Alberta Environment is working to figure out if tributaries of the Bow River are infected with whirling disease.

The discovery was made in November in the Bow River right where it meets the Highwood River.

Because the Highwood is a breeding area for trout and whitefish, and the disease usually only affects fry and fingerlings, Peter Giamberardino with Alberta Environment and Parks says it's too early to tell if the disease has spread to the Highwood or Sheep Rivers.

"We've done sampling throughout the Province where wild trout are. And we're still trying to determine where the disease exists. So, we're still in that stage at the moment."

Whirling disease is not a threat to people or pets and is a cause of death in the younger life stages of susceptible freshwater finfish. Overall deaths of infected fry and fingerlings can reach 90 percent.

Affected finfish may exhibit any of the following signs:

Behaviour:
-whirling swimming pattern

Appearance:

-skeletal deformities of the body or head, for example, shortening of the mandible and indentations on the top of the head
-tail may appear dark or even black

For more information on Whirling Disease click "HERE."