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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Gut Feeling: Do food-based baits have harmful effects on a whitetail’s digestive system?
QUESTION: What is the effect of commercial attractants (bait) on deer? I’ve heard that sudden changes in a deer’s diet causes the bacteria in their stomach to slowly adjust to the new food and if not continued for a long period can cause problems and even death. — Timothy N.
ANSWER: There is some truth to that. Deer have a very complex digestive system, the foundation of which is their four-chambered stomach, consisting of the rumen, reticulum, omasum and abomasum.
Much of their diet, particularly in the late fall and winter, consists of coarse, woody browse, which is very difficult to digest. It is actually rumen microfauna (bacteria) that digest the coarse fiber (cellulose), converting it into compounds the deer can then absorb. And it takes the deer several weeks to adjust to this poorer diet as the rumen builds up the necessary type and amount of microfauna.
Bait and attractants shouldn’t be a problem unless they are used in times when deer are switching, or have already switched, their diets to woody browse.
Favorable conditions, particularly pH, also are required for proper rumen function. A sudden glut of food like corn could actually harm the bacteria and reduce a deer’s ability to digest other food. Although it’s exceptional, it is possible for a deer to die with a full stomach if that stomach is not functioning properly.
If you provide supplemental feed, it’s important to start early — early to mid fall — and continue feeding until there is sufficient green herbaceous food available in spring. The type of food you supply is important also.
Corn is a quick source of energy but provides little other nutritional value in the winter. Protein blocks are a better option, as they also contain a fair amount of fiber.