The vulnerable waters and freshwater fisheries of British ColumbiaB次元官网网址檚 lakes and rivers are under threat from whirling disease. 

Three trout samples taken from the southern arm of Kootenay Lake have tested positive for the condition. Whirling disease is caused by a parasite, Myxobolus cerebralis, that attacks the brain stem, spinal cord, and nervous tissue of juvenile salmonid fish. The disease causes an erratic "whirling" swimming pattern, deformities of the spine and jaw, and dark patches on the skin near the tail. It is not a health risk for humans or pets.

When infected fish die, spores carrying the parasite spread into the water and seek out aquatic worms (hosts) to repeat the cycle. There is no treatment for whirling disease, so containment and prevention are the best course of action. 

It is unknown if there is any relation to detections in Yoho National Park, the site of the first confirmed case of whirling disease in B.C. in September 2023.

In partnership with First Nations, the Canadian Food and Inspections Agency (CFIA), and Parks Canada, the province began enhanced monitoring for whirling disease earlier this year. Provincial biologists are still processing additional samples from the 2024 season.

In response to these detections, the province plans to continue enforcing the new "Pull the Plug" protocol. As of May 17, 2024, it is illegal to transport watercraft with the drain plug still in place. Before transporting a boat or other watercraft, operators must drain all water on dry land, including all internal compartments such as ballasts, bilges, and live wells.

In response to the news of these confirmed cases, the B.C. Wildlife Federation (BCWF) expressed the new for additional federal funding for defence against invasive threats. 

B次元官网网址淲e are disappointed that the presence of whirling disease on B.C.B次元官网网址檚 eastern border discovered late last year did not merit a stronger response from the federal government,B次元官网网址� said Jesse Zeman, BCWF executive director. B次元官网网址淎 defence program for whirling disease can do double duty in preventing the spread of the parasite and invasive mussels. The federal government needs to step up with funding to protect British Columbia waters.B次元官网网址�

The new "Pull the Plug" law falls under the "Clean, Drain, Dry" decontamination program for all boats and water equipment to help prevent the spread of whirling disease, along with never moving fish or fish parts from one water body to another.

B次元官网网址淎t this point no watercraft should be able to enter B.C. without confirming that it is free of invasive plants and animals, especially the parasite that causes whirling disease and invasive quagga and zebra mussels,B次元官网网址� said Zeman. B次元官网网址淏oaters must ensure that they clean, drain, and dry their watercraft and trailers, and make sure equipment such as fishing gear, buckets, and coolers are free of invasive creatures."

Kootenay Lake is one of the largest freshwater fisheries in B.C. and supports populations of Gerrard rainbow trout and kokanee salmon, attracting anglers from across North America.

B次元官网网址淚t is not clear how the parasite will affect Kootenay LakeB次元官网网址檚 kokanee and trout fisheries, but the spread of this parasite shows the vulnerability of our lakes and rivers to outside threats,B次元官网网址� said Zeman.

For more information on whirling disease and prevention, visit .