Winter, with its lack of crowds in most parks, can be a great season for a visit ...with a caveat. While the need to use caution on snowy and icy highways should be obvious, another potential hazard may not be on your mental radar during a winter drive: wildlife on the road.

A park spokesperson for Wind Cave National Park points out that, "The combination of winter weather, night driving and hard-to-see animals can make for hazardous driving conditions at Wind Cave"... and the same is true at a number of other parks around the country.

"A bison lying or walking on the road can be very difficult to see at night and almost impossible to see in poor weather conditions," said Wind Cave Superintendent Vidal Davila. "We encourage all drivers to adjust their speeds to the conditions and operate their vehicles with safety in mind."

"During winter months, especially in snowy conditions, wildlife patterns change," the Wind Cave advisory notes. "It is not uncommon to find bison along the highways licking salt used on roads outside the park and deposited inside the park by passing vehicles."

Salt isn't the only reason you may see more animals than you might expect, on and along the road. Heavy snow can cause wildlife to move to lower elevations and closer to roads in search of food. Between October and mid-January last winter, at least 27 large animals were killed on major highways in Jackson County, Wyoming, which includes Grant Teton National Park.  Each of those collisions also represents a toll on humans and their vehicles. One local wildlife expert said those numbers were higher than usual, perhaps as a result of the heavier than normal snowfall.

In parts of the country where significant snowfall occurs, plowed roads can become easier travel routes for wildlife, but there's a downside for the animals as well. Snow removal operations can create deep snow banks along both sides of the pavement, making it hard for animals to get off the road when vehicles approach. If you see an animal on or near the road, don't assume it can or will move out of the way.

The situation can be a serious one for humans as well as wildlife. Accidents involving large wildlife have the potential to cause serious injuries or death to drivers and their passengers, and the animals are usually casualties as well. Depending upon the part of the country, bison, deer, elk and moose can all pose hazards on the road.

Wind Cave's Davila notes, "In the last five years, 48 large animals, primarily bison, have been killed as a result of vehicle collisions in the park. Sometimes even driving the posted speed limit is too fast for conditions and people need to slow down."

The park staff at Wind Cave recently installed radar speed signs at both entrances along Highway 385 in an attempt to remind drivers to reduce their speed. About 400 bison live in the park.

Other parks and local partners are teaming up to encourage drivers to slow down and be alert for wildlife during all seasons of the year. The Jackson Hole Wildlife Foundation, for example, has been working with Grand Teton National Park and other locations to distribute a Wildlife-Vehicle Collision Awareness flier. The organization notes, "Each year, more than 300 elk, deer and moose are killed by vehicles on Teton County and Grand Teton National Park roads.  Vehicle collisions also kill foxes, coyotes, bears, and birds."

A British Columbia website for The Wildlife Collision Prevention Program includes some excellent information on this subject that's applicable to roads in and outside of parks in both countries. For example, the site notes that "Wood Bison generally stand with their head lowered. This means that although Wood Bison eyes can reflect light back at approaching vehicles, it seldom happens. Drivers should not expect to see glowing eyes in the dark."

Officials in parks on both sides of the border have the same message for winter drivers: slow down and be alert for wildlife. The posted speed limit isn't always a safe speed, especially in winter.