NEW YORK - Regis Philbin may have some competitors for television supremacy: a band of castaways on a rat-infested tropical island.
CBS executives were ecstatic Thursday about the opening night ratings for its high-profile summer reality series, ''Survivor.''
The endurance contest filmed on an island off Borneo managed to hold its own despite ABC's last-minute decision to launch a programming bomb, scheduling an edition of ''Who Wants to Be a Millionaire'' as direct competition.
''Survivor'' drew an audience of 15.5 million people Wednesday, according to Nielsen Media Research. The ''Millionaire'' viewership was 16.8 million, the lowest for an edition of the game show since last November.
More encouraging for CBS was that ''Survivor'' drew a younger audience than any other show on the network's prime-time schedule does regularly, beating ''Millionaire'' by 63 percent among viewers aged 18-34.
Young viewers are prized by advertisers and CBS, whose audience has a median age of over 50, said the ''Survivor'' viewers had a median age of 39.
''It's a new audience for CBS and it's very exciting for us,'' said David Poltrack, CBS's top researcher.
They saw something quite unlike anything that's been on American network TV, even though ''Survivor'' is an adaptation of an idea that's been successful overseas. The 16 castaways are locked in a competition that, by the summer's 13th episode, will result in one winner getting $1 million.
The contestants voted out the first of their colleagues in Wednesday's episode. Sonja Christopher, a 63-year-old musician from Walnut Creek, Calif., who stumbled and fell while carrying a raft in a race, was sent home.
Christopher, who brought a ukelele to the island and has written a song about her experience, said on CBS's ''The Early Show'' that she learned that ''I'm sort of naive.''
''I went there with certain ideas about how we might play this as a team and, sportsmanship was important, having done sports in the past. And I learned that not everybody thinks that way,'' she said.
There will be three contestants left by the final episode this summer. Christopher and others who were voted off the island will return to determine who wins the prize.
CBS, which has already scheduled a rerun of the first ''Survivor'' episode for Saturday night, said it hoped that the audience will build through word of mouth as the series goes on - much like it did for ''Millionaire'' last summer.
One encouraging sign: researchers found the audience for ''Survivor'' grew Wednesday as the hour went on, which meant few people gave up and switched the channel.
ABC said it has no immediate plans to schedule another edition of its game show opposite ''Survivor.'' CBS executives were miffed by ABC's decision to use ''Millionaire'' on Wednesday.