Where did Whitney dissappear to in "The Most Dangerous Game"? What happened to him?

Whitney is a minor character in “The Most Dangerous Game.” He is only mentioned at the beginning of the story to create the exposition. Whitney is on the yacht with Rainsford, and after Rainsford and Whitney have a discussion on the ethics of hunting, Whitney goes below deck to sleep for the night. When Rainsford falls into the water after hearing the gun shots, the yacht keeps going, taking Whitney with it. Whitney’s role in the story is important, however, because his discussion with Rainsford foreshadows the events to come. He gives the reader important information about Death-Trap Island, telling Rainsford that "The place has a reputation--a bad one."