Deer are gentle creatures that you may be lucky enough to catch a glimpse of before they run off. Because deer are so skittish it can be difficult to tell how old they are. So you’re probably wondering how long do deer live?
The average life expectancy of a wild deer is 3-12 years old. White-tail deer have the shortest life span on average around 2-3 years old. Most wild deer will die within their first year of life. The lifespan of a deer is affected by the species, health, predators, habitat, and human activity.
You may be curious as to how long the local deer in your area will survive. This guide will take you through all you need to know about what impacts a deer’s lifespan. You’ll also find advice about how to live alongside deer and how to minimize your impact on them.
Let’s jump in.
How long do Deer live in the wild?
The age a deer will naturally live to will depend on each subspecies. Some deer can live up to 25 years in the wild, yet most won’t.
Take a look at the average age of each wild deer species.
|Deer Species||Life Expectancy|
|White-tailed deer||2-6 years|
|Black-Tailed Deer||3-7 years|
|Mule deer||9-11 years|
|Red Deer||10-12 years|
You’ll see that there is quite a large age range between the survival rates of some species.
The reason that some deer live longer than others is the conditions in which the deer lives. Some deer can live in ideal conditions and have a better chance at survival than others. Other deer have lifestyle factors that make them more vulnerable in the wild.
The reality is that most wild deer will die in infancy. In fact, it’s been estimated that between 30-60% of baby deer won’t survive their first year of life. As with most wild animals young deer are much more vulnerable to disease, predators, and starvation than adults.
Larger deer seem to live longer than smaller deer species. Yet larger males die on average 2 years before females. So it’s more likely the large deer survive longer due to life factors rather than their actual size.
Let’s take a look at the factors that affect the age a deer will survive to.
1. Food Sources
Food availability is one of the major threats to a wild deer’s survival. Deer are large mammals and they need a steady supply of food to meet their energy requirements each day. This will increase at certain times of the year such as mating and breeding season.
A deer diet consists mainly of plant vegetation. Depending on the species of deer they will adapt their diet to eat what is available seasonally. This adaptation between different types of vegetation helps them to survive through each season.
The main season of concern is winter when fresh vegetation is in short supply. To combat this some deer species will try to eat more in the warmer seasons. This creates emergency fat supplies to help them survive the days when they have no food.
Species such as moose mostly live in cold climates with little fresh vegetation. They have adapted to this by eating a diet of mainly twigs and aquatic plants.
Harsh winter weather means that thick snowfall can make it hard for deer to source food. They’ll often waste energy walking in snow or the temperatures are too low to browse.
Lack of food often leads to deer starving in the winter period. Starvation accounts for around 10% of deer deaths every year. Young deer going through their first winter are usually the first victims of winter starvation.
Some deer species have adapted by turning to easy food sources supplied by humans. This includes birdseed in feeders or crops from farmlands. Sadly overreliance on these foods can cause nutritional deficiencies and ill health. This can make the deer more vulnerable in the wild.
Deer can be prey for a few larger wildlife predators who will kill them to eat.
Common deer predators include:
- Mountain lions
Predators make up around 12% of deer deaths every year. Wolves and coyotes are the main wildlife predators of all deer species.
Most of these deaths will be from deer that are young, old, injured, and diseased. These traits make them more vulnerable, slower and easily disorientated. Mother deer may try to stay away from their fawns so as not to attract predators to them.
Although wildlife predators cause a lot of deer deaths each year, it pales in comparison to how many deer are killed by human hunting. In fact, hunters kill around 6 million deer in the USA every year. The deer are killed for sport, food, fur, and pest status.
The health of a deer will have a big impact on how long it will be able to survive. Disease and parasites are amongst the biggest killers for wild deer.
Common diseases that affect wild deer are:
- Chronic Wasting disease (CWD)
- Hemorrhagic disease (HD)
- Bovine Tuberculosis
These are just a few of the most common diseases that most deer species are vulnerable to. Outbreaks of diseases such as CWD are highly contagious and can kill deer in large numbers.
These diseases can kill the deer alone. But, they can also cause confusion which makes the deer vulnerable to predators. Infected deer can also become too weak or disorientated to find food and water supplies. This can lead to them dying from dehydration and starvation. In the wild, deer don’t have access to medical treatment which would help them to survive.
The habitat that deer live in can make them much more vulnerable to injuries. A severe injury is a risk to the deer life as they may not be able to flee from predators, find food or they can contract an infection.
Deer that live nearer to urban areas are at the greatest risk of injury. The most common injury to deer is vehicle collisions. It’s estimated there are around 1 million deer collisions in the USA each year. If the deer don’t die they will likely sustain significant injuries from internal trauma, broken bones, or large open wounds.
Other human-related injuries caused to deer are often a result of hunting or people trying to keep deer off their land. Common injuries that result from this are gunshot wounds, dog bites, poisoning, or trap wounds.
Deer can also sustain injuries when trying to escape from predators who have sharp teeth and claws. Another common cause of deer injuries is the fighting behaviors of rutting bucks. Their sharp horns can often cause deer to lose eyes or sustain large infected wounds.
Deer species can be found in various climates all over the world. Some species are more accustomed to living in cold conditions and others in hot conditions. But most deer species live in temperate climates. Deer don’t hibernate in winter, so they often need to make adaptations to survive the change in season from summer to winter.
Cold winter conditions are particularly tricky for deer. Low temperatures can result in them suffering from hypothermia if they can’t find appropriate shelter or fall into icy waters. Most deer species make special adaptations by growing a winter coat and staying together in herds for body heat.
If a deer hasn’t stored enough fat during the warm seasons then they may become malnourished and vulnerable during the winter months.
Some species, such as the moose, are better adapted to live in cold weather. Moose struggle in warmer weather conditions. They can die easily from heat stress if they can’t cool down quickly in hot weather.
How to help Deer live longer in the wild
For their size deer have a surprisingly short lifespan in the wild. This is partially due to their environment but a large part due to human influences. There are a few ways in which you can reduce your impact on the local deer.
Let’s look a 5 ways you can help wild deer to live longer.
1. Prevent Injury
There is little you can do about deer sustaining an injury in the wild. However, since a lot of deer are killed by road traffic accidents each year, this is the best place to start.
The main thing to keep in mind is to be vigilant especially in areas with low visibility at the roadside. Deer are often on the move in herds in fall and spring, usually at dawn and dusk, so be extra wary at these times.
Using your high beam and horn is usually enough to scare off a deer that is in the middle of the roadway. And finally, to keep yourself as safe as possible try to stick to the speed limit, especially if there are deer warning signs on the roadside.
2. Don’t Feed them
This may seem like a weird way to help deer survive. Surely feeding them would help them not to starve? But you shouldn’t purposely put food out for deer to eat in your yard. Not only can it harm the deer but it’s probably best to mention that feeding deer is also illegal in a lot of states.
The problem is that once the deer realize you have an easy food source they’ll keep coming back again and again. Eating too much food that is not naturally occurring can result in ill health from nutritional deficiencies.
Attracting deer into urban areas also puts them at risk. This can be from road collisions, dog attacks, or people using dangerous methods to deter them from their yards.
3. Deter Humanely
Seeing deer can be a nice surprise if you like to watch the wildlife in your yard. Yet they can be quite destructive and cause a lot of damage to your landscaping. Once they’re done they’ll move off to your neighbor’s yard, which probably won’t go down well!
There are a few ways you can deter deer from your yard without harming them. Check out my guide on 14 easy ways to keep deer out of your yard.
Shooting or trapping deer is not the answer in this situation. You may have dealt with one deer but your yard remains attractive to them. If you don’t sort that out more will come along. Making your yard less appealing to the deer is the best way to deal with this issue.
4. Don’t relocate
Trapping and relocating deer is cruel and likely to result in death for the deer. That’s because the deer will be stressed and disorientated by the unfamiliar landscape they are released into. They’ll find it difficult to find food and water. Plus they’re more vulnerable to unfamiliar predators in the new area.
Relocated deer may stumble on the territory of a more aggressive deer who will want to fight them. A female deer may also be relocated away from a fawn who will starve or succumb to predators without its mother nearby.
5. Find a rehabber
If you find a sick, injured, or potentially orphaned deer then you should seek advice from a wildlife rehabber.
These services are specialists in dealing with wildlife. The best way is to inform them where the animal is. Don’t try to capture or approach the animal as you’ll put yourself and the deer at risk of injury or stress.
To find a wildlife rehabilitator in your area check out this resource from the humane society.
How long do deer live in captivity?
Deer can live in captivity for 15-20 years. This is a lot longer than deer in the wild as they don’t need to deal with a lot of the same issues that wild deer do. Captive deer also have access to health care when they become unwell, which improves their chances of survival.
Captive deer are protected from predators, succumb to fewer injuries, and have a steady, nutritious food supply. Due to these factors, captive deer will mostly die from old age rather than poor health or prey for other wild animals.
Wild deer will live for around 3-12 years depending on the species. If they live in ideal conditions then they are likely to survive a lot longer than this. The first year of life is a crucial time when most deer will die.
Once the deer reach adulthood they lifespan will depend on a few factors including food sources, predators, habitat, and health.
Humans have the biggest impact on deer survival, from hunting and road collisions killing 7 million deer each year. Consider what steps you can take to reduce your impact on the local deer population.