Bison move down Highway 5 in Wood Buffalo National Park. Parks Canada has confirmed an outbreak of anthrax among bison that live in the park. - NNSL file photo |
Anthrax outbreak confirmed in National Park
Total of dead bison hits 52, but officials hope the worst is over
Paul Bickford
Northern News Services
Monday, July 27, 2015
THEBACHA/FORT SMITH
An anthrax outbreak has been confirmed in Wood Buffalo National Park.
Testing at a laboratory in Alberta has discovered the presence of anthrax in one sample from bison carcasses discovered in the park since July 9.
"One of our tests on a bison on Parson's Lake Road came back as a positive," said Mike Keizer, the park's manager of external relations.
At least three carcasses were tested, but two came back negative.
"You rarely get a false positive, but you can get false negatives," said Keizer.
The one positive result has been enough to confirm the presence of anthrax, especially considering the number of dead bison.
As of July 23, there have been 52 carcasses spotted in the park - virtually all in remote areas.
"Bison don't die en masse historically, except for anthrax," said Keizer.
Many of the carcasses
had the appearance of animals that died from the disease.
That included lying on their back or side with the legs very stiff in a sawhorse position.
"The physical indications are there," said Keizer.
"And, of course, we've got the one positive now that proves anthrax is here."
As of July 23, no new carcasses had been spotted in the park for almost a week, leading to some optimism that the worst of the outbreak may be over.
"We're not calling it yet, but we're hoping for a short-lived one in the context of the duration of the outbreak," said Keizer. "But that could change with the next survey flight. At this point, we've had a couple of survey flights and nothing new has been found."
The recent cool weather is seen as a positive development based on the pattern of anthrax cases that have happened in the past.
"Usually, we have a really wet period followed by a really hot, dry period, and that's sort of been the norm," Keizer explained.
"Then you see anthrax coming up in the hot dry period and then it tends to slow down when it gets cool again."
All the park's anthrax protocols remain in place, including advice for people to stay away from bison carcasses if they happen to see one and to inform the park office immediately if this should happen.
"We have not closed any areas of the park, said Keizer.
"But those who we know are going backcountry we sit down and talk to them about anthrax," said Keizer.
The protocols also include stepped up aerial and road patrols.
The bison carcass on Parson's Lake Road was being burned as of late last week.
The carcasses in remote areas of the park, on the other hand, will be left to decompose naturally.
All were found in the Alberta section of the massive park, which includes a section of the southern NWT.
Two carcasses were found at the Salt Plains, but far away from the lookout area.
Anthrax, which is caused by the bacteria Bacillus anthracis, occurs naturally in the park, which is home to approximately 5,000 bison.
Under certain conditions, spores concentrate in low-lying areas and bison contract the disease by inhaling contaminated soil as they wallow in the dust to get rid of bugs.
There have been 13 recorded anthrax outbreaks in the park and the NWT between 1962 and 2012.
There has never been a case of visitors contracting anthrax in the park.
