With helicopters, explosives, engineering, Canada races to save Fraser salmon
Facing swift currents, rising water levels and temperatures that could reach 37 Celcius (98.6 degrees Farenheight), dozens of Canadian engineers, biologists and technicians will spend the coming days moving boulders, scaling cliffs and transporting fish by helicopter in order to save salmon blocked by a landslide.
The task for the emergency responders assembled near a remote stretch of British Columbia's Fraser River? Either clear enough boulders to remove the 15-foot waterfall so that migrating salmon can naturally head upstream or find another way to get them there.
Jonathan Wilkinson, Canada's minister of fisheries, oceans and the Coast Guard, told reporters on Aug. 6 that workers at the landside site near Big Bar in the province's north have installed a fish wheel to gather up salmon that can't move ahead. The fish are then radio-tagged and moved into "secure buckets" where one of two helicopters takes them on a short trip north, he said.
“As of yesterday, 5,000 fish had been moved this way. This is important to ensure that some fish are getting through the blockage although the number of fish that can be moved this way is obviously limited,” he said on Aug. 6.
Some 90,000 sockeye and other salmon species headed to their spawning grounds have reached the blockage to date. But a more pressing concern for the rescue effort is what happens over the coming weeks when an estimated two million sockeye alone are expected to arrive.
“We are certainly operating with a very strict timeline," the minister said. "It is imperative that we do whatever we can to enable as many fish as possible to pass through the slide to secure the sustainability of these runs and obviously the communities that run on the health of these stocks.”
The Fraser River, which also runs into the US state of Washington, is an important source of salmon for social, ceremonial and sustenance for First Nations as well as for commercial and recreational fishing. Fraser River runs have been limited in recent years -- last year the run included 10.7 million sockeye -- but the 2019 preseason sockeye estimate was around 4m, according to Grand Chief Edward John, a hereditary chief of the Tl'azt'en Nation.
He told reporters that those estimates have been downgraded to 2m to 2.5m sockeye according to the results of recent test fishing.
“Nonetheless, if it’s 2m fish that are going to be at the slide area, how are these fish going to be assisted to move above the slide area?” he said.
Wilkinson said that in addition to the helicopter efforts -- the installation of a fish ladder is also being considered -- the joint response from the federal government, the British Columbia government and First Nations involves 16 engineers on the ground moving boulders to try to create a natural path for the salmon. That exercise that preceded weeks of careful “scaling” work on surrounding cliffs to ensure the safety of workers, he said.
Additionally, responders have transported around 175 fish of the Early Stewart sockeye run that have reached the blockade to a fish health lab in the province in an effort to preserve the stock's genetic line.
Wilkinson added that the response is currently focused on what he called "rock manipulation", using jackhammers, lift bags and explosives to reposition the boulders, but officials are willing to consider other options.
One of the most popular ideas has been the use of a "salmon cannon", a technology developed by Seattle, Washington's Whooshh Innovations that uses air pressure to transport fish through a tube.
Wilkinson said that the cannon is being considered and that worker safety and engineering issues, related to the construction and placement of a platform in the water that the equipment would require, are being studied.
“We haven’t ruled the Whooshh fully off the table”, he said adding that the use of a fish ladder is more "highly probable" if the effort to move the boulders fails.
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