THEBACHA/FORT SMITH
As of July 16, a possible outbreak of anthrax had yet to be confirmed in Wood Buffalo National Park, as Parks Canada awaited results of testing from Lethbridge, Alta.

Lana Cortese, a biologist with Wood Buffalo National Park, wears a hazmat suit as she cleans up sand from a site at Pine Lake in the Alberta section of the park, where a dead bison was found in early July. - photo courtesy of Wood Buffalo National Park

However, anthrax remained a prime suspect as the number of dead bison continued to grow over last week in the massive park, which covers an area of northern Alberta and the southern NWT.

Tim Gauthier, a park spokesperson, said the results might be known by the end of last week or early this week.

There have been 49 bison carcasses discovered in the park as of July 16.

"An aerial patrol (on July 12) found 14 more carcasses at Sweetgrass Prairie," said Gauthier. "It's a remote area in the south of the park."

One other carcass was spotted on July 14 along Parson's Lake Road by a ground patrol.

"All of the animals have been found on the Alberta side of the border," said Gauthier.

An aerial patrol on July 15 found no new carcasses in areas of the park where bison are known to congregate, he added. "One day doesn't make a trend, but it's a positive sign."

While the presence of anthrax has yet to be confirmed, Gauthier said, "A number of carcasses that have been found had the appearance of animals that have died from anthrax."

That includes lying on their back or side with the legs very stiff in a sawhorse position.

Virtually all of the carcasses are in remote areas of the park and will be left to decompose naturally.

"The Parson's Lake Road one we are going to burn," said Gauthier. "That's part of our protocol. Anything that's even close to front country we will burn, and we use a high-intensity fire using coal and green wood. The theory being that the intense heat will kill the spores."

Parson's Lake Road was already closed prior to the discovery of the bison carcass because of fallen trees in the area, but Parks Canada has now added caution tapes to either side of the wilderness road.

"While we have not yet confirmed the existence of anthrax and we are waiting for our lab results to come back, we have put in place all of our protocols just to ensure that visitor safety is not compromised," said Gauthier.

Those protocols include stepped up aerial and road patrols.

Anthrax control measures near high-use areas, such as roads, involve the rapid detection and disposal of dead bison to minimize the release of anthrax spores into the soil.

On July 9, a routine patrol flight discovered the first 34 bison carcasses in several locations in the Alberta section of the park - Trident Meadows, about 35 km north of Garden River; Lake One in the central area of the park; Sweetgrass Prairie; and one deceased animal on the Salt Plains, about 15 km from the Salt Plains Lookout.

The discoveries have not affected the operation of the park.

"All park visitor facilities and services are open, and we are welcoming members of the public," said Gauthier.

In fact, he noted the park's annual Pine Lake Picnic went ahead as usual on July 12 and attracted about 350 people to the lake located about 60 km south of Fort Smith.

Anthrax, which is caused by the bacteria Bacillus anthracis, occurs naturally in the park.

Under certain conditions, spores concentrate in low-lying areas and bison contract the disease by inhaling contaminated soil while wallowing in the dust to get rid of bugs.

"It's the weather conditions," explained Gauthier when asked why the anthrax spores become active at certain periods. "It's usually a period of severe heat followed by precipitation."

Anthrax outbreaks have been observed 13 times in the park and the NWT between 1962 and 2012.

There has never been a case of visitors contracting anthrax in the park, which is home to about 5,000 bison.

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