When Do Collisions with Wildlife Occur?

 

It is important for motorists to have information about the factors that influence animal behaviour. This will lead to an increased level of understanding about when, where and why wildlife is most likely to be present near the road.

 

Animals are active 24 hours of the day, and all year round, but past records kept by the Insurance Corporation of British Columbia (ICBC) and the BC Ministry of Transportation (BC MoT) Wildlife Accident Reporting System (WARS) show that there are some peak times when wildlife vehicle collisions may be more likely and drivers should be especially alert.

Time of Day

In the Southern Interior of BC, data from ICBC shows that about 45% of all collisions with wildlife occur between 7:00 p.m. and midnight.

 

In Alberta, over the last 5 years, 35% of all collisions involving animals occurred between 7:00 p.m. and 11:00 p.m. Fridays have 15.8% of all collisions.

 

Most literature suggests that dusk and dawn are traditionally times of high wildlife vehicle collisions. Light levels are low, and animals are active at these times.

Time of Year - Month

This information is taken from WARS 1983 - 2002, Wildlife Accident Reporting and Mitigation in British Columbia, Special Annual Report. Other jurisdictions may have different time periods that are high risk for wildlife collisions.

 

Approximately 80% of wildlife vehicle collisions involve deer. There are two distinct high risk times for deer crashes. May and November have the highest rates of deer accidents.

 

Infra red and video footage of deer crossing busy roads in Britain is supplied by Jochen Langbein of the National Deer Collisions Project. Note the number of animals present and the risky behaviours.

• Red Deer
• Fallow Deer

Moose are involved in approximately 8% of all wildlife vehicle collsions. Due to the extremely large size of these animals, (a mature bull moose may weigh up to 500 kg - 1200 lbs), there is a 1 in 100 chance that a moose-vehicle collision will result in a fatality. Moose collisions peak in December and January, with the rest occurring between October and March. Accident peaks coincide with times of high snowfall along highways that are actively cleared of snow. There is also an accident peak in June/July, which may be due to pregnant cows moving to calving grounds.

 

In this collision, the moose hit the bumper, bounced onto the roof, rolled onto the trunk, and then fell onto the road. The driver sustained serious neck injuries.   Photo courtesy of Fort George Highway Rescue Society. Collision occurred on Highway 97, north of Summit Lake, 2004

 

Approximately 3% of wildlife vehicle collsions involve elk, which have collision patterns similar to moose. There is an accident peak between October and February, with a secondary peak in May and June. The winter peak coincides with times of high snowfall, when elk are found beside the highways.

 

	Elk on the Bow Valley Parkway, Banff National Park. Photo courtesy of Christine Aikens
	Roosevelt Elk Photo courtesy of Jim Robertson www.animalsinthewild.org
	Bull Elk Photo courtesy of Jim Robertson www.animalsinthewild.org

 

Bear are involved in approximately 3% of all collisions. September and October are the peak times for bear-vehicle collisions. There is a depletion of natural food sources at higher elevations near the end of summer which causes bears to move into the valley bottoms in search of food.
	Dead black bear on Deadman Flats, Highway 1, just east of Banff National National Park, AB Photo courtesy of Ernie Kroeger

 

 

Bighorn sheep are at high risk of collsion between November and February, with intermittent peaks in April, June and September. In the early summer, bighorn sheep begin to move out of the valleys, feeding near the highways, on their way to higher elevations for lambing. In the fall, they begin to move back in preparation for the rut.

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Time of Year - Season

Spring

The early green up of vegetation in the ditches along the side of the road, is an attractive source of forage for many wildlife species, and is a major factor in one of the highest risk times of the year. Also, the birthing season means that there are many inexperienced animals near the roads. About half of deer fatalities occur in the spring.

 

Summer

Forest fires which destroy habitat; drought; and dry, hot weather that reduces forage availablity at higher elevations, all cause increased animal movement at this time of year.

 

Fall

Many animal species are on the move during the the mating season causing an increased hazard. Animals "in the rut" may exhibit erractic or aggressive behaviour.

 

Winter

As snow levels increase at higher elevations, animals move to their winter range in the valley bottoms. Many human transportation corridors are located in these same valley bottoms. Road salt attracts wildlife onto the road surface and rights of way. Once animals are on or near the road, their ability to move off the road can be impaired by snow accumulations due to plowing.

 

Click here to view and/or print an FAQ list about wildlife vehicle collision prevention [PDF - 45 kb]

 

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