There are several mammals that hibernate during the winter months to help them survive. If you haven’t seen any deer around during the colder months you’re probably asking yourself ‘do deer hibernate?’
Deer do not hibernate in the winter months. Deer do not have the biological ability to lay dormant for long periods of time. As deer are active during the winter they need to adapt. Some deer will carry out a behavior known as yarding. This includes lowering their metabolism, growing a winter coat, huddling together, and sheltering from the weather.
You may be wondering why deer do yard instead of hibernating. This guide will take you through everything you need to know about what deer do during the winter.
So let’s begin.
Hibernation and Yarding
Before we go on to discuss what deer do during the winter, it’s best to understand what we mean by each behavior.
Can Deer hibernate?
Hibernation is a prolonged period of dormancy for warm-blooded animals. It allows them to drop their temperature, heart rate, breathing, and metabolism. This is the ultimate way to save energy and to survive for long periods without eating when food is scarce.
Mammals such as bats and ground squirrels will hibernate over the winter months.
To hibernate animals need to have the ability to store large amounts of fat, and switch themselves into hibernation mode. These animals have blood with a chemical called Hibernation induction trigger (HIT). This activates hibernation when they recognize the shorter days, falling temperature, and low food supply.
Deer don’t have the physical ability to hibernate, and so they don’t. Deer still need to remain active to source food and eliminates their waste. Yet like all animals, they need to make special adaptations to survive during winter conditions.
What Is Deer Yarding?
Yarding is a specific type of behavior that deer do in the winter. It’s a survival strategy the deer have developed to save energy for a herd of deer. Yarding is mostly done by deer living in northern climates where they encounter snowy conditions.
Deer yarding involves large numbers of deer gathering closely in one area for a prolonged period of time.
Yarding helps deer to:
- Maintain their body heat
- Access good food sources
- Shelter from harsh winter weather
- Protect the herd against predators.
A deer yard will normally be near an east or south-facing slope or tree thicket to provide shelter from the weather.
During yarding, deer will lower their metabolism and move around very little. Normally a period of yarding lasts around one to three months.
What do Deer do in the winter?
All wildlife need to make their own special adaptations to survive the cold winter month. Deer are no different. Deer need to make a lot of preparation before winter to make sure that they make it through.
These adaptations can help them to keep warm, safe, and have enough energy so they don’t starve.
Let’s look at how they go about this.
1. Find Shelter
We’ve already discussed how some deer will ‘yard up’ over the winter months. Usually, this is the behavior of deer living in colder regions.
Yet not all deer will do yarding. In the winter months, deer will find an area of shelter which is much more protected than in other months.
Winter shelter for deer will usually be in a heavily wooded area where the trees and vegetation can provide protection from the snow and keep the cold out. Often deer will shelter in dense bushes or hollowed-out trees.
The place needs to be safe and warm enough for deer to stay for a few days during particularly bad weather conditions. It also needs to protect them from predators but also provide easy access to a food source without too much travel.
Even if deer aren’t yarding they will stick together as a herd for warmth.
2. Diet Adaptation
When the cold months set in deer need to change their diet. That’s because the food that deer like to eat, isn’t widely available in winter.
Deer can still survive by eating vegetation. Yet this will change from soft leafy greens to harder and more fibrous browse such as twigs, pinecones, and bark. Nuts are also a good source of protein and energy during the winter months.
Deer will reduce the amount of food they eat in the winter. It helps that they don’t move around as much to use up energy.
Sheltering near a good food supply means they have only a short distance to travel to eat during winter. This saves energy from foraging during periods of scarce food availability.
Deer can also dig for food with their hoofs. This helps them to adapt to foraging under snow and frozen ground.
3. Fatten up
During the summer months, deer will try to eat as much as possible. Their aim is to add around 25% of their body fat during a time when lots of food is available.
The extra fat not only helps to insulate them in the winter but can be used as an energy source when they are hunkering down or can’t find food.
This fat is stored around their internal organs and under the skin. It’s a strategy for keeping these vital organs healthy during the winter conditions.
4. Grow a coat
A deer’s fur will make physical adaptions to help them survive harsh winter weather.
During the summer and autumn months, deer will shed and grow thicker fur to prepare for winter. This newer coat consists of a dual-layer of soft and warm underfur and a thick and weatherproof top fur known as guard hair.
The extra guard hairs that a deer grows will give them a slightly darker shade to their fur. The dark color allows heat to be trapped by the winter sun and gives the deer extra warmth.
A deer’s winter fur is thicker and longer than their summer coat. This helps to trap in any heat from their body and prevent it from evaporating in the winter air.
Deer will also begin to produce a natural oil from their skin that coats their fur layer. This oil further prevents any heat loss. The oil also prevents any cold or wet coming in from the external conditions and cooling down the deer’s skin.
5. Reduce Activity
A deer’s ability to reduce its daily activity is vital to its survival over the winter months. Winter life is a much slower pace for deer.
When yarding or hunkering down deer will keep their activity very minimal. Most of their time will be spent sleeping or foraging for a short period of time. Often deer will go without food for a few days at a time.
To allow this period of reduced activity deer lower their metabolism to use up less energy. That’s when those essential summer fat stores can be used up.
If a deer needs to travel long periods to forage, flee from predators, or find new places to shelter, they run the risk of using up too much energy.
Depending on how long cold spells last, they may need to brave the harsh weather if their energy supplies are running dangerously low. This can often be fatal for them. Yet deer from a herd will often help each other to forage as much food as they can.
Where do deer go in the winter?
If you’ve not seen many deer around in the winter, don’t worry they are still there.
As the winter conditions bring lower temperatures deer need to reduce their activity to survive. This means they find shelter and stay there for a few days at a time. During this time deer won’t eat and will mainly sleep to conserve energy.
This will happen when there are particularly bad weather spells. Once the weather settles for a few days the deer will come out to forage for short periods of time.
Often you won’t see deer during these hunkering periods as they choose sheltered spots such as thick forest areas for protection.
Do Deer migrate in winter?
Some deer species do migrate during the winter months. Migration is mainly seen in white-tailed and mule deer in northern and western states. Migration deer will usually travel distances of around 8 to 15 miles in search of a good yarding spot with shelter and food sources.
Deer are quite well adapted to survive winter conditions and will survive perfectly fine. That means you won’t find deer migrating for longer distances to find warmer climates in neighboring countries. Yet there is a documented migration of mule deer traveling up to 150 miles for the winter.
All though deer don’t hibernate they will make adaptations to survive over the winter period. These changes help deer to survive through harsh winter conditions and a lack of good food sources.
To do this deer will adapt their diet, grow new fur, find a good place to shelter with their herd, and reduce their activity.
All these together will allow deer to go for long periods without food and protect themselves from winter conditions. Once the weather starts to improve deer can then adjust to warmer weather and abundant food sources.