Reason for mass die-off of fish on Lake Winnipeg remains a mystery: province

WINNIPEG -- The Manitoba government said they’re unable to determine why hundreds of dead fish washed up on the shores of Lake Winnipeg last month.

Hundreds of dead carp could be seen washing up on the shores of Lake Winnipeg in June, prompting the province’s wildlife and fisheries branch to conduct tests on the tissue of the fish to determine if a virus caused the mass die-off.

The province was looking to see if it was caused by the Koi Herpes virus, which has been found in Manitoba before, or the Spring Viraemia of Carp virus, which affects different species of carp.

A spokesperson for the province said they did not find evidence of either virus with the tests.

“Based on the evidence collected to date, Manitoba Agriculture and Resource Development (ARD) is unable to determine what caused this die-off,” the spokesperson wrote in an email to CTV News. “At this time there will be no further investigation.”

The province said if residents start noticing large numbers of dying or freshly dead fish, they’re asked to notify the wildlife and fisheries branch as soon as possible by phone at 204-793-1154 or by emailing [e-mail].

- With files from CTV’s Danton Unger.