O'Roarke is an obnoxious, raspy-voiced bull who tricks Baloo and Wildcat into taking him to a mysterious land of dinosaurs that come alive with the aid of a magical waterfall, presumably to start a touring business in the episode "Paradise Lost". However, his real motives are considerably darker than what he leads the others to believe (he wants to start a hunting-guide business for big-game hunters who want to kill dinosaurs). In order to foil his plans, Wildcat shuts off the waterfall so as to hide the valley from the hunters, but due to the mechanic's good nature and feelings of wonder toward the prehistoric creatures, he secretly allows the waterfall to later reopen which allows the dinosaurs to live again in peace.
He is a large, obese cattle with black hair and mustache. He wears a white jacket and pants, a brown-shirt, a safari-themed hat or pith helmet and carries a brown bag. He's also shown to be quite buff.