Five hundred pounds of invasive Burmese pythons: That’s what wildlife experts in southwest Florida said they recently captured when they discovered a large ball of mating snakes — including one more than 16 feet long — in Collier County.

The Conservancy of Southwest Florida, located near Naples, said the catch came earlier this month during National Invasive Species Awareness Week.

A photo provided to Scripps News West Palm Beach by the conservancy showed wildlife biologist Ian Bartoszek with a massive mating pile of pythons.

According to the conservancy’s Facebook page, the group caught 11 pythons weighing a total of 500 pounds.

“For 10 years, we’ve been catching and putting them (Burmese pythons) down humanely,” Bartoszek wrote on  Facebook. “You can’t put them in zoos and send them back to Southeast Asia. Invasive species management doesn’t end with rainbows and kittens. These are remarkable creatures, here through no fault of their own. They are impressive animals, good at what they do.”

The U.S. Geological Survey considers Burmese pythons one of the most concerning invasive species in southwest Florida, especially in Everglades National Park.

It’s so concerning that Florida holds an annual hunt, dubbed the “Python Challenge,” to remove them.

The Conservancy of Southwest Florida said the Burmese python is one of the largest species of snakes in the world and has become an “established apex predator” in the Everglades.

The snakes, native to Southeast Asia, were brought to Florida through the pet trade starting in the 1970s and were first observed in Everglades National Park in 1979.

“Burmese pythons are thought to be responsible for a 90% decline in native mammal populations across their established range,” the Conservancy said on its website.

This story was originally published by Matt Papaycik at Scripps News West Palm Beach.