Monitoring gaps endanger salmon runs: study

Lack of accurate stock information leads to overfishing, scientists say

Times Colonist
DECEMBER 4, 2008

Salmon runs are collapsing because inadequate and inaccurate monitoring by the Department of Fisheries and Oceans is leading to overfishing, says a study published yesterday in the National Research Council’s Canadian Journal of Fisheries and Aquatic Science.

The research, conducted by Misty MacDuffee and Michael Price, biologists from the Raincoast Conservation Foundation, and Chris Darimont, a scientist from the University of California, looks at salmon stocks on the central and north coasts of B.C. between 1950 and 2005.

They found that salmon runs met their target escapements — the number of fish that reach the spawning grounds — only 50 per cent of the time on average. From 2000 to 2005, spawning chum, sockeye and chinook failed to meet target escapements by between 67 per cent and 85 per cent.

At the same time, the number of streams being monitored by DFO is shrinking and, by 2005, on the central and north coasts, only five per cent of salmon runs were monitored, the study says.

“When we don’t have the information on the stocks, we can’t justify fishing on them. We are going fishing without adequate information,” MacDuffee said in an interview.

“It is really startling how much information has been lost. They are managing the fishery on fewer and fewer runs,” she said.

As runs shrink, DFO sometimes stops monitoring the streams, meaning the strongest runs are being used as indicators of salmon runs, MacDuffee said.

“Importantly, the unmonitored runs tend to be small streams, which are the most ecologicallly important for bears and coastal wildlife and their declines or disappearances go unnoticed.”

However, Paul Ryall, of DFO’s resource management branch, said the study looks only at a small area and does not take into account other factors such as climate change and low marine survival.

“It makes large generalizations we need to be careful about,” he said. “It is not valid to say salmon stocks are on the brink of collapse.” DFO continues to monitor large and small river systems and, when the predicted numbers do not show up, numbers are adjusted accordingly, such as happened this year with Fraser River sockeye, Ryall said.

“It’s more important than just forecasting. It’s also managing the returns,” he said.

Also, the news in B.C. is not all bad and preliminary forecasts for Fraser River sockeye next year are for 10.5 million fish to return, Ryall said.

MacDuffee said she sympathizes with DFO, which is trying to manage with shrinking budgets, but, to save vital runs of salmon, there must be changes in fishing patterns.

“We have to move away from mixed stock fisheries — ocean fisheries — and if the stocks are strong enough, do terminal fisheries,” she said.


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Coastal wolf with a salmon in its month.
Photo by Dene Rossouw.