MIAMI - The alligator has some foreign competition at the top of the Everglades food chain, and the results of the struggle are horror-movie messy.

A 13-foot Burmese python recently burst after it apparently tried to swallow a live, six-foot alligator whole, authorities said. The incident has heightened biologists' fears that the nonnative snakes could threaten a host of other animal species in the Everglades.

Over the years, many pythons have been abandoned in the Everglades by pet owners. Now it is unknown how many pythons are competing with the thousands of alligators in the Everglades, but at least 150 have been captured in the past two years.

Pythons could threaten many smaller species that conservationists are trying to protect, including other reptiles, otters, squirrels, woodstorks and sparrows.