She was found Thursday night near the Foreman Amphitheater a short distance from the zoo.
The bobcat, who is named Grace, is roughly the size of a large housecat, Zoo Director Jamie Huss said. She and her sister Hazel arrived at the zoo in December and have been housed in a habitat designed for bobcats since April.
Zoo officials have not yet figured out how Grace escaped her enclosure; her sister has been moved to another building for safe holding. Bobcats are native to Northwest Indiana.