Bats are quite unusual in comparison to many mammals that you will find. Not only are they the only true flying mammal that there is, but bats have a quality that is more akin to a bird than you would find with a mammal. That is the fact that bats migrate.
At least some of them do. Not every species of bat requires that it migrate. The reason behind that is that many bats live in desert or hot weather areas where it is not necessary for them to leave once the calendar starts to switch towards the wintertime. These particular bats live in the desert areas of the southwestern United States or northern Mexico, or they can be found in areas like Florida, Texas, and Louisiana where the temperature really never gets much colder than 50° for the vast majority of the year. This is a temperature that is not too cold for the bat and so they are able to function quite well year-round here.
That is not the case for every bat, however. There are many bats that live in areas that become cold during the wintertime. When winter comes, they migrate towards states like Arizona or New Mexico, or cross the border into Mexico, and hibernate for the winter. Because they travel in large groups, they are able to protect each other and set up a new colony rather easily for the winter.
There is one group of bats that annually heads towards Minnesota or Wisconsin in the summer time, and when the winter starts to arrive they had back to a location in Kentucky. This has been the generational migration of these bats for thousands of years, but has become endangered because of man-made intervention on their natural resting grounds. Human beings have taken over areas where the bats would normally have migrated to and also have taken measures to try to keep the bats from returning. This is greatly threatening their lifecycle and is leading to colonies decreasing in numbers by the millions. It may not be long before this particular species of bat is gone.
However, for those bats who had to the southwestern portion the United States and then head north during the spring, they are still doing quite well. Most of the areas they returned to in the winter are quite sparse in terms of the number of people who live there. You may only find four or five people living in an area per square acre which means that there is plenty of room in the desert of these areas for the bats to live during the winter.
While not all bats are migratory, there are a group of them, and this is help them to be able to survive and thrive for generations. It can only be hoped that man does not take too many precautions or steps to endanger this migration so that the bat will become a thing of the past. They may be an ugly creature, and maybe even terrifying to some people, but they play an important role in the ecosystem.
Read more: Bat Control