You are on your way home from work, driving down a quiet road. It’s autumn, so the sun has already set, casting everything in darkness even though it is only 6 p.m. Suddenly, two pinpricks of white light appear in the distance. Is it a reflection of your headlights? Before you can determine the source of light, your car has hit something. There’s a shattering, hollow thump as you are involuntarily jolted backward in your seat.
You have hit a deer. A creature is now dead, gruesomely bleeding out on the road. Once the adrenaline in your veins and your fear dissipates, you are able to examine the damage to the car. Your shock absorbers are shot, the fender has been crumpled up like a piece of paper, there’s a gaping dent to the hood, and you haven’t even taken a look at the motor. Repairs will cost thousands of dollars.
A new study contends that switching to year-round daylight saving time would significantly reduce the number of deer and vehicle collisions, leading to the saving of human and deer lives and billions of dollars in collision costs. As it stands now, over 2.1 million deer and vehicle collisions happen yearly, causing more than $10 billion in damages, 440 human deaths and 59,000 human injuries.
The study, published on Wednesday in the peer-reviewed journal Current Biology, estimates that if the United States halted the switch from standard time to daylight saving time in autumn it would prevent the death of 36,550 deer, 33 humans, the injury of 2,054 humans and save up to $1.19 billion in collision costs annually.
“The numbers are surprisingly large,” said Laura Prugh, an associate professor of wildlife science at the University of Washington and an author of the study, per NBC News. “It’s just noticeable that a seemingly simple change — not changing the clock back in the fall, not falling back — would lead to such a marked reduction in collisions throughout the country.”
Compiling data from 23 state agencies, the team analyzed 1,012,465 vehicle collisions with deer from between 1994 and 2021, finding that they are 14 times more frequent within the first two hours after sunset. Furthermore, the switch from daylight saving time to standard time during autumn causes peak traffic time to occur after dark rather than before, leading to an increase of 16% in collisions with deer.
Calum Cunningham, a biologist with the University of Washington School of Environmental and Forest Sciences and an author of the study, stated in a press release, “It was surprising how striking this pattern was, of how much more likely deer are to get struck in the hour or two after darkness. This one-hour shift in human activity could have such a significant effect.”
The time switch occurs at the worst possible time for deer — mating season. During mating season deer, particularly males of the white-tailed deer species, are significantly more active. Researchers found that collisions with deer rose by 16% during the first week after the switch. “It’s like the perfect storm. These deer are going crazy. They’re really most at risk already and we have this additional change of adding more driving after dark in this switch,” Cunningham explained.
The study arrives as the question of whether to daylight saving time is being debated within the federal government. The Sunshine Protection Act, passed by the Senate in 2021 and awaiting confirmation by the House, would by November 2023 make daylight saving time permanent year-round in all states except Hawaii and Alaska. The act has been criticized by health officials and sleep experts, while many researchers hope the change would lead to fewer vehicular crashes.
Prugh told USA Today that she hopes Congress will take the study’s findings into consideration when deciding how to proceed. “This is one fairly consequential factor for both wildlife and people that hadn’t been considered before,” Prugh said. “It turns out it makes a pretty big difference. I just hope they (Congress) will seriously consider this aspect.”