White-Tailed Deer Mating and Reproduction at Devils Tower

A female White-Tailed Deer standing in front of a large rocky outcropping on top of a hill with grass and pine trees.
A White-Tailed Deer standing in front of Devils Tower.

NPS/ Andrew Landry

White-Tailed Deer at Devils Tower
White-Tailed Deer are a keystone species, directly affecting the other wildlife and environment at Devils Tower National Monument. A White-Tailed fawn is a remarkable example of how a prey animal is taught to avoid danger and survive in the wild while constantly being hunted. This article highlights how White-Tailed Deer breed and raise offspring.

White-Tailed Deer Mating
The mating period of White-Tailed Deer lasts from late fall to winter, depending on the location of the population of deer in the country. For instance, a deer at Devils tower will breed in a different month of the year than a deer in the southern United States. What triggers the breeding season is the changing of photoperiod, the amount of daylight in each day. A female White-Tail (doe) comes into heat (sexually receptive and ready to mate) during a 24-36 hour time frame, where the male (buck) smells that she is in heat and will single her out and try to breed. The doe will not breed until she is ready to breed. If she does not breed the first time she comes into heat, she will come into heat again 28 days later during the mating season.

Bucks spar (use their antlers to fight), rub their antlers and tops of their heads on trees, and scrape the ground, moving leaves and getting to bare dirt. These behaviors are different ways to spread scent and display dominance so that dominant bucks get their choice of does that come into heat in the area. A buck will breed with multiple does in one breeding season.
A mature White-Tailed buck standing in tall grass with trees and snow in the background.
A mature White-Tailed buck during the breeding season.

NPS/ Andrew Landry

White-Tailed Deer Fawns
A doe’s gestation period (time she is pregnant) is around 200 days. After that, she delivers her baby, a fawn. A White-Tailed fawn is new to the world and can stand quickly after birth (within a couple of hours)! Fawns weigh about 6-8 pounds when born and have a reddish-brown coat with white spots, helping them camouflage in their environment. A fawn will nurse by drinking its mother’s milk. In that time, they learn what vegetation to eat from their mother while being weaned off the milk. Depending on the doe’s age, health, and size, a doe will typically have one to two fawns per year, however three and four fawns have been recorded. White-Tailed Deer have offspring once a year.

A fawn is born very defenseless to the world. They cannot fight back from predators. Fawns cannot even run away from predators until they are strong enough to do so. Their best chance of survival is by laying very still in a very safe and protected area that their mother puts her baby in, hiding in tall vegetation or deep in a forest usually. The mother will leave her fawn for hours at a time for the first few weeks. This allows the doe’s scent to not rub off on her baby, allowing the fawn to be nearly scentless, not allowing predators to be able to smell and then find the fawn, thus saving the fawn. The doe will come to her baby periodically in a day to nurse and move the fawn(s), never straying too far from her offspring. The mother teaches her fawn(s) to be quiet and hidden from danger. As the fawn grows, it will eventually keep up with its mother and be strong enough to run away and avoid predators.
A baby White-Tailed Deer laying still on the ground in tall grass.
A newborn White-Tailed fawn lying still in tall grass.

NPS Photo

The Future of White-Tailed Deer
A newborn, watermelon-sized fawn grows up to be a majestic and beautiful adult White-Tailed Deer, like the one shown below. It is important to let wild animals remain wild and to protect the wilderness that deer and other wildlife inhabit. By not decimating predator populations, we ensure that the populations of White-Tails remain in check and overall help protect deer from diseases, such as Chronic Wasting Disease, that occurs when there are too many deer and no predators to regulate them. By protecting the habitat in which they live, White-Tail populations can flourish. By respecting the ecosystem, we help protect White-Tailed Deer populations for years to come.
A White-Tailed doe with a grassy background.
White-Tailed doe growing into an adult.

NPS/ Andrew Landry

Last updated: March 27, 2023