Bob Humphrey is the Biology & Deer Behavior field editor for Buckmasters Whitetail Magazine and holds similar titles with other major hunting publications.
He currently lives in Maine with his wife and two children. For more information about Bob, visit his website at www.bobhumphrey.com.
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Brrr. Catch My Drift?
Cold and extreme cold temperatures affect how well deer detect scents and odors. Watch deer lick their noses to increase humidity and their scents-ability.
QUESTION: While I tend to believe that sound travels better in the cold and allows a deer to hear an intruder/hunter sooner, does extreme cold — less than 32 degrees — affect how well a deer is able to smell and identify attractor scents, human scent or other predatory animals? — Bill B.
ANSWER: Several factors, including temperature, humidity and barometric pressure can influence an animal’s ability to detect odor, and those factors often influence each other.
Moisture traps scent molecules, enhancing the odor they release and slowing down the rate at which they diffuse into air, which is why you sometimes see deer licking their noses when trying to detect trace odors. Cool temperatures also make odor molecules dense and thus easier to detect.
However, in extreme cold the odor molecules may freeze and change from liquid to solid, making them harder to detect, although I do not know at what temperature that occurs.
Extreme cold is often accompanied by drier air, which makes scent molecules even harder to detect. However, it may also coincide with high barometric pressure, which will hold air closer to the ground. Conversely, on warm days, air rises, taking scent with it.