Conservation officers say woodland bison have started hanging around the Alaska Highway, endangering drivers, particularly at night when their dark brown fur blends well with the shadows.

Bison were re-introduced to the Yukon in the mid-1980s and early-1990s as part of conservation efforts to protect the nearly extinct species.

'We're restoring an animal that has traditionally been on the landscape and arguably belongs there,' explained biologist Tom Jung with Yukon's Department of Environment.

The goal was to have around 500 woodland bison in the Aishihik and Hutshi area, but a lack of predators has allowed the herds bison herds grow much larger.

'We do know for sure they've exceeded 500,' said Jung.

In July a count tallied 640 animals but the precise number of bison remains uncertain.

In time it is expected that wolves and bears will begin to hunt the animals as they did in the past , and still do in other parts of North America. But so far that isn't happening in Yukon, explained Jung.

'We're pretty sure they will.'

Jung said in Yellowstone National Park, wolves are known to hunt bison. Bears are known to hunt the calves.

'Some (wolves) in the Northwest Territories specialize in hunting adult bison,' he said. 'We do suspect wolves will start taking bison if they don't already. They probably need some time to learn.'

Until that happens, the only thing keeping bison numbers in check are hunter's bullets and that becomes even more necessary when the bison start hanging out around Yukon highways, said Jung.

There have been a few small herds of bulls and one larger herd of 25-30 bulls and cows foraging beside the Alaska Highway between Kusawa Lake Road and Medenhall subdivision (Kilometres 1490 and 1546, respectively).

So far, two vehicles have been involved in accidents with the bison, said conservation officer Dan Drummond.

While no one was seriously injured, Drummond said the second accident, which happened just Sunday night, left the vehicle inoperable and the bison undamaged.

'He seems to have survived which isn't unusual.'

Highway corridors are attractive to bison because of the foliage and easy travelling route.

Conservation officers are concerned the small groups currently feeding there may grow into larger groups in future years.

To keep that from happening the department has permitted a few resident bison hunt permit holders to begin this year's season a bit early.

Accompanied by conservation officers, the hunters are being permitted to hunt the bison along the highway.

According to a press release, two bulls were killed along the Alaska Highway Sept. 30, and four more were taken over the last two days. A total of six bulls and two cows have been taken.

Conservation officers elected to have hunters take the animals after efforts to scare them from the highway with rubber bullets and cracker shells failed.

Members of the Champagne and Aishihik First Nations and permit holders participated in the hunt.

Bison are the largest land animal in North America. They can weigh up to 2,200 lbs or just under a metric tonne. That's a little under 300 kilograms less than a bull moose, he said.

'Some of these bison weigh more than the cars on the road,' said Jung.

Drummond said the large herd appears to have moved away from the highway and he was unable to say whether more permit holders would be allowed to participate in the early hunt.

'We have to play it by ear. The whole objective is to get these animals off the road.'

If the bison leave the highway area the early hunt will be stopped, he said, adding all animals taken will be subtracted from the annual number of animals hunters are allowed to kill this year.

The hunt, said Drummond, is a message to the bison that highways are a bad place to hang out.

'If we fail in giving them that message we may have a bigger problem next year,' he said.

Drummond added night is the most dangerous time to drive as far as accidents involving wildlife goes.

All recent wildlife accidents, including several involving elk, have taken place during the hours after sunset, he said.