Most people are surprised to learn deer grow antlers each year. Even those who are aware of the fact that deer grow and shed antlers each year are often surprised as to why this unique phenomenon occurs.
Though you might not even stumble upon shed deer antlers when hiking, hunting, or taking pictures of mother nature’s beauty during a sightseeing expedition, the truth is deer antlers are likely in your vicinity simply because these beautiful animals shed their antlers each year.
Let’s take a closer look at why deer shed and grow their antlers on an annual basis.
Why Deer Grow and Shed Antlers Each Year
Each year, without exception, deer shed their antlers and grow new antlers. This amazing phenomenon occurs as antlers play an important role in deer reproduction.
Deer rely on their antlers to attract mates. Antlers are also quite insightful as they reveal details about the animal’s age and health. It is particularly interesting to note the condition of deer antlers also plays a role when they are shed.
The animal’s access to nutritional food along with his or her unique health are the primary determinants of the size of the antlers.
The Role of Antlers in Mating
The main reason why deer shed antlers and grow them is for mating purposes. Male deer display their antlers at the first possible opportunity to make it clear they are healthy and ready to mate.
However, male deer also use their antlers to show their dominance. Ideally, this showing of dominance makes it clear the deer is ready and willing to mate, ideally with his choice of female deer. It is particularly interesting to note solely caribou females grow antler racks.
These female deer’s comparably short antlers serve the purpose of fending off other deer as they compete in the search for food for themselves as well as their young throughout the cold winter.
The Growth Rate of Deer Antlers
Most people are surprised to learn even particularly large deer antlers can grow from diminutive nubs into full-size antlers in a period of merely three or four months. This rapid timeline for growth makes deer antlers some of the quickest growing tissues around.
Deer antlers start outgrowing as tiny bony growths along the upper portion of the head, concealed with a small layer of hair and skin referred to as velvet. Velvet serves the purpose of safeguarding the antlers as they grow. These growing antlers are quite fragile as the growth commences.
The Shedding Process
Since deer antlers require an abundance of nutrition and energy to grow, it is in the interest of deer to shed them without delay, ideally immediately after the end of the mating season. Here’s how deer shed their antlers.
The animal’s body draws calcium and other nutrients that ultimately make the antlers weak, fragile, and poised to break. A cell layer grows along the antlers’ base, cutting off the connection to the rest of the body. This process ultimately causes deer to shed their antlers.
It is particularly interesting to note elevated levels of the testosterone hormone mitigates antler growth during the summer months. The arteries and veins by the velvet make it that much more difficult for antlers to grow, cutting off the supply of blood to the antlers.
Once the start of September rolls around, the velvet starts to dry and eventually sheds itself. This process puts the maturing antler’s bone-like structure on display for the fall seasons when deer tend to mate.
Additional Reasons why Deer Grow Antlers Each Year
Deer have evolved to grow antlers on a yearly basis, partially because antlers eventually endure damage. This damage stems from engaging in combat with other deer. Furthermore, everyday living gradually wears down deer antlers.
It is quite possible once the end of the autumn mating seasons ends, deer antler will be considerably blunted or possibly even completely broken off. Deer also shed antlers as a result of testosterone decreasing. When a deer’s testosterone level decreases, it weakens the tissue as well as the bone that supports antlers, leading to the weakening of the antlers and subsequent shedding.
The exact point in time when deer shed their antlers partially depends on factors outside of those detailed above. It is important to note an injured, or wounded deer will shed its antlers sooner than it normally would simply because the injuries prematurely trigger the osteoclasts sooner than would otherwise occur. Osteoclasts are a cell that helps to break apart bone tissue. This process is particularly important for maintaining and repairing bones, including antlers.
Deer who have a declining physical condition are also more likely to shed their antlers before healthy deer. Even deer that do not reside in an area with a mild climate and deer that lack a suitable habitat is likely to shed their antlers sooner than others.
It is quite possible deer living in a relatively mild climate with good surrounding conditions, optimal health, and suitable living space will keep their antlers fully intact into or even beyond the spring months. Deer subjected to the stresses of winter and deer with limited nutrition due to lack of sustenance in their habitat are much more likely to shed their antlers sooner than others.
This is precisely why some late season hunting expeditions ultimately end in a trophy that does not produce any antlers as they were shed days, weeks, or possibly even months earlier.
A Closer Look at the Process of Antler Growth
Protein is the primary cause of deer antler growth. However, minerals also matter a great deal. A process referred to as mobilization occurs, involving the drawing of nutrients from bones within the body to spur antler growth.
The mobilization process involves activating phosphorous and calcium, transferring them to parts of the skeleton such as the bones that comprise the ribs, setting the stage for antlers to be produced. The skeleton is subsequently replenished with nutrients as time progresses, and the animal consumes more food.
In short, this means that deer are capable of growing new antlers on a yearly basis and at a rapid pace as they borrow minerals such as phosphorous and calcium from bones that are non-weight-bearing. This process necessitates considerable energy, even though generating new antlers is not absolutely necessary for survival or reproduction.
In order to replenish the minerals used for antler growth, the deer consume food, including soil. You read that right. Soil plays an important role in the replenishment of minerals that set the stage for additional antler growth.
Soils that have minimal mineral content really do make it much more challenging for the deer to recover. If the quality of the soil is particularly low, supplemental feed might be necessary to maximize the efficiency of mobilization.
The Role of Sunlight in Antler Growth
The amount of sunlight provided during the day plays a large part in determining whether antlers are grown or shed. This period of time for sun exposure is commonly referred to as the photoperiod. For the most part, the greater the amount of sunlight, the more growth will occur.
The alteration in light forces the pineal gland to communicate with the pituitary gland to release that much more testosterone. The bump up in testosterone has the potential to spur antler growth upwards of a couple of inches in a single week.
Do Genetics Play a Role in Antler Shedding and Growth?
In short, yes, genetics matter when it comes to antler shedding and growth. A deer’s antler size and shape is largely determined by the genetics of his parents. However, the environment, including access to resources, also matters a great deal.
Nutrition is particularly important for antler growth following the shedding process. The better the surrounding living space, the larger the antlers will be. Forage that is rich in protein expedites antler growth, allowing for large antlers to emerge that prove that much stronger.
Deer that have access to acorns, partridge peas, beggar’s lice, and/or blackgum have the protein necessary to grow large and beautiful antlers, completing the shedding and growing processes on schedule without exception.
The Timeline of Antler Shedding
The exact amount of time deer holds onto their antlers hinges on a number of factors, including wear and tear, genetics, and nutrition. However, for the most part, deer tend to shed their antlers in December, January, February, and March.
This shedding occurs across a period of two to three weeks. Thankfully, the process of shedding antlers does not cause any pain. Rather, the tissue below the antlers along with the pedicles slowly falls part, allowing the antlers to gradually loosen to the point that they fall off.
By the time spring rolls around, deer have a brand new set of antlers just in time for the mating season a few months later.
Here’s some extra reading – 17 DIFFERENT TYPES OF DEER