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Metro aiding Capilano river's fish

Trucking fish reduces dam death factor

METRO Vancouver says it's making headway in its efforts to save the Capilano River's steelhead.

For several years now, the regional authority has been working to restore the dwindling trout species, whose numbers were decimated along the south coast by dam construction and other factors. And while the stock's numbers are still extremely low, Metro staff believe they are making gradual progress in the right direction.

"I don't think it's the final solution, but it helps," said Derek Bonin, planning forester with Metro Vancouver, shortly after a media event at the river Tuesday.

The Capilano's Cleveland Dam, built in 1954, blocked the natural migration of fish heading upstream to spawn. Fisheries and Oceans Canada built the Capilano Fish Hatchery as a way to help rebuild the river's populations - particularly of salmon species - and for many years now Metro, together with other agencies, has been trucking adult coho and steelhead upriver past the barrier to allow them to reproduce.

But until recently, little has been done to help their offspring to get back downstream to the ocean. Many, plunging over the dam's 90-metre spillway, have been killed by the fall onto the rocks at the bottom. Some researchers put the mortality rate as high as 90 per cent.

In 2007, spurred by a report from the Outdoor Recreation Council that dubbed the Capilano B.C.'s second-most endangered river, the region and its partners launched a project to capture juvenile steelhead and coho above the dam and haul them in tanker trucks around the death drop to the safer waters below. In 2009, workers broke up the large rocks at the base of the dam in an effort to give those that evaded capture a softer landing.

The effort has had mixed results, however. Steelhead have proven frustratingly adept at dodging the traps set out for them in the reservoir and upper river, meaning that while as many as 40,000 juvenile Coho - or about 40 per cent of the estimated population - are captured and trucked to safety these days, only about 400 stealhead - probably below the 20 per cent mark - are caught. Of those, something on the order of 10 return as adults in the summer run, and only a few more in the winter.

"The steelhead numbers are quite low," said Bonin. "They're much more evasive." But there's reason to hope, he said.

By expanding the number of traps, technicians are starting to scoop up more fish. And a tentative plan to redesign them and perhaps move some to the centre of the reservoir - where researchers believe steelhead spend more of their time - could boost the capture rate. What's more, if a long-range plan by the region to install generators on the dam comes to fruition, it may offer an opportunity to install a kind of fish filter at the plant's intake, which would help the region scoop up an even larger proportion of the fish.

"We're making some gains," said Bonin. "(But) we're trying to take . . . a cost-effective approach."

jweldon@nsnews.com

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