When Disneyland opened in 1955, they immediately discovered they had a problem with mice, attracted by all the food dropped on the ground or stored in the various restaurants scattered throughout the theme park. They initially tried poison, but backed off when a child accidentally found a poisoned hot dog on the ground. That’s when Disneyland discovered feral cats roaming the park at night when visitors went home.
During the day, these feral cats hide out of sight, often sleeping in Sleeping Beauty’s castle in the day time. At night, the feral cats roam the park in search of mice.
Disneyland acknowledges the work that these feral cats provide in keeping the park’s mice population down. (All mice except for those wearing costumes like Mickey and Minnie.) In return for their hard work, Disneyland provides food for the feral cats and regular medical checkups to insure they’re healthy. All feral cats on the property get neutered and spayed to keep the population of feral cats to a minimum.