Recent descents of Summit Mountain on Rte. 40 have offered too-close-for-comfort views of two fearless but fortunate deer. At the curve just above the runaway-truck ramp, a white-tailed doe and her single fawn have been grazing along the westbound shoulder, oblivious to motorists’ careening, lane-hopping race to Hopwood. Within any trip down lurks the dread that one, or both, might be smeared on the pavement. But, so far, they’ve survived.
They’re hard to miss—visually, that is—by drivers not more intent on passing every car they encounter. Both deer sport the brick-red pelage of early summer, and when the late-afternoon sun strikes across Pine Knob, their coats flame like a construction cone.
The fawn is beginning to get some bulk to it now, but the first couple of times I saw the pair, the youngster was a tiny frail thing that could barely part the grass in its mother’s wake. It will carry the familiar spots that help camouflage it from predatory eyes until about mid-September. Fawns are generally weaned from their mother’s fat-rich milk by 10 weeks of age—around mid-August.
Typically, a white-tailed doe has twin fawns, but several possibilities could explain why a single offspring trails behind the Summit Mountain doe. Yearling females that have conceived for the first time often have only one fawn, as do older does in reproductive decline. It’s also possible that the Summit Mountain doe lost one youngster to some predator. Recent studies of fawn mortality by Game Commission biologists document that coyotes, bears, and bobcats all take fawns when they can, especially during summer when young deer are most vulnerable. On the study areas in northern and central Pennsylvania, coyotes and bears preyed on fawns at about equal rates, while mortality from bobcats was much lower. Predation was determined to be the greatest source of mortality among fawns (about two-thirds of all deaths), but natural causes such as starvation, disease, and accidents also claim some deer in early weeks of life. Much of the study took place in remote forest far from high-speed roads, so did not consider highway mortality, which is clearly a factor along transport corridors.
Judging by the time the pair first appeared along Rte. 40, the fawn’s birth fits the ideal reproductive schedule in Pennsylvania. About 70 percent of all fawns here are born within 14 days of June 1, the peak of whitetail births. That sudden profusion of fawns in the forest increases the chances of each one to survive detection by predators. It’s a case of safety in numbers, in a way. Concentrating births around one peak date “overwhelms” bears and coyotes—they can’t find them all—ensuring that most fawns will survive the summer.
Those fawns born around June 1 were conceived seven months earlier, during the peak rut in early November. If fawn births do cluster around June 1, that indicates things are well-balanced in the whitetail herd. In the past, deer management in Pennsylvania was overly protective of females. As a result, the ratio of does to bucks became lop-sided in favor of females. That was a good thing, so to speak, for surviving bucks but it threw the species’ reproductive “plan” into chaos. When bucks are greatly outnumbered by does, some does are not able to be bred during their short receptive span. So, after 28 days, an unbred doe enters estrus again, but much later in the fall.
She may be bred during that second cycle, or even in the third, but the 7-month gestation period does not change. Therefore, fawns conceived late in the fall are born later the next summer—in July or even August. Those fawns are always smaller and weaker entering winter, less able to compete for limited browse, and easier for coyotes to catch in deep snow.
Allowing hunters to take antlerless deer—even multiple antlerless deer—keeps the ratio of bucks to does in better balance, resulting in a more natural and ideal birthing schedule.
Whitetail fawns are born in what biologists call a “precocial” state. That means they have an inborn ability to stand up and follow their mother within hours. But fawns continue to spend long hours hiding motionless while the doe forages nearby. If a doe has twin fawns, she will hide them in different locations while she feeds, so that a predator can’t find both at once.
The sex-ratio at birth slightly favors males, to compensate for males’ higher mortality rate through life (Males range more widely than females, so are more exposed to predators, disease, and accidents). Fawns weigh five to seven pounds at birth, and average about 18 inches in total length. By their first winter, deer born at the ideal time in early summer can approach 100 pounds in weight.
Every summer the Game Commission warns Pennsylvania residents not to pick up fawns they believe are abandoned by their mothers. In almost all cases, the doe is somewhere nearby, waiting for a secure opportunity to rejoin her young.
It is illegal to possess a wild deer, and fawns that well-intentioned people pick up may be doomed to a life in captivity. The mother will search for the fawn for a while, but will eventually give up leave, making reunion impossible. It’s almost always best to leave a fawn where you find it.
Ben Moyer is a member of the Pennsylvania Outdoor Writers Association and the Outdoor Writers Association of America.