A new population of non-native Asian swamp eels, a highly adaptable predatory fish, has been found near the eastern border of Everglades National Park in the area of Homestead, Fla. According to the USGS biologists who discovered this new population in December, the eels appear to represent a separate introduction from previously discovered swamp eel populations in Georgia, north Miami, and Tampa because of the widely separated ranges and apparent genetic differences between the Homestead population and the north Miami and Georgia populations.
The eels have not been found within Everglades National Park, although the latest discovery places the eels within a kilometer of the park boundary, said Dr. John Curnutt, a biologist with the USGS Florida Caribbean Science Center in Miami, who is coordinating the monitoring studies of this new population.
"These fishes have the attributes necessary to successfully invade and colonize the Everglades and other freshwater southeastern wetlands, where they could adversely affect native fishes, amphibians and invertebrates through predation," said Curnutt. "They have the potential to disrupt food webs, eat native species, and compete with native fish and wading birds for food. The interconnectedness of the waterways and the eel's biology pose substantial risks of the species becoming established in the Everglades."
Biologists have been monitoring the distribution of this new population since its discovery in December and are studying the effects on native species of the swamp eels discovered last year in Florida.
Of particular concern to scientists and resource managers is that these highly adaptable eels have the ability to thrive in a wide variety of natural habitats and in adverse conditions. In addition to marsh and swamp habitats, Curnutt said the fish survives quite well in ponds, canals, roadside ditches and rice fields -- "just about any freshwater habitat with
Contact: Catherine Haecker
United States Geological Survey