Thousands of fish die from “winterkill” in Vermilion Lakes near Banff

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Hundreds of fish have died or are dying within the Vermilion Lakes close to Banff on account of a phenomenon often known as “winterkill.”

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Final weekend, Parks Canada officers had been contacted by somebody involved in regards to the variety of lifeless fish on the floor or underneath the ice on the lakes – significantly the second Vermilion Lake. The lifeless white suckers and brook trout might be seen within the few open areas of the frozen lakes and are seen from the shorelines.

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The Parks Canada workforce took oxygen measurements underneath the ice and decided there have been very low oxygen ranges, mentioned Mark Taylor, aquatic ecologist workforce chief in Banff Nationwide Park.

“It is a identified and understood phenomenon on the planet of fisheries administration referred to as winterkill,” Taylor mentioned.

When a chilly snap causes an additional thick layer of ice and the ice is roofed with snow, daylight cannot attain the water and the vegetation and algae within the water cease producing oxygen, Taylor defined. In consequence, the oxygen degree within the water drops.

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“That is 1000’s, if not tens of 1000’s of lifeless fish. Most of them are underneath the ice and you’ll’t see them,” Taylor mentioned.

This mass kill of fish just isn’t a priority for the long-term well being of fish populations within the park, he mentioned throughout an interview on Thursday. The fish will decompose and launch vitamins again into the ecosystem that can gas the expansion of vegetation and fish subsequent yr.

“There shall be a short lived lower within the abundance of fish, however the species we discovered there are fairly widespread within the area. And there shall be elements of the lakes the place there are survivors,” Taylor mentioned. “It is a pure course of.”

At this level, the Parks Canada workforce just isn’t involved in regards to the attraction the rotting fish may have for predators, though guests ought to all the time be cautious. It’s nonetheless thought of low danger, however they are going to proceed to watch it, particularly if there’s a windy or heat climate that would carry extra predators to the area.

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“We simply need the general public to remember that we perceive what occurred,” Taylor mentioned, including that winterkill has occurred a minimum of two different instances at these lakes.

“Now we have data of what occurred in 1959 and 1964, and I really feel snug saying that it has occurred since then as properly. It’s potential that this occurred and went unnoticed.”

When fish die, they grow to be waterlogged and sink to the underside of the lakes, which may imply that the fish sank earlier than any guests to the park observed or those that noticed the fish by no means reported it to Parks Canada.

sbabych@postmedia.com