Invasion Science Institute

Invasive Swamp Eels

The Asian swamp eel is a unique, air-breathing fish native to Southeast Asia, thriving in muddy, stagnant waters. Unlike most eels, it has a long, slimy body and can survive out of water for extended periods. Its adaptability allows it to inhabit diverse environments, from rice paddies to swamps.

They are an invasive species in the U.S., disrupts ecosystems by preying on native species and outcompeting local wildlife. Its adaptability and ability to thrive in various habitats, including wetlands and drainage systems, enable it to spread rapidly, posing significant ecological and economic challenges.

In Florida, it is found in several southeast box-cut canals, as well as the Little Manatee River and Bullfrog Creek drainages near Tampa, where it has been established since 1997 and is expected to gradually spread, though it is not anticipated to significantly affect native fish populations. The swamp eel thrives in shallow, slow-moving, or stagnant waters with dense vegetation and often burrows into muddy bottoms. It can survive in low-oxygen environments due to its ability to breathe air. In its native range, it lives in various water bodies such as ponds, canals, and swamps, and can even endure in moist mud during dry periods.

Identification:

Snake-like body tapering to a point
Small eyes and tiny scales; Finless
Dark reddish-brown with light tan to orange abdomen; some may be light orange, pink, or white with dark calico-like markings
Heavy mucous coating aids burrowing
Generally sluggish and secretive

Invasive Swamp Eels being sold in a bucket at a market