Illinois Drivers Should Be On Lookout During Deer Mating Season

WILL COUNTY, IL — This time of year may be spooky season, but drivers also need to be alert for deer crossing local roadways.

The Forest Preserve District of Will County said peak mating season for deer is approaching.

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For white-tailed deer, peak mating season – called a rut – is late October to mid-November, the preserve said. During this time, deer tend to move about more freely, causing an uptick in collisions with vehicles.

These collisions are second only to hunting in causes of deer mortality in Illinois, according to Wildlife Illinois.

"Deer are plentiful across Illinois, and drivers should be aware of their presence," Illinois Department of Natural Resources Director Jim Montgomery said in a news release. "Please be cautious while driving, as deer are notably active during fall mating season and around dusk and dawn."

In 2025, 14,529 motor vehicle crashes in Illinois involved deer, according to the news release. Of these, 13,846 caused damage to property or vehicles, and 677 resulted in injuries. Six of the crashes were fatal, resulting in seven deaths, according to the news release.

Last year, 41 percent of crashes involving deer occurred in October, November and December, with November being the month with the most deer-vehicle collisions. Eighty percent of all collisions with deer were at twilight or nighttime.

Will County ranked fifth for the top Illinois counties for crashes involving deer in 2025. Will had 342 crashes, behind Sangamon County, which had 355 crashes.

Cook County had the most crashes involving deer, with 559 crashes.

Eight out of 10 collisions were at twilight or nighttime, according to the news release.

Deer populations can thrive in rural, suburban or urban environments, IDOT said.

"Be aware of your surroundings, especially in areas with deer crossing signs," a news release shares.

Other tips from IDNR and the Illinois Department of Transportation include the following:

• Scan the sides of the roadway for eye shine, which indicates their presence.
• Slow down if you see a deer. Anticipate others will be nearby; they often move in groups.
• Be ready for the unexpected. Deer may stop in the road and may not move for oncoming vehicles.
• Always wear your seatbelt. It's your best defense in any crash.

"Deer are on the move throughout the state, increasing your chances of encountering one at any time," Illinois Transportation Secretary Gia Biagi said in a news release. "Stay alert, even during routine trips and your daily commute. Following a few simple recommendations and rules can help you avoid a trip to the body shop – or worse."

In the event you do hit a deer, pull your car off to the shoulder if possible and turn on your hazard lights, the state advises. Call 911 to report the accident and request emergency assistance. Do not exit your car to try to check on the deer or remove it from the road.