Whirling disease in Oldman watershed, CFIA

The Canadian Food Inspection Agency (CFIA) has declared the Oldman River watershed infected with whirling disease.

The declaration covers all streams, creeks, lakes and rivers feeding into the Oldman River, including those in Waterton Lakes National Park. The affected zone ends at the confluence of the Oldman River and South Saskatchewan River.

Areas in Alberta outside the Bow River and Oldman River watersheds were previously declared as a buffer area and are not affected by today’s declaration.

Whirling disease action plan

The CFIA’s announcement follows a declaration of infection in the Bow River watershed in February. New detections of whirling disease from ongoing sampling and testing should not be taken as evidence the disease is spreading.

The province is continuing to stress the importance of steps to prevent the spread of whirling disease and aquatic invasive species. All motorized boats should have drain plugs pulled while in transportation. Bait fish should not be released.

About Whirling Disease (Myxobolus cerebralis)

Whirling disease is caused by Myxobolus cerebralis, a microscopic parasite of salmonid fish, including trout, salmon and whitefish. The organism possesses a complex lifecycle that requires a salmonid fish and an aquatic-worm, Tubifex tubifex, as hosts.

Species such as rainbow trout, cutthroat trout and whitefish are particularly susceptible to whirling disease, though impacts of the disease differ among salmonid fish species and in different waterbodies.

The severity of whirling disease depends largely on the age and size of the salmonid host. Young fish are most vulnerable, with mortality rates reaching up to 90 per cent.

If you suspect a case of whirling disease, call 1-855-336-BOAT (2628).

Agencies/Canadajournal