DALLAS (AP) — Flight cancelations have spiked at American Airlines, which is fighting with unhappy pilots, and the carrier will reduce flights at least partly because of staffing shortages.

American will cut its schedule for the rest of September and October by 1 to 2 percent due to "a number of factors" including an increase in pilots calling in sick and maintenance reports filed by flight crews, said airline spokesman Bruce Hicks.

American canceled more flights on Sunday and Monday than any other airline, according to flight-tracking services.

Hicks said the company was "constantly evaluating our schedule based on operational and staffing resources" and seasonal patterns. He said the AMR Corp.-owned airline was making changes to ensure reliable service for passengers.

The cancelations come a few days after American imposed new cost-cutting terms on its pilots, including outsourcing more flying jobs to other airlines and terminating one of the pilots' retirement programs in November. Pilots rejected more-generous terms in the last contract offer from American, which has been under bankruptcy protection since November.

Last week, the union sent out ballots for a strike-authorization vote, although federal officials have not cleared the way for a legal strike at the nation's third-biggest airline.

Allied Pilots Association spokesman Tom Hoban said Monday that the union neither sanctioned nor supported a sickout.

"That being said, you've got 8,000 pilots that are witnessing a handful of senior executives at American Airlines that have chosen in a very deliberate manner to dismantle and destroy their profession," Hoban said. "To say that the pilots at AA are not happy would be the understatement of a lifetime."

American canceled 57 flights as of late afternoon Monday, more than the next nine airlines combined, according to FlightAware.com, a flight-tracking service. Another company, FlightStats Inc., said American canceled 95 flights, or about 5 percent of its schedule.

In July, the most recent month for which government figures are available, American canceled 1.2 percent of its flights, slightly below the industry average.

American also topped all airlines with 90 cancelations out of 318 industrywide on Sunday, and had already scrubbed 22 flights scheduled for Tuesday, according to the FlightAware, which noticed an increase in American cancelations in early September.