Invasive snails washing up in droves on the shore of Bass Lake should not be cause for alarm, says local naturalist Bob Bowles.
A Facebook post with pictures of the snails at Bass Lake has been shared hundreds of times, leading some to worry about the effect the gastropods might have on humans.
Bowles determined the little creatures to be banded mystery snails (Viviparus georgianus). That was also the verdict from EDDMapS, the Early Detection and Distribution Mapping System, to which the person who posted on Facebook sent photos for confirmation.
“They’re all through the Kawarthas and I’ve seen them here in Lake Couchiching and Lake Simcoe,” Bowles said.
He noted the snails “can carry a pathogen that can affect fish and aquatic life,” but he doesn’t believe they can cause swimmer’s itch in humans, contrary to the beliefs of some.
“We do get swimmer’s itch in some lakes around here, but there’s very little danger of getting anything in Bass Lake from these snails being there,” he said. “If they did (cause swimmer’s itch), it would have manifested itself by now because there are so many there.”
Bowles often offers his expertise to a Kawartha Lakes cottagers’ association, and no one there has brought up swimmer’s itch as a concern.
“(The banded mystery snails) are thick up there, but no one’s ever mentioned swimmer’s itch,” he said.
He pointed to the recent extreme heat as a probable reason for so many snails on the shore and in the water at Bass Lake.
“With Bass Lake being a smaller lake, they just did well. There was more reproduction,” he said.
