Climate change is an imminent threat to much of the Earth’s biodiversity. Approximately 90 per cent of global warming is happening in the ocean, but the full extent of these impacts on marine species is not fully understood.
Dr. Daniel Boyce, a research consultant with the United Nations and adjunct professor at Dalhousie University, is working with the Ocean Frontier Institute (OFI) and Oceans North to better understand how climate change is impacting Canada’s marine species. OFI provided funding for the research as part of the research program Safe and Sustainable Development of the Ocean Frontier, which is funded in part by the Canada First Research Excellence Fund.
Initial research shows that nearly half of fish stocks are at risk due to the effects of climate change.
His work, which was recently published in the journal npj Ocean Sustainability, aims to provide a framework to support policymakers in their conservation efforts and fisheries management strategies.
The Northwest Atlantic: a climate hotspot
Year-round temperate waters are vital to maintaining ecosystems like eelgrass meadows and kelp forests. The Northwest Atlantic Ocean reached an alarmingly warm temperature in the summer of 2023, averaging 1.3 degrees Celsius above normal. This was one of the most extreme temperature anomalies on record.
Researchers are becoming more aware of how climate change is impacting life underwater. As the water warms and becomes more acidic, it impacts species of all shapes and sizes. Entire ecosystems are being fundamentally changed, creating uncertainty for fishermen.
More than 24,000 residents in Canada’s Atlantic provinces rely on fishing for their livelihoods, making fisheries management vital to the success and longevity of the local fishing industry, as well as the marine ecosystems in which they operate.
Dr. Boyce and his colleagues set out to quantify the risk that climate change poses to marine species in the Northwest Atlantic.
Assessing the impact of climate change on fisheries
Dr. Boyce and his colleagues developed a framework called the Climate Risk Index for Biodiversity (CRIB) to assess Atlantic marine species. It acted as a report card to evaluate how vulnerable each species was to the impacts of climate change. This unique methodology incorporates the past, present, and future into its assessment.
“We notice that there are a lot of climate impact studies out there that aren’t being applied to day-to-day conservation and fisheries management,” says Dr. Boyce. “We developed this approach as a way of bridging that gap and helping decision makers evaluate risk to support conservation under climate change.”
To best support fisheries management, the researchers focused their efforts on 90 fish stocks of economic interest to Atlantic Canada. When considering the high greenhouse gas emission scenario, they found that almost half of the stocks face a high or critical climate risk. Furthermore, some of the most at-risk species were found to be in the Gulf of St. Lawrence, where much of human activity occurs and marine habitats reside.
“We found that the climate risk tended to be higher in waters that support most of our fisheries catch in Canada. With continued high emissions, the species that we actively fish have a three times higher climate risk exposure,” says Dr. Boyce.
When focusing on harvested species, over two-thirds were at a high climate risk. Species such as lobster, crab, shrimp, and scallops account for over 80 per cent of the total value of all the seafood in Atlantic Canada once it is received by the buyer, but these species are projected to experience the highest climate risks over the next 75 years.
Although the projections were grim for a high emissions future, the number of species at risk significantly decreased under a scenario with low emissions.
Creating a sustainable ocean
A changing ocean requires the development of new management strategies. Policy makers depend on reliable research to best inform their decisions.
“Our actions as a society in the coming years will have a huge effect on our marine fisheries and the communities that rely on them,” says Dr. Boyce. “If we can alter our behaviour and reduce our emissions, this negative outcome can potentially be avoided.”
Dr. Boyce and his colleagues are hoping to develop an online platform to showcase the research results. His goal is to break down the barriers between academia and the public, providing accessible and accurate scientific information for all to utilize.
“We observed that there were hundreds of climate vulnerability and risk studies out there, but so few were being used in decision-making,” says Dr. Boyce. “We wanted our research to be easily communicated and better able to be used in conservation by decision makers.”
The team hopes that their research will be used to better inform fisheries management strategies, and Dr. Boyce plans to continue exploring how the CRIB framework can be used to support climate-resilient fisheries in Canada.
