Silent damage and rays of hope: Nick Dulvy sheds light on ecological diversity in the world’s oceans

Simon Fraser University Distinguished Professor Nick Dulvy has dedicated his research career to illuminating the diversity of species that make the ocean their home.

Through over twenty years of international collaboration, Dulvy has emerged as a world-leader in the field of marine ecology, and his work has garnered honours in Canada and abroad, including Fellowship in the Royal Society of Canada, Le Cren Medal from the Fisheries Society of the British Isles, and the Henry Messel award for Conservation Leadership.

“I have always been mystified by the thin silvery veneer that separates our world from the underwater world and the fishes that dominate this mysterious world beneath,” he says. As he dove into marine research, he found an incredible wealth of life living in the ocean, much of it under-studied and under threat.

“My key contribution has been to shed a light on the silent damage that overfishing is doing to the oceans,” Dulvy says. His approach combines traditional natural history approaches such as field guides, thermometers, microscopes and dissection kits alongside big-data approaches to better understand species’ population growth rates and global extinction risk patterns.

“Overfishing is permanently altering marine biodiversity and ecosystem function across the world’s oceans,” Dulvy says. “We now know that over one-third (37.5%) of sharks, rays, and chimaeras are threatened.”

This global decline in shark populations has happened alarmingly fast. Oceanic populations have plummeted by as much as 71 per cent in the last 50 years. Many sharks are long-lived and slow to mature. Once depleted, their populations can take a long time to recover, if they recover at all.

The research paints a bleak picture, but there are some rays of hope. His 2023 paper found that some shark populations have stabilized, or are growing, in the North Atlantic thanks to improved regulation, enforcement and monitoring of fisheries.

“Our work has been a wake-up call that has resulted in global regulation of the shark fin and gill plate trade,” he says. Critically, we have shown that that damage done can be reversed by eliminating overfishing.”

“We now know which species to focus conservation on and which threats to address; we also know which countries to work with to improve the conservation status of these iconic fishes.”

Turning the tide for the world’s oceans requires an international effort, which is why Dulvy has sought out a diverse, international group of collaborators to build consensus around conservation priorities and approaches. “Coauthors are ambassadors carry this knowledge to government offices and change-makers all over the world,” he says.

“Sharks and rays are the canary-in-the-coal mine of overfishing. If we can fix overfishing of sharks and rays this will eliminate many of the problems of modern fisheries, and ensure larger fisheries catches and income far into the future.”