Those deer-caused deaths, as far as we know, are not caused by deer-human hunting. The unfortunate result is that more than 2 million people a year plow into deer with their sedans and SUVs, usually on a two-lane road, often at high speeds.
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You may be wondering: Where and when am I most likely to hit a deer? And how can I avoid it?
To shed light on this vegan danger, we, of course, turned to the data. Specifically, we analyzed more than 1 million animal-vehicle collisions collected by Calum Cunningham, Laura Pugh, and their colleagues at the University of Washington for a recent paper published in Current Biology. They estimate that between 1994 and 2021, deer were involved in more than 90 percent of the collisions that occurred in 23 states.
With few exceptions, the data show deer are most dangerous in November. In fact, the deer threat peaks just before Thanksgiving — typically November 7th through the 14th — when you’re three times more likely to hit a deer than any other time of year.
Seasoned deer hunters can probably guess why driving in November can turn into Russian roulette on some highways and byways: In much of the country, it’s rutting season. And during the rut, deer focus on reproduction, not self-preservation. Marianne Gauldin of the Alabama Department of Wildlife and Freshwater Fisheries compares rutting bucks to teenage boys.
“They’re too focused on the opportunity to reproduce, and so they lose their intelligence,” Gouldin said. “What they’re doing is searching, chasing and running for an opportunity to breed. And they’re doing it with tunnel vision … literally running across the road.
shares similar confusions. They’re either in estrus — a hormone receptive to sex and looking for breeding — or fleeing hot and bothered bucks until their cycles catch up.
Collisions occur more often in states with more white-tailed deer — which experts say have shorter, sharper tracks than western mule deer — and in states with long stretches of busy rural roads. Separate insurance claims data from State Farm, widely cited in academic research, show the driver minding his own business. Vending, winding roads West Virginia has a 1 in 35 chance of hitting an animal between June 2021 and June 2022, making the Mountain State easily the most dangerous in terms of deer-car collisions. Montana and Michigan are next. DC drivers, by contrast, had only a 1 in 907 chance of stopping the buck on Pennsylvania Avenue or anywhere else.
Fun fact: According to State Farm, deer are responsible for at least 69 percent of animal-related accident claims. Another 12 percent of claims involve unidentified animals, many of which may be deer, that may have been too blinded before the driver got a good look at them, or in an accident.
The third-most-dangerous animals on the road are non-segregated rodents, cited in 5 percent of all animal-related accident claims. However, State Farm spokesman Dave Phillips noted that many drivers never come into contact with said rodents: Most of those accidents occur when motorists swerve to avoid a suicidal squirrel or a moosing marmot.
Our more calendar-conscious readers will note that the deer-accident period coincides with another big moment in November: the first week of daylight saving time, which begins on the first Sunday of the month. And a team from the University of Washington found that the two events are not related.
To understand why, we need to delve deeper into their data, which breaks new ground by including the exact location, date and hour of all these deer disasters. When we glance at the accident chart, which includes time of day and time of year, one truth strikes us between the headlights: evening, every day is twilight – especially in November! – It’s the hour of Götterdeermerung.
Conveniently for us, scientists at the University of Washington use accidental coordinates and some basic weather math to calculate exactly when the sun will rise or set in each location. It turns out that deer danger skyrockets about 30 minutes after sunset and remains unusually high for about half an hour.
Deer-behavior experts say drivers need to be extra cautious as it gets dark in the fall — especially when careening through deer’s favorite transitional habitats, the forest-edge ecosystem created by roads and other developments. But they urge us to take a lesson from the thousands of people who land in hospitals and body shops every year after trying to avoid a turtle or a chipmunk: If you see a deer, don’t turn around.
“Obviously, slow down as much as you can,” said Karlyn Gill of the National Deer Association, a hunting and conservation organization.
Deer accidents also peak in the morning about 30 minutes before sunrise, but numbers drop significantly after sunset. To understand why, we need to dig deeper into patterns of deer and human activity.
Biologist after biologist told us that deer are crepuscular, meaning they are most active at dawn and dusk. When Texas A&M University wildlife scientist Stephen Webb and his colleagues installed GPS trackers on white-tailed deer in Oklahoma, they found peaks in deer movement at sunrise and sunset.
“Deer, like humans, don’t sleep eight hours a night and then get up and move all day,” said Gill, who, as a hunter, closely examines deer behavior. “They actually go through a cycle where they sleep, sleep, wake up, eat, sleep, sleep, wake up, eat, and they do this over a 24-hour period.”
But if deer are equally active at dawn and dusk, why are they more likely to strike in the evening? To top it off, we need to examine another slightly crepuscular species: the American traveler. Our trips peak in the morning and evening, but we’re more likely to drive at dusk than early in the morning, and we’re still on the roads when it gets dark and the deer start moving — often in our headlights.
It’s a matter of visibility. Deer are active two hours before dusk, but they are 14 times more likely to hit deer after sunset than before.
And, as Cunningham notes, at the height of the whitetail rut, we throw another variable into the stew: We end daylight saving time. Suddenly, as far as the deer are concerned, our 6pm journey happens an hour later. Millions of drivers are struggling with reduced visibility just as sex hormones flood the local deer population.
“It’s one of those large-scale natural experiments where humans impose these arbitrary and sudden changes on wildlife,” Cunningham told us from his native Tasmania (he’s a Fulbright fellow at the University of Washington. ).
People living on the far eastern side of the time zone are about 1.35 times more likely to hit a deer than people on the far western edge, because people in the east are more likely to drive home in the dark. Similarly, people in northern states, where days are short and darkness rules the winter, are 1.86 times more likely to hit a deer than their friends in America’s sunny south.
Taking these effects into account, the University of Washington team estimated that “falling behind” caused a 16 percent jump in deer kills in the weeks following the shift. Adopting permanent daylight saving time has the potential to save lives More than 36,000 deer and 33 humans each year.
On the down side, University of Surrey chronobiologist Eva Winnebeck argues that any gains could be offset by the increase in deaths from chronic drowsiness that would inevitably result if our solar-driven circadian rhythms were forced to endure a never-ending state. Disconnect between the sun and clocks permanently set to daylight saving time.
Here in the data department, we’ve found a strong connection between happiness and the outdoors. So we’re partial to any move that gives us more daylight hours to get out after work and fish, run or dominate the competitive tree-drinking circuit, circadian rhythms be damned.
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