Scientists examine brown trout population in Calgary

Fewer eggs have been found since the 2013 flood

Image | brown trout

Caption: Two teams of rafters searching for brown trout eggs on the Elbow River in Calgary.

Scientists, students and volunteers are on the hunt for declining numbers of brown-trout eggs — also known as redds — in the Elbow River.
The egg search is an annual affair, but the count was down last year because of the 2013 flood.
"Brown trout are similar to salmon in that the female excavate a small nest in the bed of the river when they lay their eggs and you can actually see those," said fisheries biologist Chris Bjornson.
The survey is important because a healthy brown trout population means a healthy river, he said.
In 1980, the first year of the egg hunt, the number of redds peaked at 427. Last year the group only found 101 nests.
"Direct result of the 2013 flood," said Bjornson. "Where they spawn is in the gravel substrate's, and the gravel gets moved by the big floods."
Even though fewer redds were found last year, Bjornson says the brown trout population is strong in Calgary.