No, Deer Are Not Strict Herbivores. They Eat Birds

When we see deer, they are often grazing for vegetation in meadows and forests. You’ve also probably been told that they only eat plant matter, like grasses and leaves. But surprisingly, deer are not strict herbivores. It may be safe to say that they primarily eat plants. However, researchers have been baffled more than once by their diet. Do deer eat meat, and what happens if they do?

Are Deer Herbivores or Omnivores? And Do They Ever Eat Meat?

Deer are natural herbivores, but they have opportunistic omnivore tendencies. Deer obtain most of their food from plant matter. And specifically, they are known as ruminants, meaning they have multiple compartments in their stomach to help them digest grass and other vegetation without thoroughly chewing it. Other ruminants include cattle, sheep, antelope, and giraffes.

However, deer do eat meat on rare occasions. Researchers have witnessed deer turning carnivorous in the past, eating birds, fish, and dead rabbits. And shockingly, they have also witnessed a white-tailed deer eating rotting human flesh from a forensic site. 

Deer are scavengers that will eat meat and chew on carcasses if the opportunity presents itself.

What Happens if a Deer Eats Meat?

If a deer eats meat, it will be completely fine. It gets most of its nutrients from the plants it consumes. But herbivores like deer can get a good dose of calcium from gnawing on animal bones. Meat makes up a tiny sliver of a deer’s overall diet, which is why it is still classified as an herbivore. Their entire bodies are designed to eat and digest plant material. If they were meant to eat large portions of meat, they would feature adaptations to help them hunt and kill.

Will a Deer Eat a Rabbit?

Deer do not eat rabbits in the traditional sense. They do not hunt and kill rabbits the way a carnivore would. Instead, they will scavenge on a dead rabbit if one comes across their path. They spend their days grazing for vegetation, but they will consume the meat and bones of dead animals if given the opportunity.

Do Deer Eat Squirrels?

Deer eat squirrels the same way they eat rabbits. Deer may consume a dead or injured squirrel if it stumbles upon one while grazing. Again, deer don’t hunt or kill like true meat-eaters. However, they have been known to eat live birds. People have caught deer eating baby birds right from their nests.

Do Deer Eat Bird Seed?

If you own a bird feeder, you already know that deer can be a nuisance. While waiting for your favorite bird to show up, a deer can come by and empty the feeder in just a few minutes. Bird seed may not be a deer’s first choice when it comes to a delicious meal, but they will definitely take advantage if they are hungry. But they tend to avoid bitter-tasting seeds, like nyger and safflower.

Why Do Deer Eat Birds?

Some researchers believe that herbivores occasionally eat meat for no apparent reason, while others speculate they lack certain nutrients in their diet. Deer may eat birds and other animals because they lack calcium, salt, and phosphorous. You may also observe these animals eating more meat products during the winter when plants are hard to find. Some also believe that pregnant and nursing fawns are more likely to consume flesh and bone for extra calcium. Plants don’t contain very much calcium.

Do Deer Eat Birds That Sit on Them?

While this behavior has not been recorded, deer do raid the nests of birds. Deer primarily eat nestlings because they don’t have to work for them. If a deer comes across a nest with baby birds, it will take the opportunity without much hesitation.

Deer and Bird Symbiotic Relationship

Black-billed magpies ride on the backs of deer. But deer do not eat them. These two species have a symbiotic relationship, meaning each receives a benefit from the act. Magpies eat ticks off the deer. The bird gets a free meal and the deer is relieved from these pests. Magpies will also do this for moose and other large mammals.

The photo featured at the top of this post is © Bob Keefer/Shutterstock.com