Nasa is trying to rid the Kennedy Space Centre of vultures after the shuttle struck one of the birds during lift-off last year on the first flight after the Columbia disaster.

The space centre has set up what it calls a "road kill posse" to quickly clear as many carcasses as possible from the 6,000-acre site (2,400-hectare), in the hope of encouraging the vulture population to relocate by cutting off its food supply.

When shuttle Discovery lifted off the launch pad last July on the first flight since the 2003 Columbia accident, it hit a vulture during its climb to orbit.

Discovery did not suffer any damage that time, from the vulture or from the chunks of foam that fell off its fuel tank during launch. But Nasa fears collisions with the large, carrion-eating birds could damage shuttle heat shields, leaving the spacecraft vulnerable to an accident like the one that killed Columbia's seven astronauts.

"We need everyone's help," the agency wrote in newsletters distributed to the space work force last week. "A crew will be sent to quickly remove the carrion before the vultures are attracted to the free meal."

About 500lb of animal carcasses have been removed since the programme began two weeks ago, the centre said.

In addition to picking up dead animals, the space centre said it was employing other tactics to discourage the vultures, including testing a sound system that would broadcast loud noises and spraying a noxious chemical. The centre said it would also try to trap and remove the birds.

The agency is preparing to resume shuttle launches this summer from the space centre, which lies within a wildlife preserve.

Its roads are dotted with the bodies of possums, raccoons, feral pigs, squirrels, birds and other animals hit by traffic. The centre is asking anyone who sees dead animals to call a road-kill hotline to report the location.