An Overview of The 2nd National Invasive Rodent Summit

On October 19-21, 2004, the USDA, APHIS, Wildlife Services, National Wildlife Research Center (NWRC) in Fort Collins, CO, hosted the 2nd National Invasive Rodent Summit. The conference was jointly sponsored by the NWRC, the U.S. Fish and Wildlife Service (FWS) and The Wildlife Society’s Wildlife Damage Management Working Group. The conference was a follow-up to the 2001 “Rat Summit” held in San Francisco, CA. Like the “Rat Summit,” this conference emphasized the management of rodents to conserve plants, other wildlife and habitats. The scope of the problem, concerns, species involved, and lands affected were all considered. The conference began with talks covering invasive species management on a national level by personnel from the National Invasive Species Council, the FWS, and the U.S. Armed Forces Pest Management Board. Numerous examples of rodent eradications on islands were presented. Mainland rodent control efforts were presented and noted to be quite different from island eradications, differing in size of area, duration of effort, landownership, hazards and non-target issues, and residue accumulation. A session addressed rodents and disease because many human and livestock diseases are transmitted by rodents or their ecto-parasites. Nutria, an invasive aquatic rodent, presents problems of marsh degradation in Maryland and Louisiana; control efforts and research needs were considered in a special session. While many of the basic methods of rodent control were developed for commensal rodent control in and around buildings and for agricultural situations, new approaches, being investigated and implemented, were discussed. These included IPM/community efforts, trap-barrier-systems, and fertility control. Issues of methods development and registration costs and various constraints remain. There was considerable discussion of assessing the risks of rodenticide use, including primary and secondary hazards, and residue accumulations. Modeling efforts and worst-case scenario investigations have contributed to the understanding and reduction of hazards and have aided in toxicant selection. While many challenges remain, much progress has been made in the control and eradication of introduced, invasive rodents. The conference was well attended with 105 registrants representing 10 countries and territories and 23 states.