Nov. 9 (Bloomberg) -- Late-night television ratings fell during the first four days of a Hollywood writers strike as viewers switched away from repeats of ``The Tonight Show With Jay Leno'' and ``Late Night With David Letterman.''

NBC's ``Leno'' had the steepest drop, losing more than 750,000 homes, according to Nielsen Media Research figures supplied by the network. CBS's Letterman lost around 330,000 homes, NBC said today in an e-mail.

``It doesn't bode well, and this is just the start,'' Brad Adgate, head of research at the New York-based ad agency Horizon Media, said in an interview. ``It could be more catastrophic, but there's still a concern of where did these viewers go and will they come back.''

Networks began airing reruns on Nov. 5, when the Writers Guild of America called a strike over payments for the use of TV shows and movies on the Internet and mobile phones. Late-night shows were among the first that went to repeats as the walkout halted production on some programs.

Leno fell to a 3.3 rating from 4 the previous week, and CBS's ``Letterman'' fell to 3.3 from 3.6, according to General Electric Co.'s NBC. Each point equals more than 1 million homes.

CBS data show higher ratings because the broadcaster didn't count Tuesday night due to election coverage, the network said today in an e-mail. Spokesman Chris Ender declined to comment.

Among other late-night shows, ABC's ``Jimmy Kimmel Live!'' fell to 1.6 from 1.8 and NBC's ``Late Night With Conan O'Brien,'' which follows ``Leno,'' dropped to 1.6 from 1.8.

Reruns

Leno's viewership this week compares with a 3.7 rating when the show aired reruns the week of Oct. 22, according to NBC figures. The network shows reruns several times a year when Leno is on vacation.

Putting the talk shows into reruns does more than hurt ratings, Michael Winship, president of the guild's eastern unit, said in an interview today. It also prevents studios from promoting holiday movies by scheduling the actors to appear on the shows, he said.

``That would apply to their advertising, too,'' he said. ``They're reluctant to do an ad buy on a talk show that's in repeats.''

Today the union shut down picket lines to hold a rally near News Corp.'s Twentieth Century Fox movie lot in Los Angeles. The crowd of about 5,000 people forced police to shut down some lanes of Avenue of the Stars and Pico Boulevard in the city's Century City area, Lt. Roger Mora said.

Producers Suspended

The studio suspended producer-writers who refused to cross strikers' picket lines to perform non-writing work on television dramas and comedies.

The company sent suspension notices to so-called multihyphenates, writers who have production deals, advising them they would no longer be paid, Chris Alexander, a spokesman for Los Angeles-based Twentieth Century Fox Television, said today in an interview.

The decision by some producer-writers to stay off the job in support of striking TV and movie writers threatened to shut down work on new episodes where completed scripts were already in hand. The notices were sent Nov. 7, Alexander said.

Two Twentieth Century Fox Television shows, ``Back To You'' and `How I Met Your Mother,'' have stopped production after finishing work on available scripts and 16 are still filming with material that was completed before the strike began, Alexander said.

Assistants to the writers also were suspended after being paid through the end of the week, Alexander said.

Gregg Mitchell, a spokesman for the writers' union, didn't immediately return a message seeking comment.

`Ellen'

Winship, the guild's eastern president, criticized comedian Ellen DeGeneres, a guild member, for resuming production of her talk show ``Ellen'' after shutting down for only one day. The union issued a statement saying DeGeneres, scheduled to tape in New York on Nov. 19-20, was ``not welcome'' in the city.

DeGeneres resumed taping because the production company, Telepictures Productions, risked legal action from the 220 stations that buy the syndicated show, according to an e-mailed company statement. A contract with stations requires delivery of original material, the company said.

DeGeneres isn't in violation of union rules, spokeswoman Kelly Bush said. ``She is performing, improvising, not writing,'' Bush said in an e-mail.

Networks will be forced to air more reruns and reality shows in lieu of comedies and dramas if the strike continues through the end of the year.

Walt Disney Co. Chief Executive Officer Robert Iger, whose company owns ABC, said yesterday the network may be forced to change its schedule if the strike runs more than four weeks. News Corp.'s Fox said on Nov. 7 it will delay the January return of the drama ``24.''

Disney, based in Burbank, California, fell 89 cents to $32.74 in New York Stock Exchange composite trading. GE fell 64 cents to $38.38. CBS Corp. declined 52 cents to $26.74 and Class A shares of News Corp., which owns Fox, fell 26 cents to $21.27.

To contact the reporters on this story: Michael White in Los Angeles at mwhite8@bloomberg.net; Andy Fixmer in Los Angeles at afixmer@bloomberg.net

Last Updated: November 9, 2007 23:19 EST