Deer are most active in the fall, and that can be bad news for drivers. The Missouri State Highway Patrol on Monday urged motorist to be vigilant, especially during evening and early dawn hours.

Fall is mating season for deer, and their numbers continue to grow in Missouri, even in suburban and urban areas.

Hunting and crop harvesting also tend to prompt deer to venture out into roadways.

The patrol says Missouri had 3,980 deer-related traffic accidents last year, with most occurring from October through December. Five people died and 411 were hurt in those accidents.

Motorists who see one deer should slow down and proceed cautiously because the animals often travel in groups.