Photo: The Canadian Press

Parks Canada says it is responding to a suspected case of whirling disease in Yoho National Park, in British Columbia's southeast Rocky Mountains. In order to prevent further spread to other waterbodies, Emerald Lake, Emerald River, Peaceful Pond and One Duck Lake, it's shorelines and tributaries are all closed. Emerald Lake in Yoho National Park is seen on a calm day in this Oct. 22, 2009 photo. THE CANADIAN PRESS/Bill Graveland

Parks Canada says it is investigating a suspected case of whirling disease in Yoho National Park, in British Columbia’s southeast Rocky Mountains.

A statement from Parks Canada says it’s the first time the parasite that causes the disease has been detected in the province.

It says young fish, such as rainbow and brook trout, are especially susceptible to whirling disease, with a mortality rate of about 90 per cent.

The statement says once established it’s nearly impossible to eradicate the parasite, which is a known aquatic invasive species.

In order to prevent further spread to other waterbodies, Emerald Lake, Emerald River, Peaceful Pond and One Duck Lake, along with their shorelines and tributaries, have been closed. The statement says all watercraft, water-related gear and angling are prohibited in those waters with fines for violations reaching up to $25,000.