Perched on edge of success
Five years after waging a war against invasive fish in the region’s lakes and waterways, the fight appears to be over.
The results are good news for the native species that call the area home.
Officials with the Ministry of Forests, Lands and Natural Resource Operations are claiming victory over the invasive fish, particularly the yellow perch and small-mouth bass.
Andrew Klassen, a small-lakes biologist with the ministry, said there is no sign of the fish in any of the nine lakes identified for a special treatment.
“As far as we know, we’ve gotten rid of all of them from the whole Thompson drainage,” he told KTW.
The nine lakes treated include Skmana, Little Skmana, Nellie, Forest, Gardom, Phillips, Fleming, Skimikin and Miller.
The five-year program began after fears perch would eventually ravage the Thompson River basin, destroying the popular salmon runs.
Not only are the perch gone from the lakes, but other amphibians and invertebrate that were ravaged by the fish have returned in droves.
Klassen noted one example at Gardom Lake.
In 2009, he could only find one tree frog at the lake but, when he returned this year, there were hundreds.
“It’s like night and day,” Klassen said.
A favourite of fisherman on the East Coast, perch are a prodigious fish that can lay up to 30,000 eggs per female and easily take over a water system.
The perch likely made their way from the Columbia and Kootenay basins, then were dumped illegally into local lakes by a bucket brigade — anglers intent on creating an Eastern fishery.
In 2008, KTW caught up with a crew on Forest Lake, armed with rotenone, a natural organic chemical derived from a bean plant, to destroy perch in the lake.
The chemical, in low concentration, is considered an effective means of killing the fish without harming other animals or humans.
It took nearly four months of prep work, mostly to pump the lake down three feet and $200,000 in funding to carry out the project.
The majority of funding for the entire $1.3-million effort came from the Habitat Conservation Trust Foundation, money that comes from hunting- and fishing-licence sale revenue.
But, the work is not completely done.
To ensure the unwanted fish don’t return, the ministry has applied to the same foundation for another $100,000 over another three-year period to follow up and assess connecting creeks in the drainage.
In the meantime, ministry officials continue to keep a close eye on Stump Lake — more specifically, the pH level in the lake.
Since 2006, ministry biologists have been trying to save fish stocks, with lukewarm results.
In 2006, the MOE began a plan to restock the lake, located 40 kilometres south of Kamloops, by introducing 225,000 rainbow trout and kokanee.
Klassen noted the trout fishery is doing better than previous years, in part to the high water levels this year.
A pH level above 9.1 makes it difficult to keep fish alive.
The current pH level in Stump Lake is 9.1.