Deer mating season is at its peak through December. Here’s what drivers need to know

A deer stands near a path at the Abraham Lincoln National Cemetery in Elwood on Saturday, July 29.

Along with the holiday season comes deer mating season, which means the risk of vehicles colliding with a buck or doe that’s wandered into the roadway is higher than any other time of the year.

Illinois ranks 11th in the nation for the number of State Farm claims insurance filed by drivers who struck an animal. Meanwhile, Cook, Kane, Lake, McHenry and Will counties were among the top 10 in the state for most deer crashes last year.

Crashes involving deer peak during breeding season, which runs from October through December. In 2022, more than 40% of crashes involving deer in Illinois occurred in October, November and December – November was the highest-risk month.

Last year, there were 14,524 crashes involving deer in the state. Of those, 13,892 resulted in damage to property or vehicles, and 629 caused injuries, including four deaths.

Erik Neidy, director of natural resources at the Forest Preserve District of DuPage County, said it’s mating behavior that drives the increased deer activity.

“The males are looking for mates, and it’s a competition,” Neidy said. “They’re chasing females, running around and pushing other males out of their territories. They’re active all year long, but at this time, they’re chasing each other around, literally. That’s what happens when they’re running across the road.”

Neidy cautions drivers to reduce speed and be extra vigilant during dawn and dusk, when deer are most active. They’re most common along woods, fields, fence rows and waterways.

Here are some additional safe driving tips, according to the forest preserve district and the Illinois Department of Natural Resources:

  • Look for deer-crossing signs, which mark areas where collisions are likely to occur.
  • Scan the sides of the road for eye shine – the reflection of headlights in deer eyes.
  • If you see one deer, be on the lookout for more. They can move in pairs or larger groups.
  • Don’t use your horn unless a collision looks inevitable. Distant noise may confuse the deer. Close noise may produce an extra burst of speed from the animal, but there really is no way to predict how a deer will respond.
  • Do not swerve to avoid deer – it could result in a more severe crash. Slow to a stop and wait. Flash headlights to encourage the animal to move.
  • If a collision is inevitable, try to glance your vehicle off the deer and avoid swerving into the opposite lanes of traffic or off the road.
  • If an accident does happen, don’t attempt to remove dead or injured deer from busy roads. Contact local law enforcement for help. Under Illinois law, drivers must report to police any deer-related incident with more than $1,500 in damage.

Deer in Illinois are overpopulated and have been for decades, Neidy said.

“That’s been documented for decades in regards to the number of animals per square mile,” he said. “It’s something that we have done through our own research, as well as through the state. Whitetail deer don’t have a natural predator, so it’s something we deal with here at the forest preserve.”

The agency is in its 31st year of a deer management program. Like in other forest preserve districts, including Cook County’s, the program includes the use of sharpshooters through the U.S. Department of Agriculture Animal and Plant Health Inspection Service.

“We manage our deer populations at 20 deer per square mile,” Neidy said. “When they exceed that, that’s when we utilize the removal program. Some preserves, it’s going to take us years to get there. It’s a program that will likely have to be done in perpetuity.”

Sharpshooters run evening operations when the preserves are closed, with activity typically lasting between November and March.

By state law, the district must donate all resulting ground venison. In DuPage County, it goes to the Northern Illinois Food Bank.

• Jenny Whidden is a climate change and environment writer working with the Daily Herald through a partnership with Report For America supported by The Nature Conservancy. To help support her work with a tax-deductible donation, see dailyherald.com/rfa.

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