The mating habits of the white-tailed deer (Odocoileus virginianus) vary somewhat depending on habitat. Found in the USA from the Everglades of Florida to Southern parts of Canada, and from the Atlantic seaboard to the Pacific coasts of Washington and Oregon (rarely in Utah, Nevada or California, and not at all in Hawaii or Alaska), the whitetail thrives in both deciduous and coniferous forests, open plains and grasslands, ex-urban and suburban neighborhoods, and mixed agricultural fields. Also, O.virginianus is found throughout Central and South America in many different settings. Old-time scientific nomenclature identified 30 or 40 different sub-species of O. virginianus, but contemporary genetic tests are eliminating some of the distinctions.
The Wisconsin State website on white-tailed deer offers a quick overview. Another useful website is E-Nature. The Integrated Taxonomic Information System will show many links and references for further study. An excellent descriptive source is the US Forest Service fire effects database.
The habitat makes a difference because in some specific settings the “preferred” or most common mating rituals (termed the “rut”) may not be possible or must be modified to suit terrain or vegetation. Two of the most obvious habits of the white-tailed male (buck) are the “rub” and the “scrape.” Bucks have antlers and they use them to scrape up and down on trees to tear the bark and expose raw wood. Then they rub scent glands (on the head and the legs) across the exposed areas to notify other males and the females (does) that a breeding buck is in the area. If there are no trees, as in the desert Southwest or open agricultural fields, the buck uses another mating habit in all areas that signals his rutting presence, the scrape. The buck will paw at and strike the ground to rough up a circular patch of dirt or forest duff or crop residue, etc. The glands between the two parts of the the hooves leave a scent. Then the buck will straddle the scrape and lean to each side in such a way as to urinate down one hind leg, then the other, to mix scent and urine which dribbles onto the roughed up material.
Once a scrape has been scented, other bucks will try to “cover” it and does will leave their own scent marks to indicate that they are in estrous, around the area and ready to mate.
If and when a buck notices another male covering his scrape or marking over a rub on a tree, then the first buck will make specific grunting noises and “rattle” his antlers on trees, shrubs and brush or even the ground as a challenge to the other male(s). Usually the challenge will be accepted and the buck who covered or over-marked will show up for a test of antler size and overall strength. Smaller males, though, will normally make a few gestures and leave, quickly, rather than getting into a surefire lost battle.
Two matched bucks, however, will butt their heads together and use twisting, thrusting, pushing motions until one establishes clear dominance. These matches seldom cause actual injuries to either buck. The losing buck will then move on to other territory and try to set up his own or work other rubs and scrapes, to cover or over-mark and attract females or find a smaller buck that he can dominate.
The females are active participants in the mating process. Does will seek out rubs and scrapes then loiter in the area to be “found” by the dominant buck. The females will leave their own urine and glandular scents to signal the buck that they are sexually in season.
A dominant buck will set up several rubs and a few scrapes then move around among them to increase access to does that are also checking out active sites. Both are opportunistic in these behaviors. The females are in heat for about 24 hours, so the buck must be on the ready throughout the rutting season. Even so, lesser bucks may be able to intervene and mount females in estrous if the larger or more dominant buck is too busy for the number of does available. Similarly, if a buck is in a mating ritual with one doe, other does may move to another area seeking a different male.
This aggressive behavior ensures maximum opportunities for successful impregnation of all the fertile females and maximizes the opportunities for larger, dominant bucks to sire most of the off-spring in a given region each season.
