Salmon face global warming threat
Mark MacKinnon, Toronto Globe & Mail, Jan. 28, 2000
Ottawa -- The Fraser River fishery could be almost barren of salmon within a few decades if water temperatures continue to rise because of global warming, a new report says.
Canada's largest salmon fishery could be the first tangible casualty of climate change, according to the report, prepared for the federal government by a group of scientists, academics and bureaucrats. It says even a small change in the river's temperature could destroy spawning grounds.
"If summer temperatures go a degree or two higher most of the spawning fish will die, causing a collapse of the salmon resource in the system," the report says.
While Canada's average surface temperature has warmed only about one degree over the past century, some climate models forecast a global warming of three to five degrees over the next 50 years, if current energy consumption patterns aren't changed.
Temperatures in the Fraser River have been rising gradually for years, and now regularly reach as high as 22 degrees in the headwaters in the summer. That's "approaching lethal values" for spawning fish, the report said. The warm water is already taking its toll on the energy levels of the fish, thereby interfering with migration and reproduction.
The Fraser River fishery, accounting for 60 per cent of commercial fish revenue in British Columbia, was closed for the first time ever last summer after only three million of an expected 8.2 million salmon made the run.
Auditor-General Denis Desautels warned in his report last month that the Fraser fishery may have to be shut down to ensure its long-term survival. He cited global warming as one of the factors pushing the fishery to the brink.
"It's not just the Fraser, it's the entire West Coast salmon stocks that are in jeopardy. The implications are huge," said Dan Edwards, executive director of the West Coast Sustainability Association. He said conservation efforts to rebuild the salmon runs could be wasted if climate change dooms the fishery anyway. Thousands of British Columbians rely on the salmon runs for their livelihood.
The impact report also highlighted dozens of other repercussions of climate change. The Arctic has seen the most dramatic effects so far: the report says sea ice is thinning in northern regions -- changing animal hunting patterns -- while mountain glaciers are receding and Prairie grassland is creeping northward. Sea levels are also beginning to rise in the Fraser Delta and Atlantic Canada, it adds.
"We can now see direct, concrete evidence of the unacceptable ecological and economic costs of inaction on climate change," said Jim Fulton, executive director of the David Suzuki Foundation.