Originally Published by Global News, July 27, 2015

Watch above: Westslope cutthroat trout used to thrive from Banff National Park all the way down the Bow and Oldman Rivers, but now an invasive species is threatening the freshwater fish. It has prompted Parks Canada to take recovery efforts to new heights. Sarah Offin explains.

BANFF, Alta. – Fish were never meant to fly, but the once simple existence of westslope cutthroat trout has become somewhat complicated, and caused Parks Canada to take action.

“In certain water bodies they’ve been entirely eliminated. Those are areas closer to the Bow Valley and human settlement, but also where a lot of the stocking was done. That’s what sort of caused the problem, going back as far as 100 years ago,” said Mark Taylor, an aquatic ecologist with Parks Canada.

Cutthroat trout are a threatened species. Populations in Banff National Park have been driven out by rainbow trout, which were introduced as a favored fish for anglers over a century ago. Cutthroats breed with the rainbows, creating a hybrid species.

There are 10 lakes in Banff National Park that still host pure populations of the fish. Sawback Lake, located about 25 kilometres into the back country northwest of Banff, is one of them. Sawback is where Parks Canada has flown about a dozen lucky volunteers with Trout Unlimited. The fishermen and women are tasked with catching 100 cutthroat trout.

“The fishing is just the icing on the cake actually,” said volunteer Gerry Stephenson. “I’m 83, so my days for hiking into places like this – that was a while ago.”

The youngest recruit, 13-year-old Charlie Buffler, carries the coveted distinction among the volunteers of having caught the most fish.

“Is there a secret to catching them?” I asked.


“What is it?”

Charlie stayed silent.

“You’re not telling?”

“Nope,” he grinned.

Across the valley lies Rainbow Lake, a body of water that earned its name from the invasive fish that thrived there. But those trout, all 528 of them, have been removed from the lake by Parks Canada over the last four years.

Taylor is now working to rename the lake after the cutthroat trout caught at Sawback were flown by helicopter and released into their new home.

“The lake is glass calm, and as soon as we put the first cutthroat in the lake there was fish rising and jumping already,” said Bill Hunt, resource conservation manager with Parks Canada. “So there’s a ton of food in this lake and the fish are happy to be here.”

The hope is that the newly-released fish will reproduce, creating a new gene pool that will then travel to water bodies downstream.

The recovery project cost Parks Canada $160,000.

Photo courtesy of Sarah Offin / Global News.