Mosquito Policy Expected to Reduce Pesticide Use on National Wildlife Refuges

Marsh Wren. Photo: Bill Hubick

The U.S. Fish and Wildlife Service (FWS) has proposed a new regulation that is expected to lead to less pesticides being sprayed on National Wildlife Refuges (NWRs). Currently, FWS relies on other agencies to determine when and where pesticides are applied to control mosquito outbreaks that could pose a threat to human health or wildlife populations. Under the new rule, FWS will make these decisions and utilize integrated pest management, both of which could help reduce the amount of pesticides that are applied.

“Mosquito abatement control has resulted in the deaths of thousands of protected migratory birds, especially in Florida, where the pesticide fenthion was routinely used until the Environmental Protection Agency cancelled all uses of the chemical in 2004,” said Dr. Michael Fry, Director of American Bird Conservancy’s Pesticides and Birds Program. “ABC is encouraged by the proposed rule; it has significant protections to avoid ecological damage from pesticides being used for mosquito control efforts on National Wildlife Refuges.”

Sharp-tailed Sparrow. Photo: George Jett

The new rule will allow only registered pesticides to be used on NWRs even if adjacent non-federal lands have received special exemptions to apply banned pesticides such as fenthion, which poses a high risk to birds. Pesticide spraying will also only be allowed after monitoring data has been collected indicating control is warranted.

The draft policy recognizes the natural role that mosquitoes play in wetland ecosystems. Mosquito larvae are an important source of food for wildlife, and spraying pesticides often has negative impacts on non-target species.

Integrated pest management will also enable FWS to use non-toxic alternatives. This can include removing artificial breeding sites, timing the manipulation of water levels for managing wetlands to disrupt the mosquito life cycle, and introducing predators.

The rule does allow one potential loophole, which is that the Secretary of Interior can waive these rules if he/she determines that there is a public health emergency. American Bird Conservancy’s comment letter to FWS argues that this provision is unwarranted, and that only public health officials have the expertise to make the determination of a health emergency.

Approximately 60 NWRs would be affected by this policy. The rule will be implemented when a final decision is published in the Federal Register.