Clarence was a wild born Velociraptor on Isla Nublar that Lex Murphy named after it attacked Dr. Alan Grant. Grant tranquilized ‘Clarence’ and placed him a cage to take back to the Visitors’ Center to show the others that the dinosaurs were breeding. Clarence had made his home in the service tunnel that was behind a man-made waterfall. Later, Lex outfitted Clarence with a radio collar. While placing the collar on, it was observed that the color of Clarence’s skin changed in accordance to his mood; becoming lighter green when he was agitated, and reverting to a paler state when he was more relaxed. This was apparently a trait unique to the wild born Velociraptors, as opposed to the genetically created ones.
The juvenile raptor then made his way back to the nest, tracked by Ellie Sattler, Robert Muldoon, Donald Gennaro, and Grant with the use of a radio tracking headset. When Ellie, Gennaro, and Grant were exploring the nest, hidden behind steel junction boxes, Clarence approached Ellie. The radio collar was still around his neck, and it was chafing against his skin. Ellie then removed the collar and placed it on the ground. Clarence, irritation removed, squeaked and scampered off to join his friends.