WALES, Mass. (AP) — State wildlife experts say a massive fish die-off in a Wales lake was caused by last week's excessive heat.

The state Division of Fisheries and Wildlife has determined that the fish kill at Lake George was caused by hot temperatures that caused oxygen levels to deplete.

Hundreds of white perch died in the lake last week.

Board of Health Chairwoman Susan Cadieux tells The Republican she was told that white perch were susceptible to the warm water temperatures because they are at the end of their breeding season, which makes them "extremely delicate."

She says the lake's temperature was almost 87 degrees on Monday.

The fish die-off has nothing to do with recent treatment of the lake for nuisance vegetation.

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