Run, Jump and Play: a Look at Deer Agility and Jollity

Faster than a speeding bullet?

More powerful than a locomotive?

Able to leap tall buildings in a single bound?

While it may seem to the average deer hunter that whitetails have supernatural abilities akin to our favorite comic book hero, deer do regularly use their speed and agility to navigate dangerous situations; like escaping from predators or other intruders, chasing competitors or potential mates, and to access better locations of cover or food – think, your not-quite-high-enough fenced garden, a nearby orchard or that farmer’s field down the road full of standing corn. 

What’s more, many of the non-hunting public understands the importance of hunting as a means to population management and accept and approve of it as long as the meat is being used — but personally draw the line at participating themselves, even if they eat meat. Often, at some level, that line is there as a result of the person humanizing the animal. However, beyond the “cuteness” factor and probably even evidence of maternal behavior (I’m not Freud, so I’ll steer clear of bringing up your relationship with your mom. Oops.), likely one of the primary reasons this anthropomorphic view exists is that we commonly observe a sense of playfulness in deer and other wildlife.   

As we often do here at QDMA, let’s take a look at what science says about the limits of a deer’s physical ability, and how or why “play” happens.

Run

Just how fast is a white-tailed deer when running full speed? According to Leonard Lee Rue III in his 1978 book The Deer of North America, a whitetail’s top speed is just shy of 40 miles per hour (mph). Now, while I don’t know exactly how this was measured, the estimate was later cited in an international, peer-reviewed study funded by the National Science Foundation and published in the Journal of Zoology, London. Knowing full well how that adds to the credibility of such a statistic, I’ll take it at face value that it’s accurate.

In this same paper, whitetails were ranked among a litany of wildlife including other hooved North American big game animals, such as pronghorn antelope (62 mph), mule deer (38 mph), moose (35 mph), and bighorn sheep (30 mph).

Jump

I’ve seen it stated in a few places that deer can leap as high as 10 feet high and as far as 30 feet in a single bound. But how true is that? Luckily a couple of recent studies examined a whitetail’s maximum jumping height, which will help answer this question.

They actually caught wild deer, tested their ability to jump progressively taller fences, and found that the top end they could jump was just under 8 feet (2.4 meters).

In 2010 Kurt Vercauteren and his co-authors published the paper “Assessment of Abilities of White-tailed Deer to Jump Fences” in The Journal of Wildlife Management due to growing concerns of disease transmission around captive deer facilities and increasing prevalence of agricultural damage and deer-vehicle collisions. They actually caught wild deer, tested their ability to jump progressively taller fences, and found that the top end they could jump was just under 8 feet (2.4 meters). They found that surprising since so many people claimed deer could jump higher. So, after the study was complete, they then surveyed over 150 wildlife biologists who routinely observe and work with deer near fences and found only 6 who had witnessed a deer jump a fence higher than 8 feet.

The following year, Drs. Karl Miller and Gino D’Angelo and their colleagues at the University of Georgia compared several fence designs (including wire and solid material) for excluding deer from roadways as part of a study published in Human-Wildlife Interactions. Regardless of fence design, they also found that the 8-foot design excluded all research deer, and that you can even lower the fence height a little if you add an angled “outrigger” to the top in the direction deer travel is expected to come from.

So, how high can a deer jump? Apparently, the vast majority can only clear a fence 7 feet or lower.

Play

What about deer playing? What’s the deal with that?

You’ve likely observed it one time or another. Looking from afar as two fawns run and frolic across an open field at sunset. Or, find yourself watching that instant-messaged video link of a young deer chasing (and being chased by) a chihuahua.

Well, believe it or not a lot of work has been done on animal play. And, for good reason. There are a lot of theories about why animals play, but scientists have yet to really peg the exact reason. And, because all those YouTube videos don’t make themselves, it clearly happens enough that we all see it regularly. In fact, Leonard Lee Rue wrote, “although hoofed animals do not engage in play as often as do some of the other mammals, notably predators, they do play far more often than most people suspect.”

Immature animals, like these two button bucks, probably use play to fine-tune their future responses to actual stress.

Let’s begin with what “play” is, and then we will dive into why we think deer and other wildlife partake in it. Gordon Burghardt, a biologist at the University of Tennessee, developed a scientific definition for play; according to him, play is a “repeated, pleasurable behavior done for its own sake that’s similar, but not identical to, other behaviors in which the animal regularly engages. It also must be performed when the animal is healthy and not under stress.”

That last part is key and is one of the leading theories why deer play.

Researchers know that when a young animal experiences stress, its brain changes so that it’s less sensitive to stress hormones in the future. This means that as an adult the same individual recovers more rapidly after a hair-raising experience.  Because of research done by Stephen Siviy, shared in the book Animal Play: Evolutionary, Comparative, and Ecological Perspectives, we also know that play, which normally consists of stimulating flight-or-fight behaviors, activates the same neurochemical pathways as stress; thus, it’s very possible that immature animals use play to prime or fine-tune their own future stress response.

The other thing we’ve found is that when a young animal plays, the more rapidly its brain grows and the quicker they learn. “Researchers teased apart the factors that promoted brain growth and found that sensory stimulation and arousal (even together) couldn’t increase cortical growth unless they were coupled with interactive behavior (i.e. play or training). And it was play that had the biggest impact,” said Lynda Sharpe in a 2011 Scientific American article entitled So You Think You Know Why Animals Play.

So, the next time a viral video hits your inbox of a yearling buck kicking a beachball, know that it’s not a fresh, non-speaking version of Rudolph getting ready for the Reindeer Games, but that science says he’s likely just engaging in the miracle of growing up to become an adult deer.


About Matt Ross

Matt Ross of Saratoga Springs, New York, is a certified wildlife biologist and licensed forester and QDMA's Assistant Director of Conservation. He received his bachelor's in wildlife conservation from the University of Massachusetts-Amherst, and his master's in wildlife management from the University of New Hampshire. Before joining the QDMA staff, Matt worked for a natural resource consulting firm in southern New Hampshire, and he was a QDMA volunteer and Branch officer. He and his wife Sadie have two daughters, Josephine and Sabrina.