U.S. President Donald Trump has made no secret of the fact that when environmental science clashes with commercial interests — whether it’s coal mining or climate change — he’ll ignore the science. A shock discovery off the coast of eastern Canada shows just how dangerous that can be, certainly when it comes to fishing policy. And Canada, to be clear, set out to respect scientific findings in its policy.

A year ago, Canada’s Department of Fisheries and Oceans took a hard look at supplies of Northern cod in Newfoundland and decided to allow more fishing. I had been encouraged at the time that the Canadians seemed to be making policy based on caution and good science. Cod supplies had made an impressive recovery over the past decade, helped by strong fishing restrictions.

But a recent government survey showed that cod numbers dropped by 30 percent in the past year, with losses projected to grow over the next two years. The setback comes after a decision early in 2017 to allow a lot more fishing, although other environmental factors — a drop in the number of capelin, a key cod food source — also played a role.

The new policy went directly against scientists’ warnings that the cod recovery remained fragile. Another two years of fishing at anything like least year’s levels could wipe local cod out entirely, ecologist Sherrylynn Rowe, a leading cod expert at the Memorial University of Newfoundland, told me in an interview.

That would be a true disaster, especially following 25 years of cautious and well-considered policy. It would also destroy the encouraging regrowth of an industry that once employed nearly one of every eight people in Newfoundland and Labrador.

Last year’s fateful decision reflected the eagerness of the fishing industry to ramp up production, following years of good news about the cod recovery. In 2016 and 2017, the government largely adopted proposals made by a lobby set up by fishermen, plant workers and food processors to push for the rapid restoration of a larger industry. This year, following the new supply figures, the group has proposed a slightly shorter fishing season, but no hard fishing quotas. That’s pretty short-sighted, given the risks.

Fortunately, parts of the broader fishing industry are now pushing for more aggressive action. The Groundfish Enterprise Allocation Council (GEAC), for example, a group representing a number of big Canadian cod processors and harvesters, wants the allowed take be cut in half. That would be more in keeping with the Canadian government commitment to follow the precautionary principle in managing the cod recovery, which requires them to always err on the conservative side. But pressure from the fishing industry was significant and the government convinced itself it was indeed being cautious.

A decision on policy for 2018 should come soon, and bold action could still get the recovery back on track. Humans should sensibly control the one thing they can, reducing total catches and hoping for the best. But it’s becoming clear that the future of fishing for wild cod in Newfoundland is going to need more than good science. It will also take some creative business models based on catching far fewer fish by historical standards. Encouragingly, there may be ways that could happen, while still supporting local fishing communities.

One way is to shift back to less industrial fishing methods. Since 2015, for example, a fishery on Fogo Island — the largest offshore island in Newfoundland and Labrador — has moved to paying fishermen twice the price they can normally get for cod, on condition that they catch the fish using single lines, rather than industrial net-based methods. Tony Cobb, a co-founder of the fishery, told me that at normal prices, fishermen can only survive by increasing the number of fish they take. But single line fishing doesn’t damage the cod flesh like industrial fishing methods do, and the fish then attract much higher prices. More than 50 fishermen have chosen to fish for Fogo Island Fish, as they can make more money catching fewer fish.

Basing environmental policy on good science is a start. But it will take more. In Canada’s case, it will mean turning away from the industrial-scale model of fishing, if they’re to find a way to let both fish and fisherman survive. It’s a cautionary tale other fishing nations could learn from.

Mark Buchanan, a physicist and science writer, is the author of the book “Forecast: What Physics, Meteorology and the Natural Sciences Can Teach Us About Economics.”

KEYWORDS Canada, fishing, cod