An anthrax outbreak caused by dry weather has taken its toll on northern bison herds.
For the first time, bison have died at Syncrude Canada’s Beaver Creek Wood Bison herd in northern Alberta.
Four bison from the Beaver Creek Wood Bison herd have died, three were infected and confirmed positive with anthrax. Results are not official on how the fourth bison died, said Leithan Slade, spokesperson for Syncrude Canada in Fort McMurray.
There are more than 300 animals in the herd and Syncrude officials are working to protect workers and the remaining animals.
The first animal was discovered Aug. 12 and the other animals over the next weeks.
Anthrax is a reportable disease in Canada and is naturally occurring in soils.
An animal that dies of anthrax sheds the anthrax bacterium. Livestock are most commonly infected by ingesting the spores from contaminated pastures, while grazing, especially in dry weather when grass is short.
Further north in Wood Buffalo National Park, 60 bison have died from anthrax this season. The last two carcasses were discovered near Sweetgrass in the south central part of the park Aug. 25 during an aerial patrol of the area. Those carcasses appeared old, said Tim Gauthier with Parks Canada.
No fresh carcasses have been found in the last 21 days, leading staff to believe the outbreak is over, he said.
“The outbreak is confined to six small areas of the park, all of which have had anthrax before.”
On average about 60 bison die each year from anthrax in Wood Buffalo National Park.
There are about 3,500 bison in the Wood Buffalo herd. The outbreak does not threaten the long-term viability of the herd, he said.