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Whirling disease threatens fish in Kootenays

CKISS urges anglers to prevent introduction whirling disease in Central Kootenay
In fish, the parasite affects the cartilage near the spine, leading to skeletal deformities of the spine or skull. This causes the fish to abnormally whirl in a tail-chasing behaviour and/or display a blackened tail. Photo courtesy S.Hallett

A microscopic parasite is threatening fish in waterbodies in the region, and further spread of the disease it causes is of prime concern.

The Central Kootenay Invasive Species Society (CKISS) is issuing a critical alert to all anglers in the region, urging vigilance to prevent the introduction of whirling disease into waterbodies across the Central Kootenay region.

“This urgent call comes in response to Parks Canada’s decision to close all bodies of water in British Columbia’s Kootenay and Yoho National Parks, with restrictions on watercraft in Alberta’s Waterton Lakes National Park until at least March next year,” a release from CKISS said. “The closures are aimed at slowing the spread of invasive species.”

Whirling disease, caused by a microscopic parasite, poses a severe threat to fish populations, particularly trout, salmon, and whitefish. The disease leads to skeletal deformities, resulting in a tail-chasing behavior that can be fatal, potentially affecting up to 90 per cent of juvenile fish.

CKISS said whirling disease can infiltrate new water bodies through multiple avenues. Infected fish or their parts, if moved between locations, can transport the microscopic parasite responsible for the disease. Similarly, contaminated equipment like fishing gear and boats can harbor the parasite or its spores if not properly cleaned before use in different waters.

Natural water flow, such as rivers or streams, may also aid in spreading the parasite downstream or to adjacent areas.

Additionally, human activities like stocking fish from infected sources or releasing aquarium pets into natural habitats can introduce the disease, as can improper disposal of infected fish carcasses.

CKISS says anglers are advised to adhere to the following guidelines:

• Never move fish or fish parts between waterbodies.

• Use designated fish-cleaning stations or dispose of fish parts in local solid waste systems.

• Before transferring any equipment between waterbodies, follow the Clean, Drain, Dry protocol.

• Don’t Let it Loose: never release any pet fish into a natural area. Rehome it or ask a local pet store to adopt the fish.

• If you suspect Whirling disease in a fish, report it immediately to the RAPP line at 1-877-952-7277.

“Prevention is our best defense against the spread of Whirling disease,” emphasizes Laurie Frankcom, CKISS’ Education Program Coordinator.

“By taking proactive measures and adhering to these guidelines, we can protect our precious water ecosystems and the diverse aquatic life they support.”

Parks Canada’s proactive measures are an extension and expansion of closures initially implemented in October, 2023, highlighting the urgency of the situation. It underscores the collective responsibility to prevent the spread of Whirling disease and other invasive species that threaten our water ecosystems.

CKISS is a non-profit society that delivers education and awareness programs, and promotes coordinated management efforts of invasive species in the Regional District of Central Kootenay and Regional District of Kootenay Boundary Area A and B.

Barry Coulter

About the Author: Barry Coulter

Barry Coulter had been Editor of the Cranbrook Townsman since 1998.
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