Over the next two months all over New England whitetail does will be giving birth to their fawns. Although it is still late winter and we could have some very cold weather for the next month, impregnated does are already starting to drop their young. You would think it would be too cold and that the young would freeze in this weather, but , in fact, these fawns are very tough little folks.
The breeding season in the fall is the beginning of the life cycle of the white-tailed deer. In our area the rut usually occurs from late October through early December. The length of the rut is generally determined by latitude and the length of the day. In the northern states with the shorter days of Fall, the rutting activity increases and ends within a relatively short period of time. In the southern states differences in the length of the days are not as pronounced and the breeding activity lasts for a longer period of time.
The heat or estrus period in the doe lasts about 24 hours. If the doe is not bred during this time period, she will come into heat again in about a month. A doe that has not bred is capable of coming into heat about 5 times during the year. The gestation period of the typical white-tailed deer is about 6.5 months which means that most of the young born in this area will drop during the last of March and the month of April. If a doe is giving birth for the first time she will usually have 1 fawn. Older does usually give birth to twins and when conditions are really good, triplets.
When the doe fawn breeds is usually dependent on their physical condition. Large doe fawns can breed as early as 6 months old. In a wonderfully detailed four-year study conducted in Pennsylvania, these tendencies have been tracked extensively. Launched in 2000, the inquiry aimed to answer questions about pregnancy rates, the peak and the range of the rut, when fawns are born and the number of young carried per doe. The researchers collected data from 3,180 road-killed deer. The work involved determining the date the deer died and measuring embryos found within the deer. While it wasn’t pleasant work for those gathering the data, results showed, for example, during the months a doe should be pregnant 91 percent of the adult does and 26 percent of the fawns statewide were carrying young.