'Climate change affects everything': Farmed seafood supply at risk if no climate action is taken, B.C. study suggests

Mussels are seen in this undated image. (Shutterstock)

New research from the University of British Columbia has found that the farmed seafood supply could be at risk if no action is taken to address climate change.

The new modelling study, which was released Monday, claims that farmed seafood supplies, which include salmon and mussels, will drop 16 per cent before the end of the century if nothing is done to mitigate climate change.

The study examined approximately 70 per cent of the world’s marine farming, as of 2015. It also focused on exclusive economic zones, which are where most of the world’s seafood farming takes place.

Many factors such as changing ocean temperatures, the supply of fish oil and suitable mariculture areas in the future were also taken into account during the study.

The findings suggested that the marine farming industry is very vulnerable to the effects of climate change.

“Ocean-farmed seafood or mariculture is often seen as a panacea to the problems of depleted stocks of wild fish and growing human demand, and is expected to grow substantially in the coming years,” said lead author Dr. Muhammed Oyinlola, a postdoctoral research fellow at the Institute for the Oceans and Fisheries.

Researchers said climate effects on marine farming can include changes in the areas where fish are farmed, as well as the food used to feed them.

For example, researchers said fish farms tend to use fishmeal and fish oil, which are largely made up of smaller fish such as herring and anchovy that are also being threatened by climate change.

“Some regions produce more bivalves, such as mussels, oysters and clams, and in these regions, the impact is smaller,” Dr. Oyinlola said. “In regions that produce more finfish, such as salmon, the impact will be high due to reduction in the supply of fishmeal and fish oil.”

Researchers said under the current carbon emission rates, finfish farming is projected to decrease globally by three per cent by 2050 and 14 per cent by 2090. Countries where finfish production is more prominent include Norway, Iceland, Finland, Chile and Bangladesh.

For areas where farming for mussels and clams is more common, including here in Canada, researchers said the industry will remain more stable. Researchers said that farming is projected to increase by 2050 and decrease by 2090 under both climate scenarios.

However, researchers said in a low-emissions scenario where action is taken to address climate change, marine farming could grow by about 17 per cent by the mid-21st century and by about 33 per cent by the end of the century.

The study also found that substituting fishmeal and fish oil for plant-based foods such as soybeans, could help alleviate the impacts of climate change on fish farms.

Researchers said when a quarter of fish food was substituted with alternatives, under a low-emissions scenario, marine farming was projected to increase by 25 per cent by 2050 and 31 per cent by 2090.

“While there is enthusiasm about ocean (farming) helping to increase the production of seafood, the study shows if humans don’t relieve climate change, such enthusiasm will be tempered,” said senior author Dr. William Cheung, IOF professor and director. “Climate change affects everything, including aspects of seafood farming we’ve not previously considered. We need to act, and quickly, to mitigate climate change rather than rely on one solution to solve all our seafood production problems.”