• Columnists

Wildlife, ‘relative’ impact of Daylight Saving Time

• John Lorson: The Rail Trail Naturalist
• March 7, 2020
• 1790

By the time you read this column, your day might already be a little bit brighter, or at the very least it’ll seem a little bit longer as Daylight Saving Time will have added an hour of sunlight to your afternoon. And while Daylight Saving Time is an entirely human construct (first widely adopted in Germany and Austria in 1916 to save fuel for the war effort), it does have an effect on the animal kingdom as well.

I can almost hear you now: “How on earth can animals that can’t even tell time be influenced by the changing of a human clock?” The answer can be summed up in the simplest definition of a word made famous by everyone’s favorite theoretical physicist and all-around smart guy, Albert Einstein — relativity!

Fortunately for all of us, I am not about to delve into physics today. The relativity of which I speak is quite simple and totally literal: It’s the relationship of one thing to another. Daylight Saving Time affects animals because it has an effect on us. Our movements and activities change relative to those of the animals that live around us.

Wildlife moves to the beat of its own internal drum, dictated largely by circadian rhythms (or those that follow a 24-hour cycle); however, we humans tune our activities to the clock on the wall. Two times a year, once in the fall and once in the spring, our level of activity changes dramatically and literally overnight while wildlife continues along its regular 24-hour path. One need only consider the morning and evening ramblings of the white-tailed deer for a perfect illustration of the potentially catastrophic consequences of a sudden swing in the human schedule.

I leave work at about 6 p.m. at this time of year, and when I do, I nearly always encounter the same group of eight doe deer, wide-eyeing me as I ride my bike up the trail. As crepuscular animals, or those that are most active at dawn and dusk, they’re just gearing up for the day’s second round of dashing about the woods and across the roads.

I’ve watched this herd cross the busy state route that runs parallel to the trail dozens of times, and it never ceases to amaze me how they’ve survived this long living so close to all that traffic. While Millersburg isn’t necessarily a metropolis, there is a pronounced “rush hour” that has just begun to taper off by the time my does get going. When DST begins, their lot in life will become considerably better because the traffic leaving town will have already done so a full hour sooner relative to the deer’s daily ramblings. The odds of making it safely across the road go way up.

Now let’s flip the situation to the fall when those same deer have become long accustomed to darting across the road day after day for weeks on end right around the lightly trafficked hour of 6 p.m. When the human clock suddenly turns back to Eastern Standard Time, those same sunset-darting deer find themselves crossing the road at the very height of rush hour. That’s when bad things happen to good deer — and good people in cars and trucks as well.

Not all of these Daylight Saving Time inspired changes are bad. My morning ride will now begin an hour earlier relative to the schedule of the trail’s wildlife, and if my experience holds true, I’ll be encountering all sorts of critters that have been happy to go about their business without my intrusion for the past several months.

Of course beyond all of this time mumbo-jumbo, the minutes of daylight have been increasing notably, and that has inspired a whole new wave of activity in the animal kingdom. There should be plenty of things to tell you about in the coming weeks.

Write with comments or questions about the natural world to The Rail Trail Naturalist, P.O. Box 170, Fredericksburg, OH 44627, or email jlorson@alonovus.com.