Southwest Airlines Executive Warns that Industry Needs Low-Cost Options.

Byline: Gretchen Fehrenbacher

Aug. 29--Southwest Airlines' top executive says some of today's biggest carriers won't be around in a decade, unless they can cut fares or stake out specialty markets.

"If you are not a low-cost carrier, I don't think you will be able to survive," Colleen Barrett, Southwest's president and CEO, told a downtown Portland business gathering Thursday.

"It's going to be very interesting to see who has the staying power," she said.

Southwest has grown to be the nation's fourth-largest passenger carrier by focusing on low fares and frequent flights in localized markets. She said carriers that survive the next several …