Effectiveness of Atimycin‐A as a Toxicant for Control of Invasive Asian Swamp Eels

Abstract

AbstractThe Asian swamp eel Monopterus albus is native to southeast Asia but has established populations in several locations within the United States. These eels grow up to 1 m long and may prey on or compete with native fishes and amphibians. Additionally, these eels are obligate air‐breathers, can survive long periods out of water, and will travel over land in search of new habitats when necessary. As early as 1990, Asian swamp eels were introduced to several ponds at a local nature center near Atlanta, Georgia, within the Chattahoochee River drainage basin; individuals have since migrated to an adjacent marsh of the Chattahoochee River. Because this population is relatively contained, several methods for control, containment, and possible eradication are being investigated. Juvenile and adult swamp eels primarily obtain oxygen through surface air, although very young eels absorb oxygen directly through their skin. Because they are obligate air‐breathers, standard piscicides (e.g., rotenone and antimycin‐A) that are transmitted across the gill membrane may not be effective. Nonetheless, we tested the effectiveness of antimycin‐A on 2–3‐week‐old Asian swamp eels in case transmission occurred across the epidermis. We tested antimycin‐A concentrations of 2, 5, 10, and 100 nL/L (ppb). No concentration was effective at killing Asian swamp eels, although golden shiners Notemigonus crysoleucas were susceptible at 10 nL/L. Eels that have not undergone metamorphosis (<10 d old) may be susceptible to piscicides such as antimycin‐A, but the lack of effectiveness at the early life stage we tested indicates that eradication through such toxicants probably is not a feasible control method.