British Columbia

Kootenay Lake fishery in peril, B.C. Wildlife Federation says

Biologist warns the Kootenay Lake ecosystem is 'òut of balance' and requires agressive provincial intervention to save freshwater salmon and an important sport fishery.

Iconic kokanee salmon populations are swinging wildly as lake trout predators boom

Biologist warns the Kootenay Lake ecosystem is 'out of balance' and requires agressive provincial intervention to save freshwater salmon and an important sports fishery. (Steve Hossack/CBC)

The B.C. Wildlife Federation is warning Kootenay Lake's ecosystem is "out of balance," and is calling for aggressive provincial action to revive iconic kokanee salmon stocks.

"I've been working on this lake for almost 50 years, and I've never seen anything like this," Harvey Andrusak, biologist and past president of the B.C. Wildlife Federation, told CBC Daybreak South host Chris Walker.

"The public has to wake up to the fact the government isn't doing its job."

Andrusak, who once worked as the southeast B.C. director of fisheries within the provincial Ministry of Environment, says Kootenay Lake once teemed with kokanee — over a million spawning fish a year — but just around 10,000 remain.

A ministry update published in January shows estimated kokanee populations swinging sharply over the last decade, from 1.25 million in 2012, to a low of 12,000 in 2019, to 90,000 in 2020.

Andrusak says it is proof the Kootenay Lake ecosystem is out of balance.

"Essentially, the predators, which is the rainbow and bull trout, have eaten out all the kokanee. That's the simple explanation," he said.

"The predators outpace the kokanee in numbers."

Root cause of kokanee collapse unclear

It is a problem that has confounded kokanee populations throughout the Pacific Northwest.

Kokanee, a subspecies of sockeye salmon, do not migrate to the sea but instead live out their entire lives in freshwater lakes and rivers.

Over the last decades, the fish have thrived in some lakes, crashed in others.

The root cause of exploding lake trout populations and declining Kokanee stock remains a matter of scientific debate, but research has pointed to factors such as pollution, lake levels, habitat loss, and climate change as risk factors in some areas. 

Andrusak says, regardless of the cause, the B.C. government has a responsibility to act.

"We've known about this problem for almost 10 years ... 10 years later we haven't moved the needle at all in terms of increasing the number of kokanee.  And the government's inaction on this is just unacceptable," he said.

Andrusak points to programs in other jurisdictions, like Idaho, which stabilized populations through massive kokanee egg planting and aggressive trout reductions. 

"By doing so, within six years they had recovered the lake," he said.

Province defends management strategy

The B.C. Ministry of Forests, Lands, Natural Resource Operations and Rural Development, which is responsible for kokanee management, points to a number of efforts to recover stocks, including a new Angler Incentive Program to boost lake trout harvest.

"It was very successful ... with over 11,000 fish entered in the program, and an overall increase in total harvest of 60-85% from the previous year," the ministry said in a written statement to CBC News.

"We will continue to work with the [B.C. Wildlife Federation], local First Nations and other partners to improve the performance of actions to recover kokanee." 

In 2016, the ministry planted more than half a million kokanee eggs in Kootenay Lake spawning channels and reported a 90 per cent hatch rate. 

The government says recovery will take time. 

Andrusak argues its too little, too late:  sport anglers are now fishing elsewhere because the imbalance has led to a shortage of trophy trout as well. 

"As a result of so few kokanee being available, the rainbow and bull trout have substantially decreased in size and condition to the point where anglers are discouraged from fishing on the lake."

Kootenay Lake is a destination for anglers seeking to hook prized "Giants of the Gerrard"  rainbow trout.

The ministry admits participation in its program is down from last year and is encouraging local fishers to cast their lines.

Provincial biologists will conduct a new count of the kokanee population at gates along the Meadow Creek spawning channel at the north end of the Kootenay Lake within the next four weeks.

With files from CBC's Daybreak South