As with all living things, the lifespan of a mouse depends on the way its organism functions but also on its environment. Those who appreciate these small rodents would like them to live a long life when those who, on the contrary, hate them hope that their life will be as short as possible. So how long does a mouse live? What is his life expectancy?
What mouse are we talking about?
Mice in the strict sense of the term all belong to the genus Mus. In France, the term “mouse” generally designates the most common species, the Gray Mouse (Mus musculus), also bred as a pet or laboratory animal. But there are many other species of mice in the world, not necessarily well known to Westerners. Here are a few examples:
- The Sumatran Mouse (Mus crociduroides),
- Gairdner’s shrew (Mus pahari),
- Macedonian Mouse (Mus macedonicus),
- The Gleaning Mouse (Mus spicilegus),
- The North African Mouse (Mus spretus),
- The West African Pygmy Mouse (Mus mattheyi).
Each mouse species develops behaviors adapted to its environment in order to ensure the species sustainability. However, to achieve this goal, the best strategy is not necessarily to live as long as possible. Butterflies do this despite a very short lifespan. What about the mouse?
The lifespan of a gray mouse
There is very little literature accessible to specialist names on the species of mice that we have listed above. Among them, it is the most famous gray mouse. But overall, a mouse is a fragile rodent, poorly equipped to deal with its predators. Beyond a few differences, animals of the genus Mus are similar and the orders of magnitude that we give for the Gray Mouse are valid for the whole genus.
A gray mouse lives on average 2 years.
The longevity of two other animals called “mice” but not belonging to the genus Mus is only comparable enough for one of the two: if the white-footed mouse (Peromyscus leucopus) can expect to live as long as a Gray Mouse, i.e. between 12 and 24 months, the deer mouse (Peromyscus maniculatus) has a much shorter life, only between 2 and 14 months.
Obviously, house mice, preserved from the aggressions of the natural environment, will live longer than wild mice. This data is taken into account in the average because the young are very vulnerable and juvenile mortality is high.
If you want a pet that doesn’t take much time, the mouse is perfect for your project. However, children can become attached to the small animal, and such a short lifespan can make them needlessly saddened, unless you consider it a relevant “object lesson”.
The official mouse record the oldest in the world was recorded on April 10, 2004. Her name was Yoda. It was a dwarf male mouse. Born in the University of Michigan medical school, she lived 1,462 days, or Four years. Mice whose genes are manipulated in the lab or used to design cancer drugs may even hope to live longer, up to 5 years.
Why does a mouse live so short?
The life of a Gray Mouse is essentially turned towards reproduction. Sexual maturity occurs between the 28th and 49th day of life. Research has long identified a strong link between early sexual maturity and short lifespan.
Female Gray Mice are in heat every 3 to 6 days, all year round, until around 18 months of age when fertility declines or stops. Males are fertile all their life.
A female can give birth approximately every 50 days. The litters each have 4 to 8 young. This represents the birth of 28 to 60 mice per year per female. In other words, the Gray Mouse is a real “factory” for making babies.
This strategy pays off because no mouse species is endangered, or even threatened. Mouse predators are even essential to preserve the balance ecosystems because it is observed that in areas where they are scarce, mouse populations are exploding. And an overpopulation of mice systematically causes significant damage to the environment.
Take good care of your house mouse
In house mice, mammary tumor is found very often. There is a kind of runaway development of these cells. Rather impressive lumps form to the point of rubbing on the ground and becoming infected. Kidney failure is also common.
If you have decided to adopt a mouse, then you should be prepared to pay the price of surgery if you want to extend the life of your rodent.
The bronchi of this small animal are also very delicate and the choice of a litter suitable, non-harmful or irritant, is essential to limit respiratory diseases.
The quality of the food given to the mouse will also contribute to its longevity: one criterion is to get you as close as possible to the food it can find in the wild. This is not that difficult considering the fact that the mouse is very fond of our grain stocks! But your responsibility will be to balance a little more what a mouse can spontaneously find and to compensate for any nutritional deficiencies that may arise. Hay is the staple food, providing fiber essential to the functioning of its digestive tract. And care must also be taken to limit sugar intake, including through fresh vegetables and fruit.