Invasive milfoil will thrive in Okanagan lakes impacted by climate change – February 24, 2020

With increasing global temperatures and the expectation that the Okanagan will face more droughts and floods, one nasty invader will thrive in an environment created by climate change.

Eurasian milfoil has made a home for itself in Okanagan lakes since the 1970s. Every year, the Okanagan Basin Water Board spends between $800,000 to $850,000 to remove the plant using large water rototillers that pull the plants from the lake bottoms.

There will be more milfoil as floods bring nutrients to the lakes and droughts allow the plant to grow under the direct sunlight, said water board operations manager James Littley.

Milfoil creates a number of problems for Okanagan residents, including creating a hazard for swimmers and boats, and it impacts water quality, he said.

“Once it begins to decompose at the bottom of the lake, it robs the lake of oxygen which increases algae blooms and toxic algae blooms in some cases. There have been cases in the States where fish have died in thick milfoil beds because there’s such a lack of oxygen that fish swim into it and suffocate,” he said.

An Okanagan climate change report was recently presented to regional districts around the Okanagan Valley. Amongst the report’s main conclusions is a prediction of longer warm seasons and shorter cold seasons.

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