Many people interested in deer behavior often hear about a “second rut” and wonder if it is a distinct breeding period. This article will clarify what this late-season activity entails, distinguishing it from the primary breeding season and exploring the factors that contribute to its occurrence.
Defining the Late Rut
The “second rut,” more accurately termed the “late rut,” is not a separate, full-blown breeding season. It represents a continuation of reproductive activity in deer populations. It primarily involves does that were not successfully bred during the peak of the primary rut and re-enter estrus, or female fawns that reach sexual maturity later in the season. This period is typically less intense and widespread than the main rut, which sees the majority of breeding activity.
Does are seasonally polyestrous, meaning they can have multiple estrous cycles if they do not conceive during their initial fertile period. If a doe is not bred during her first estrous cycle, she will typically re-enter estrus approximately 28 to 30 days later. This mechanism ensures that most does eventually become pregnant.
Biological Drivers and Timing
The primary reason for the late rut is the re-cycling of does that did not conceive during the peak rut. These does become receptive again about 28 days after their unbred estrous cycle. Additionally, some late-born doe fawns may reach the necessary body weight and maturity to enter their first estrous cycle. This usually occurs when they are around 6 to 8 months old and have attained a body weight of approximately 70-80 pounds.
This late breeding activity generally spans from late December through early January in most regions. This timing is directly influenced by when the primary rut peaks in a given area. For example, if the main rut occurs in mid-November, the late rut would likely follow in mid-December. In some southern regions, breeding activity can extend into February or later.
Several factors influence the prevalence and timing of this late-season activity. Herd health and nutrition play a significant role, as does in good physical condition are more likely to re-cycle or for fawns to reach breeding maturity. Population density can also affect breeding success; in areas with a high doe-to-buck ratio, some does might not be bred during their initial cycle due to fewer available bucks. Environmental conditions, such as mild weather or abundant food sources, can also contribute to a more pronounced late rut by supporting the overall health of the deer population.
Recognizing Late Rut Activity
Observing deer behavior during the late rut reveals specific signs, though often less intense than the peak breeding season. Continued deer movement beyond the primary rut, with bucks actively seeking out does, is a key indicator. While the widespread chasing seen in November might be less common, bucks are still driven to find receptive females.
Bucks may refresh or create new scrapes and rubs, which are visual and scent markers. These signs indicate ongoing buck activity.
The presence of “chasing” behavior, where bucks pursue does, also signals that breeding activity is still underway. This occurs with fewer participants than the main rut.
Implications for Wildlife Observation
Understanding the late rut holds practical relevance for those observing deer. Breeding activity can persist into late December and early January, offering an extended opportunity to observe deer behavior. During this period, bucks, though often fatigued from the primary rut, are still motivated to find the remaining receptive does.
This knowledge can inform observation strategies, guiding individuals to areas where late-cycling does or maturing fawns might attract buck attention. Focusing on traditional deer travel corridors, food sources, and areas with fresh sign can increase the chances of spotting deer movements. Recognizing the subtle signs of the late rut allows for a more informed experience when observing deer.