EGAN: Why are the great sturgeon of the Ottawa River dying?

By Kelly Egan, Ottawa Sun, August 29, 2020

On the weekend of Aug. 23, a large fish washed up dead on the sandy shores of Constance Bay, overturned on its thin white belly, strange little whiskers pointing to the sky.

It was a sturgeon — more properly a lake sturgeon — about four feet long and likely weighing in excess of 30 pounds. Neighbours, beach-walkers, began to chatter. Not only was it a rare sight, but it also wasn’t the first one this summer.

(...)The City of Ottawa, it turns out, carefully tracks the temperature of the river at its two drinking-water intakes. (The precise reading actually affects the water treatment process.)

In July, the average temperature of the river at Britannia was 24.9 C, a full 1.5 degrees higher than the 10-year average of 23.4. August was higher as well, with average readings so far this month of 24.6 C, versus the historic average of 23.6 C.

And something else: In three of the past 12 years, the temperature of the river never rose above 25 C. Not for one day. This year, it has exceeded 25 C on 26 days, the highest number since at least 2009.

https://ottawasun.com/news/local-news/egan-is-something-killing-the-great-sturgeon-of-the-ottawa-river/wcm/3a74b1ad-90d7-4a11-b560-34bee217b1a9/