Where’s the food?

Looking at the winter landscape now makes me wonder how and where the deer find enough food to sustain them over the winter.  Pretty bleak-looking, isn’t it?

winter landscape

It’s not only cold (which drives up energy costs), but the most unproductive (vegetatively speaking) time of year to be an herbivore.  Do stumps, trunks, and twigs, along with scraggly raspberry vines and wildflower seed heads have any nutrition in them?  How do the deer manage?

winter deer

Deer are selective browsers, not grazers, which means that they sample twigs, leaves, buds, fruit, berries, nuts, etc. but are not the mowing machines that cattle or horse are in a pasture.  A mouthful here, a mouthful there, pulling and ripping the tops off vegetation because they have no opposing incisors with which to bite cleanly.

Small buck feeding as he walked along.  I could see him chewing when he raised his head.

Small buck feeding as he walked along.  I could see him chewing when he raised his head.

There’s not much nutrition in a twig, but there might be in a bud — the plant’s storage site for rapid regrowth in the spring.  That’s why I “cage” my azaleas in the winter, after watching deer consume the flower buds for several years.

I placed chicken wire cages around the azaleas in the fall.

I placed chicken wire cages around the azaleas in the fall.

Deer love nuts, especially acorns, which are full of carbohydrate.  In the fall, deer preferentially select white oak acorns which are sweeter and contain less tannins, so they can store as much body fat as possible to last them over the winter.

White acorns (left) are smoother and more oblong than red acorns (right).

White oak acorns (left) are smoother and more oblong than red oak acorns (right).  Photo from http://www.sweetpeachblog.com/journal/tag/red-oak

But acorns are buried under a foot of snow in my backyard, so what else is there to eat?  Twigs of dogwood, willow, sassafras, honeysuckle, and blueberry are favorite deer browse in the winter, as well as the growing tips of red cedar, and seed heads of sumac.  A logging operation that left pine tree tops on the ground attracted a large deer herd in Maine (see photo below).

A logical (though unexpected) adaptation to the sparse resources of the winter might be reduction in food intake.  Even though cold winter temperatures mean higher energy expenditures to keep warm, deer do reduce their food intake in winter, relying on fat reserves for up to 40% of their daily energy requirements.

Young of the year are especially vulnerable to low food supplies in the winter.

Young of the year are especially vulnerable to low food supplies in the winter.

That means fall feeding is most critical to insure winter survival, and the fall nut and seed crop is key to putting on the fat.  What they can’t find in nature at that time, they can often find in our backyards, under the bird feeders.  Twice, deer have pulled bird feeders right off the post and scarfed down the contents.  I’ve learned to hang the feeders out of their reach.

10 thoughts on “Where’s the food?

  1. It ain’t easy, bein’ a deer! They are good at finding whatever there is, though, and somehow making it work. Down here, they eat ornamentals, citrus, and pretty much everything else they can. My friend who has country acreage says they come up onto his front porch and eat his potted impatience! And his small citrus trees don’t have a prayer. They are eaten to the nub before they can get any growth going at all, unless he cages them, like you do your azaleas. Oh, yeah. They eat his azaleas, too! Makes my marauding squirrels look pretty harmless, in comparison.

    I don’t blame the deer though. A deer’s gotta do what a deer’s gotta do. After all, it’s a man eat deer world out there, and any trick to help them survive is a good one. Beautiful photos and interesting information. I didn’t know that about the logging providing them a bonus buffet. Thanks, Sue!

    • You’re so right. Deer adapt to the pressures we, and the environment, put on them. No deer in urban Florida? Are they only found out in the countryside?

      • Well, “urban” meaning the city of Orlando, and actual “town” areas, not so much. Way too much traffic and not enough green. But in the suburbs, certainly, if the division is built near a green area or park or protected river. But there wouldn’t be any in my neighborhood, for sure. However, having said that, if I drive about 5 miles down the road, away from the mall and towards the river, which is a preserve, there are a kajillion of them. They just don’t come into the truly urban areas. Just too much traffic and people, I think.

    • It seems they all have a different bag of tricks to use when times get tough. That’s what I find so fascinating about animal adaptations. I would be equally fascinated about plant strategies if I knew anything about them….

  2. Most of nature’s creatures are amazingly creative and resourceful when it comes to surviving the winter. I learned a lot from your post. I’ve always wondered if feeding deer pellets is a good idea. We don’t do it on our farm because there is so much browse material and acorns for them to eat, but that question has always been on my mind. What do your think?

    • Jo Ann, you bring up a good point about whether to feed deer in the winter or not. The information I read on deer winter physiology encouraged no feeding. Why? Because the microbial flora of the gut changes from season to season, and the winter flora apparently cannot digest the same sorts of food that the summer flora can, e.g., the compacted, dense nutrients of a deer pellet. So…the best advice is to let them fatten up on acorns and other foods in the fall and coast on their fat reserves and what woody vegetation they can find in the winter. Thanks for writing and asking a good question!

  3. Pingback: Where have you been lately? | Back Yard Biology

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