NATIONAL BRIEFING / WASHINGTON, D.C.

Burmese pythons and other giant snakes sold through the pet trade could devastate native wildlife in parts of the United States, according to a U.S. Geological Survey study.

The USGS says Burmese pythons, African rock pythons, boa constrictors and yellow anacondas could threaten the ecology of national parks.

The study was prompted by the discovery of Burmese pythons and boa constrictors reproducing in the Everglades. The snakes are thought to have been introduced by people who released their pets. Some of the serpents could survive in colder areas too, the study said.

The report cites the brown tree snake’s impact on Guam. Since its introduction to the island 50 years ago, several native species have been wiped out -- including 10 of its 12 forest birds, most of its bats and about half of its lizards.