Parks Canada has restricted fishing in Cuthead Creek in Banff National Park to protect cutthroat trout from whirling disease.

It is also restricting boating and swimming in the creek — although people will be allowed to wade across it on official trails if there is no bridge.

"Lab results have confirmed presence of whirling disease in Banff National Park," said Parks Canada in a statement.

"This parasitic disease affects some fish species but does not present any health risks for people or other mammals."

Parks says the westslope cutthroat trout is a threatened species, so they are trying to protect its habitat from the whirling disease parasite.

Violators could be charged under the Canada National Parks Act, which has a maximum penalty of $25,000.

More information can be found on the Parks Canada website.