Parks Canada says it is monitoring an anthrax outbreak in remote areas of Wood Buffalo National Park.
The agency says staff have observed at least 59 bison carcasses in the park and the deaths are suspected to be caused by anthrax.
A lab has confirmed the presence of anthrax in three of the dead bison.
The park, the country’s largest national park, stretches from northeastern Alberta into the Northwest Territories.
Parks Canada says resource conservation staff are conducting daily flights to monitor the extent of the outbreak.
A national incident management team is assisting with the disposal of carcasses.
It says risk to the public remains low and road-accessible visitor facilities remain safe.