How Big Can House Mice Get?

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One of the most populous species of pest animals to be found in many parts of the United States is the mouse, and there are a large number of different varieties of mice that are to be found, which is why different species will grow to different sizes. There are also plenty of other factors that can also have an impact on how large the mice will grow, including the food sources that they have access to and the range of predators and factors affecting the mortality of the animals. Mice can be a real problem for the people that live in properties where they are present, so correctly identifying that mice are present can really help people to deal with the problem.



The Growth Of Young Mice

Although they are much smaller than rats, mice are another similar species of rodent that doesn't have a particular mating season, rather mice will tend to have a higher mortality rates when conditions aren't as conducive for raising baby mice. When born they will weigh just a fraction of an ounce, and even when weaned they weigh less than half an ounce in most cases, although these weights vary with species. The mice also grow to adulthood and sexual maturity very quickly too, with the majority of mice actually starting to become sexually mature in less than two months after birth, which is one reason why populations can grow quickly when the conditions are right.

The Largest Species Of Mouse

The majority of the mice that you will find in the United States will be relatively small creatures, especially when compared with their larger rodent cousin, the rat. These mice generally weigh between one and two ounces, and are up to three inches in length. The key thing to note is that although they are quite small creatures, mice will often have a tail that can be several times the length of the body. Among the most common species that you will find in this country are the deer mouse and the house mouse.

However, when you look at mouse species around the world, there are several large species, and one found in Asia is the Large Mindoro Forest Mouse, which can grow up to twice the weight of normal mice, and up to five inches in length. However, the largest mice in the world are believed to be found on a small island known as Gough Island in the South Atlantic, where the mice prey on young birds and eggs in this small corner of the world.

Mice In Captivity

Mice in captivity usually have a similar life span to their cousins in the wild, but there are often factors here that can lead to the animals growing to be larger than mice in the wild. As pet mice will tend to be better fed and be less active than wild mice in general, those in captivity can grow to be larger and in some cases overweight.

Conditions That Allow Mice To Thrive

Although the presence of good food sources is one of the most important reasons why a mouse population can grow, and lead to larger mice, there are also other factors to consider too. Areas which have fewer predators such as feral or domesticated cats, and areas where there are few other factors that can increase mortality rates will also see mice living for longer and growing larger. These are both factors that mean mice can thrive in domestic properties, as in many homes there will be no predators and plenty of different food sources that the mice can get into, which can be a real problem for home owners.

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