White-tailed deer (Odocoileus virginianus) can be found in southern Canada, throughout most of the United States and into South America. They can live in a variety of habitats, but prefer dense thickets that provide cover and grazing at the edges. These dainty, yet athletic deer, have developed a range of adaptations to help them cope with seasonal changes, to evade predators and survive throughout the different stages of their lives.
The fawns rely on physical and behavioral adaptions to help them survive their early weeks. Their mothers leave them hidden in the vegetation while foraging, as the does' presence may attract predators. When there's more than one fawn, they can be left up to 200 yards apart. The fawns are virtually scentless and their reddish-brown coats, covered with pale spots, merge with the dappled sunlight on the forest floor. They instinctively remain still if any animal comes near them. The fawns won't pass feces or urine until their mothers return. The does then ingest their fawns' waste so no sign of their young is left for predators. The female deer also regularly change the fawns' locations. At 3 weeks old the fawns are able to forage and run from danger with their mothers.
The eyes of white-tailed deer are located on the side of their heads. This gives them a wide field of vision for spotting predators. While their large, cupped ears that move in different directions amplify noises and help the deer pinpoint where sounds are coming from. When running, they can hear if something is chasing them and hear anything moving in front of them. White tails' sense of smell is excellent. With just a slight breeze, they can pick up a predators' scent from 150 to 200 yards. Plus a large part of their brains are devoted to receiving and interpreting these scents.
Defenses in Their Legs
White-tailed deer are fast and agile. They have long legs, with strong muscles and ligaments, adaptations that help them sprint up to 30 mph through wooded terrain and jump 10 feet high and 30 feet wide in one bound. This means, while predators may have to run around large obstacles such as fallen trees, the deer are able to leap over them and escape. White-tailed deer are also good swimmers and sometimes enter lakes to make their getaway. Not all adaptations are designed for flight. White-tailed deer have sharp hooves and the front ones are longer than the back ones. They can rear up and use their front hooves as weapons, killing coyotes or wolves with a blow.
Warning Signals and Other Messages
When white-tailed deer sense danger and flee, they wag their tails and lift them to expose the white undersides as a warning to others. Deer also can pick up warning scents secreted from glands in the hooves. The secretions from these glands communicate other information between white-tailed deer and are very strong during the mating season.
Winter Survival Tactics
In summer, white-tailed deer have reddish-brown coats, which they shed for grayish-brown ones in the winter. Their winter coats are well insulated, with dense under fur; the longer guard hairs have hollow shafts. During the fall, the deer also store extra body fat around their organs and under their skin. This provides insulation and energy reserves. Behavioral adaptations are important for winter survival too. White-tailed deer form larger groups and move to more sheltered areas known as deer yards, where stands of fir, cedar and spruce, create good cover. The trees' canopies help to intercept the snow and reduce its depth. While larger numbers of deer are able to share the energy costs required to keep open trails that provide access to cover, food and escape routes.
- National Geographic: White-Tailed Deer Odocoileus Virginianus
- Animal Diversity Web: Odocoileus Virginianus White-Tailed Deer
- Maryland Department of Natural Resources: Before "Rescuing" That White-Tailed Fawn.... Think Twice!
- National Park Service U.S. Department of the Interior Valley Forge National Historical Park: White-Tailed Deer: Adapted for Survival
- Maine Department of Inland Fisheries and Wildlife: Living On the Edge How Deer Survive Winter
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