Tens of thousands of fish that washed up on the north shore of Lake Erie over the Labour Day weekend died of natural causes related to lack of oxygen in the water, early test results reveal.
The environment ministry said Friday the water tests confirm that a naturally occurring temperature inversion brought an oxygen-depleted layer of water from the bottom of the lake close to the surface causing the widespread kill.
“Samples back from the lab do not show any evidence of a manure spills or anything unusual in terms of contamination. The information that we have suggests the fish may have been killed as the result of natural causes,” said ministry spokesperson Kate Jordan told the Star.
Jordan said further data confirmed a sudden temperature drop in the lake and near-zero oxygen in the water below 12 metres. Test results on the fish are expected next week.
Meanwhile, the rotting fish carcasses as well as some dead birds continue to line the shore of Lake Erie for 40 kilometres.