Stuck in the rut — 8 facts about whitetail deer rut

You've probably heard of the rut.

And if you're a deer hunter, then you most definitely have. However, there may be some facts about rut that you're not overly familiar with.

deer with rack

  1. Rut is a word for deer breeding season, not just the peak. It actually means all behaviors and activities associated with breeding season and can be broken into different phases.
    1. Pre-rut: Does have not come into estrus --- breeding cycle --- but they begin to move into family groups. Bucks form bachelor groups and co-mingle with does around food. (Sounds like dating, right?)
    2. Early rut: Testosterone levels rise in bucks and does enter estrus. This is a time when buck activity increases and becomes more reckless. Drivers beware as bucks move across roads without caution at this period.
    3. Full rut: The majority of does are in estrus, and bucks will move farther and farther from their home turf to find does.
    4. Post rut: Most breeding is over, and bucks are not as visible to people.
    5. Second rut: About 26-28 days after the first full rut, remaining unbred does come into estrus for a second time. It is a short period but offers one more chance at breeding.
    6. Late season: Rut is over, and bucks seek refuge in areas of cover. Deer activity revolves around feeding instead of breeding.
  2. Some categorize rut into three phases instead --- seeking, chasing and tending.
  3. Rut doesn't begin because of temperatures but because of photoperiod, or daylight length. Deer are short-day breeders, so dwindling daylight signals to them it is breeding season.
  4. The first signs of rut are sparring. As testerone levels in bucks rise, they will begin to spar or fight. They may look like a shoving match early in rut, or they may look like a serious antler grudge match the closer to full rut they get. Learn more about the rut at https://youtu.be/rD4tPPSBuiQ
  5. Rubbing is not just to get rid of velvet. Buck antlers start out with a fuzzy velvet coating that is lost as testerone levels rise and daylight decreases. It may seem like they begin to rub trees to help their velvet come off, but rubbing truly is a way to spread scent, and some scientists think it also allows deer to visually communicate. Rubbing continues through the rut and is usually made by a buck rubbing his antlers or forehead on a tree.
    Deer may also chew or lick branches to spread scent.
  6. Scrapes are different from rubs. Bucks will paw a piece of ground to bare soil and will urinate in the spot.
  7. Deer can perceive a variety of communicative scents. Urine, vaginal secretions, skin gland secretions, saliva --- deer can sense a lot about each other through scent.
    Bucks can perceive chemical signals in doe urine through the nose but also through the vomeronasal organ. You might have heard of the Jacobson's organ in snakes (see a video about it here), and the vomeronasal organ is the same thing. Basically, there is a small opening near the center of the roof of a deer's mouth. Bucks will taste a doe's urine, closes his nostrils and flicks the scent of the urine into his vomeronasal organ. This organ then sends the chemical signals to the hypothalamus --- the part of the brain that controls reproduction.
  8. Does breed once they reach a certain weight. You might think it's age, but does usually breed when they reach 70-80 pounds instead. doe in front of fence in snow
  9. Does can breed with multiple bucks. If a receptive doe breeds with a buck that is the run off by a more dominant buck while she is still receptive, she can breed multiple times.

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