Snakes Wreak Havoc In Florida Everglades (via Simon Reames)

Giant snakes appear to be wiping out the mammal population of Florida's Everglades, it is being warned.

The snakes, including huge pythons and constrictors believed to be pets turned loose by their owners, have been eating large numbers of animals such as raccoons, opossums and bobcats.

According to a study, sightings of medium-size mammals have dropped dramatically over the past 11 years - as much as 99% in some cases.

Scientists fear the pythons could be disrupting the food chain and upsetting the Everglades'environmental balance in ways difficult to predict.

"The effects of declining mammal populations on the overall Everglades ecosystem, which extends well beyond the national park boundaries, are likely profound," said research scientist and co-author of the study John Willson.

"The magnitude of these declines underscores the apparent incredible density of pythons in Everglades National Park," said co-author professor Michael Dorcas.

Tens of thousands of Burmese pythons, which are native to Southeast Asia, are believed to be living in the Everglades, where they thrive in the warm, humid climate.

While many were apparently released by their owners, others may have escaped from pet shops during Hurricane Andrew in 1992 and have been reproducing ever since.

Burmese pythons can grow to be 26ft (8m) long and weigh more than 200lbs (90kg).

They and other constrictor snakes kill their prey by coiling around it and suffocating it and have been known to swallow animals as large as alligators.

Florida banned private ownership of Burmese pythons in 2010.

A federal ban on the import of Burmese pythons and three other snakes was announced earlier this month.

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