Each night at Disneyland, after the sunburned and exhausted families and cast members have made their way home, the park fills up again -- this time, with hundreds of cats. The cats are there to help control the mouse population.

They first arrived shortly after Disney opened in 1955 and instead of chasing them away, officials kept them around and put them to work.

These feline friends are well taken care of. When the corporate fat cats are not prowling the grounds, they spend their days hanging out at one of the park's five feeding stations however you may also see them roaming the park during the day.

Disney works to spay and neuter adult cats and any time kittens are found, they're put up for adoption.

The next time you see a cat at Disney -- now you know why.

They even have a twitter page.