The superintendent of Wind Cave National Park is urging drivers to slow down and use caution to avoid hitting animals while driving through the park in South Dakota's Black Hills.
Superintendent Vidal Davila says people driving at night or in poor winter weather conditions often have trouble seeing bison or elk on the road.
Davila says five bison, three deer and one pronghorn antelope have been killed in the park so far this year after being hit by vehicles.
The park superintendent says bison sometimes gather on highways in the park to lick salt. That salt is used on roads outside the park, but clings to vehicles and then drops off when those vehicles are traveling through the park.
Davila says the park has around 450 bison.