THEBACHA/FORT SMITH - It may just be two dead bison, but Wood Buffalo National Park is testing recently-discovered carcasses for anthrax.

In this photo from 2007, a bison carcass is burned during an anthrax outbreak in Wood Buffalo National Park. Two carcasses recently found near Highway 5 in the park were similarly burned as a precaution while testing is done to determine if the animals died from anthrax. - photo courtesy of Wood Buffalo National Park

The dead animals were discovered within a day of each other in late July on Highway 5 near Raven Tower, about 140 km northwest of Fort Smith.

"There are many other reasons a bison could die besides anthrax," said Mike Keizer, the external relations manager with the park.

The park sees dead bison every year for one reason or another, such as vehicle collisions, wolf attacks and old age, he said. "So finding one bison dead is not a big surprise for us."

However, Keizer explained samples from the two recent carcasses, which were estimated to be at least a week old, are being tested for anthrax because of an outbreak outside the park in the Slave River Lowlands and the fact the carcasses were fairly close together.

There were also no visible indications the animals had been hit by vehicles.

The test results are expected back at any time.

Keizer noted, even if the tests come back negative for anthrax, the animals still may have died from the disease.

"Sometimes they can test negative, even though they're positive," he noted, explaining a fresher carcass provides a better sample for testing.

Keizer said the recent cooler and damp weather conditions are not conducive for an anthrax outbreak.

The carcasses were discovered on either side of Highway 5. One was about a half-kilometre off the road and the other about 100 metres into the bush.

They were located by a highways crew from the GNWT's Department of Transportation, Keizer said. "I guess one was quite ripe, so they were able to smell it from the highway."

Both carcasses were burned as a precaution.

Keizer said there have been regular aerial surveys for anthrax all summer, both as part of forest fire flights and specifically to look for dead bison.

"We've been monitoring all summer for it and we haven't seen any other animals down," he said.

The last anthrax outbreak in the park was in 2007.

Keizer said anyone planning to visit Wood Buffalo National Park can do so without any worry, even if the carcasses test positive for anthrax.

According to expert medical advice obtained by the park, anthrax is very hard for humans to contract.

"You're certainly not going to get it the way the bison do, which is inhalation (of spores)," Keizer said.

The bison contract the disease from spores in the ground while wallowing in dust.

Keizer noted anthrax spores are endemic in many regions of North America.

A human would only get anthrax from a bison carcass by licking it, eating it raw or sticking a hand with open wounds into the carcass.

"Hopefully, a visitor wouldn't do that," Keizer said.

If visitors spot a bison carcass, they should leave the immediate area and report it to park officials.

Meanwhile, the anthrax outbreak in the Slave River Lowlands, about 80 km southeast of Fort Resolution, continues to draw to a close.

Two more carcasses were found in late July, bringing the toll to 45 as of Aug. 3.

Ella Stinson, a spokesperson for the Department of Environment and Natural Resources, said the recently-discovered carcasses were old.

"So it does indicate that we are winding down," she said.

Another aerial survey will be conducted on Aug. 9 or 10.

Stinson said if no more carcasses are spotted, the outbreak would be declared over.

The first bison carcasses were discovered in the Slave River Lowlands on June 23.

All the carcasses have been burned.