Deer are some of the most important wild animals that exist in our world today.
They are a keystone species that many creatures across the globe rely on as a food source to hunt and plants rely on them as their feces add nutrients back to the soil, helping them grow.
Even humans rely on them somewhat, with many different cultures and groups hunting deer for their meat and leather.
If you went to a supermarket today, there is a good chance you’d find some venison to eat, even if it is expensive.
However, for all their import and diversity, they are elusive and wary animals. They hide in wooded areas and only appear when they believe it is safe to graze, before slinking back into the trees.
This mystery has stumped a lot of people when discussing their feeding habits. We know what other herbivores eat, cows and horses eat grasses, giraffes browse on leaves, but what do deer eat?
Are they grass eaters too? Or is their diet a bit more diverse? Today, we will look at deer more closely and determine what exactly these mysterious woodland beings enjoy for a lunchtime snack.
Seasonal Beasts
The diet of a deer is surprisingly diverse and varied, especially when you compare them to other herbivores, who tend to eat things that are similar to one another. This is because of the vast environments that deer live in.
Whereas other creatures have adapted to one particular set of conditions, like a horse is a grass feeding plains dwelling animal, deer live all over and on almost every continent excluding Australia and Antarctica.
These areas are vast and varied in size, resources, and weather, and so deer have had to adapt to each environment in order to survive.
From the cold taiga of Siberia to the humid forests of southern China, deer have thrived, and this adaptation comes from the deer’s willingness to change its eating habits depending on the season.
The availability of certain foods will be limited based on the weather and season, and so deer have learned to look for different foods instead.
Deer will change their diet to suit the environment, however they have four favorite types of food that they keep an eye out for at different points of the year.
These are forbs, browse, grass, and mast (hard mast and soft mast). With these four foods in mind, we will now take a look at each season’s banquet that a deer can look forward to.
Spring
Spring is the season of bountiful food, especially after a long hard winter. Food is particularly important at this time of year, not just as a recovery food, but because doe’s will give birth to fawns and stags will need to grow antlers for the fall rut.
Both of these activities require huge amounts of nutrients in order to complete them successfully, and so this is a time when deer will be the most proactive in their hunt for food.
At this time of year, a lot of food is on offer, with fruits, forbs, buds, and grass being the primary items on a deer’s menu during this season. Forbs are broadleaf flowering plants, frequently ones we considered weeds.
So, these would plant like dandelions, bracken ferns, ragweed, and so on.
Spring is normally the time of year when deer will gorge themselves and be slightly pickier about what they eat, simply because there is more on offer, choosing young buds over old bracken.
Summer
Deer will begin changing what they eat in summer, as the selection will change from certain fruits and buds to berries and greens.
Summer has the most varied selection of food for deer, as flowers are still in bloom but the trees and plants have regained their leaves and foliage, not only that but this is the time of year when berries come into season, which deer love to eat.
Towards the end of summer, there may be some early autumnal foods that deer can feast on as well, like early apples or acorns.
However, this type of food is not particularly common in summer and tends to make up only 11% of the deer’s diet through this season, with most of the food they eat at this time being either leafy foliage or grasses.
Fall
There are a few important events in fall for deer that mean they focus heavily on feeding.
The first is the rut, the annual mating season of deer in which stags compete to establish a territory and to attract mates, and the second is the approaching winter months.
Deer begin fattening up on the bounties available in summer, but it is really in autumn that it goes into full swing. In fall, a deer’s diet is up to 30% mast, compared to below 15% for every other season in the year.
Mast is the fruit of forest trees and shrubs, with hard mast being things like acorns and nuts, and soft mast being berries and other soft fruits.
Deer aim to eat a lot of hard mast throughout this season, as hard mast tends to contain a lot of fat, which the deer will need to survive the cold winter months.
Due to the rut occurring at this time of year as well, deer will try hard to look for food that is heavy in nutrients and calories rather than making do with grasses, as they want to compete in the rut and fatten up at the same time.
If push comes to shove, deer will eat food with fewer nutrients, though it is far from ideal.
Winter
Winter is the most challenging time of year for deer, as it is for most animals. Most of the edible food in the forest has been eaten, stored by other animals, or is now covered by a thick layer of snow.
Deer do not eat much in this season and, in truth, most of the calories they need to survive comes from their own fat reserves, which deer will lose 40% of during this season.
If they are lucky, deer will find some mast or leaves to eat, but other than these rare bounties, most of a deer’s diet will be hard, woody browse.
Browse as food is different parts of a tree or shrub, like leaves, buds, twigs, branches, and even bark, which deer will eat as it is normally the only thing around in winter.
Deer will first eat the leaves and buds in the early winter months and when that runs out they will move on to twigs and branches, before finally stripping the bark from trees during the hardest months of winter.
Browse is not necessarily the most nutrient rich food and to account for this, deer will change their behavior in these months.
They will become less active and slow down their metabolism to use less energy, resulting in them being slow and sluggish.
Sometimes deer will not move at all for a day or so in order to preserve energy and only do so when they need to eat.
This strategy helps them survive winter storms that would otherwise sap them of all their strength.
Final Thoughts
Deer have one of the richest and most varied diets of any herbivore on planet earth today.
Their diet even rival’s omnivores in its variation and by keeping a varied diet, deer have made themselves adaptable to a multitude of different environments, places, and weather conditions.
Their diet is part of the reason deer are so successful, as their willingness to eat almost any plant material has helped them to colonize arctic tundra and scorching deserts with little effort on their part, once they have found a suitable food source.
It is no wonder that they are one of the world’s most successful ruminant families.
