How Long Do Deer Live?

Whitetail and mule deer are North America's inhabitants, and scientist says they were more than 45 million in number before Europeans invaded North America. The lifespan of a whitetail is equated to be 4.5 years as there are no track records to prove this apart from the fossils remains after the death of a deer.

Just like humans, male deer have a shorter lifespan of 2.5 years compared to the female which has a lifespan of  6.5 years.

Breeding usually takes place towards the end of August and gestation will last for 190 to 210 days, and this ensures the spawn has a chance of survival as it will be born when there is enough food to feed.

Why is deer lifespan shorter in the wild? Here are factors causing the sudden death:

Hunting

Even though there are laws and regulations governing deer hunting in North America, it has helped very little to prevent the early deaths of deer. It is a requirement for hunters to have licenses from relevant authorities which permits hunting for a specified period of time. Hunting deer has not reduced their number as they increase at a high rate compared to previous years.

Predation

Coyote, bobcat, and bears are the most common predators of deer.  During the winter season, there is no vegetation cover to hide, and this makes them visible to predators. Deer are weak during the winter season making them an easy target for predators.

It is very rare to get a fawn during winter, and the older deer are the ones vulnerable to predation. The older deer are weaker compared to the younger ones as they are not able to store enough fat that will last them through the winter season.

The fawns are born during the late spring and early summer season making them target for the predators as they are weak and not able to run as first as the older deer.

Diseases

There are a number of diseases which affects the deer. These diseases have no effect on the number as their digits continue to grow. The hemorrhagic disease is characterized by a high fever that makes the deer to sleep in water bodies so as to reduce the body temperature. In most cases, the infected deer are found dead beside water bodies. They lose appetite, become weak and unconscious. After 8-36 hours of the symptomatic stage of the disease, the animal goes into shock and eventually dies.

Bluetongue virus is another disease affecting deer as it is characterized by fever, swollen lymph, drooling, hooves become fragile and deformed.  When the hooves are deformed, they become painful, and as a result, it becomes hard for the deer to search for food, and it eventually dies of starvation.

Parasitic worms are not that fatal, but they can in some cases damage the lungs making it susceptible to Pneumonia. They also multiply in the stomach preventing the deer from eating enough pasture causing emaciation and eventually death.

Fighting

Male deer usually fight for territory or a female in heat. They get injured during the fights, and the sores get infected by bacteria which leads to brain abscess and sudden death. When the bacteria is inside the deer's head, it causes blindness, preventing it from feeding properly and the deer become weak and eventually dies.

Changing Weather

Deer are omnivorous animals that feed on vegetation, and unlike cows and goats that can feed on any type of grass, they only feed on young and soft vegetation. It is because of this fact that they suffer from starvation which might lead to death as there is no vegetation during winter and early spring.

Their body is made to prepare for the winter season by storing fat under the skin that will last them for 90 days and during these 90 days, they will be feeding on tree buds which sometimes can be hard to reach.

Amid the end of winter season in March, the deer will have used up all the stored fat in the body living it to survive on tree buds. Some deer are not able to make it especially the older ones because they lost the ability to store enough fat like the younger ones living them exposed to starvation and eventual death.

Accidents

Before the development of roads and infrastructure, there were no vehicle-deer collisions. When their habitats were invaded, the accidents between vehicle and them became more and more apparent. The number of these accidents are not the same throughout the year as it is higher during the mating season.

The life expectancy rate of a deer in captive is much higher than the wild deer. It is because they are protected and taken care of properly. Deer can live up to 6-14 years in captivity. It is clear how protected the deer is from diseases, hunting, accident, and predation. Despite the males being protected in captivity, it still has the lower lifespan compared to that of female deer. Maybe it is the way nature dictates just like humans.

Even with possible threats to the deer's lifespan in the wild, it is not likely for their numbers to decrease. As you have read at the beginning of this article the cause of death in deer is periodic throughout the year but it is unclear how these wild animals continue to increase in number than the previous years, yet there are many things working to their own disadvantage.

It is obvious there are more fawns born each year compensating for the loss of the ones killed by diseases, road carnage or predators. The female is able to give birth to more than one fawn making it favorable for the number to increase. The lifespan of a deer is calculated by counting rings on the teeth, formed as a result of feeding but this is possible when the deer is already dead because how would you be able to observe and count the rings?