BANGOR, Maine (AP) — The Maine Department of Inland Fisheries and Wildlife says there’s no cause for alarm by reports of dead fish in four northern lakes.

A large number of fish, mostly yellow perch, have died on Long Lake, Cross Lake, Square Lake and Madawaska Lake, Frank Frost, the department’s fisheries resource supervisor for the Fish River Lakes Region, told the Bangor Daily News.

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Such fish kills are often caused by temperature stress, said David Russell, a state fish pathologist.

Russell said the fact that fish are dying needn’t cause alarm, and he noted in a blog post that thousands of dead white and yellow perch can be observed each year in some part of the state.

“Numbers and frequency of events are exacerbated by temperature fluctuation and by very warm temperatures,” Frost said.

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