Proceedings of the Vertebrate Pest Conference

Feral nutria were established near Blackwater National Wildlife Refuge (BNWR) in Dorchester County Maryland in 1943 after a failed attempt to create a fur industry. As the population expanded in number and distribution, natural resource managers began to notice an accelerating trend in wetland loss in the areas most heavily infested by nutria. By the late 1980s, an estimated 35,000 nutria occupied BNWR, which had seen approximately 5,000 acres of emergent marsh converted to shallow open water habitats and mudflats. Exclusion studies in the 1990s demonstrated a direct link between nutria and marsh loss, and by 2000 officials had procured funding to initiate an eradication feasibility study. This paper provides a historical overview of the eradication campaign that has been underway since 2002. The Chesapeake Bay Nutria Eradication Project (CBNEP) is a cooperative partnership between the U.S. Fish and Wildlife Service, USDA Wildlife Services program, and numerous state and non-governmental organizations. The CBNEP employs an adaptive management strategy utilizing systematic trapping carried out by salaried wildlife specialists to eliminate nutria from infested watersheds. We present a phased approach that allows us to continually expand the eradication zone and maintain nutria-free areas with a relatively small staff. Through an active research and development program, we have innovated new tools and techniques for trapping and detecting nutria including: floating trap sets, attractants, decoys, remote triggered cameras, detection platforms, hair snares, and Judas nutria. To date, we have reduced nutria populations to near-zero densities across 250,000 acres of emergent marsh. Based on extensive surveys, remaining populations should be removed by the end of 2014. Following a 2-year verification/biosecurity protocol, we hope to have nutria eradicated from the Delmarva Peninsula by 2017.