British Columbia

Lakes in Kootenay and Yoho National Parks closed after suspected whirling disease

All bodies of water in Kootenay and Yoho National Parks have been closed for the next five months after a suspected case of whirling disease was reported in British Columbia's southeast Rocky Mountains.

1st time microscopic parasite causing fatal disease in fish has been detected in B.C.: Parks Canada

A canoe on a lake with mountains in the background.
A canoeist paddles across Emerald Lake in Yoho National Park. Parks Canada says it is closing the lake, as well as Peaceful Pond, Lone Duck Pond and the Emerald River's shorelines, water bodies and tributaries until March 2024. (Bill Graveland/The Canadian Press)

All bodies of water in Kootenay and Yoho National Parks have been closed for the next five months after a suspected case of whirling disease was reported in British Columbia's southeast Rocky Mountains.

Parks Canada says in a news release it's the first time the microscopic parasite that causes the fatal disease in fish has been detected in the province.

The agency says it is closing Emerald Lake, Peaceful Pond, Lone Duck Pond and the Emerald River's shorelines, water bodies and tributaries until March 31, 2024, to limit further spread.

It said in an earlier statement that once established it's nearly impossible to eradicate the parasite, which is a known aquatic invasive species.

Parks Canada says officials are conducting further sampling on the Kicking Horse and Kootenay rivers, but preliminary test results found suspected cases of whirling disease in the Kicking Horse River, Wapta Lake, Finn Creek, Monarch Creek and the confluence of Emerald River and the Kicking Horse River.

rainbow trout which is displaying deformities indicating whirling disease
This rainbow trout displays the characteristic black tail and skeletal deformities indicative of whirling disease. (Stephen Atkinson/Oregon State University)

The Canadian Food Inspection Agency says on its website that whirling disease impacts various species of trout and salmon as well as mountain whitefish, is particularly deadly for younger fish and can also cause skeletal deformities.

Though the CFIA says the disease does not pose a risk to human health, people can accidentally spread it.