculture farmers need to be prepared for climate change as a matter of urgency, according to a study.

Aquaculture, where fish and other aquatic species are cultivated, is the fastest growing food sector and will involve many of the world’s future farmers.

Researchers from the National Center for Ecological Analysis and Synthesis (NCEAS) at UC Santa Barbara have published analysis of how climate change could affect marine aquaculture production, specifically of finfish and bivalves (e.g., oysters), across the globe.

The study, published in the Nature Ecology and Evolution journal, highlights that climate change is not only a threat to global production in the future, but is also affecting today’s producers.

Halley Froehlich, lead author and postdoctoral researcher at NCEAS, said: “Climate change is impacting marine aquatic farmers now, and it’s likely to get worse for most of the world if we don’t take mitigating measures.

“There’s a lot of push for ‘blue growth’ in aquaculture in both developing and developed regions, but less effort has gone into how to develop adaptive measures under climate change, mostly because we do not have a good sense of the level or location of impacts. Our study begins to shed light on these unknowns.

“Aquatic farmers are on the frontlines of climate change. Some are already seeing the effects and know they need to be prepared for what’s to come. But that’s going to take planning by not only the farmers, but governments too.”

The analysis provides a crucial first step in helping ocean farmers and coastal countries prepare for the coming changes and to ensure sustainable seafood production worldwide.

Now aquaculture’s contribution to global seafood production surpasses that of wild-caught fisheries, according to the newest State of World Fisheries and Aquaculture report by the United Nations’ Food and Agriculture Organization (FAO).

The authors found that coastal countries should expect their overall potential for aquaculture production to decline over time, as water temperatures rise and oceans undergo other shifts due to a changing climate.

What is more, the region that currently accounts for 90 per cent of the world’s total production – Indo-Pacific countries such as China, Bangladesh and Indonesia – will likely feel the biggest impacts as they depend more heavily on seafood for sustenance and farming for livelihoods than the rest of the world.

Ben Halpern, director of NCEAS and a professor at UCSB and co-author, said: “The issue is less about whether or not we will be able to grow enough fish in the ocean under a changing climate globally — we can — and instead about who wins and who loses, and by how much.

“Climate change will likely have highly inequitable consequences among ocean farmers. Governments provide permits and leases for growing different species and setting those locations now with the future in mind will help avoid putting things in riskier places.

“If you were a land farmer, would you want to buy property that will be plagued by drought in 15 years? I doubt it. The same thinking should be applied to ocean farming.”

One strategy to help ocean farmers adapt will be to have farms in more favorable ocean patches. Ms Froehlich believes good planning now could help marine aquaculture adapt to change while enabling ocean planners to balance aquatic farming with the many other uses of oceans, including wind energy and conservation.

“The industry is still in its growing phase, and that allows some flexibility,” she said.

This flexibility could help countries with large Exclusive Economic Zones (EEZs), such as the United States, since having more ocean space to move farms could lessen a lot of the threat. Already, there are reports of U.S. oyster farmers moving their hatcheries away from the acidified waters of the Pacific Northwest, Ms Froehlich said.