Public Outcry Over Proposed Aerial Pesticide Use in Rio Chama Watershed

Media Contact: Bjorn Fredrickson, New Mexico Wild,, (206) 372-5608

Taos, NM (May 22, 2024) – A proposal to aerially apply pesticides to kill native grasshoppers on federal public lands in the Rio Chama Watershed has sparked significant public outcry for the second year in a row. In January, the U.S. Department of Agriculture, Animal and Plant Health Inspection Service (APHIS) announced this year’s proposal, which is aimed at increasing forage for cattle. The public response to this project was overwhelmingly negative, with over 1,640 individuals voicing opposition during the public comment period.

The affected area includes 25,000 acres in the Cebolla area of Rio Arriba County on primarily Bureau of Land Management (BLM) lands, along with some state land and private property. The area is popular for outdoor recreation, including boating and hiking, and includes the Rio Chama Wilderness Study Area (WSA) and the Chama Canyons Area of Critical Environmental Concern (ACEC). The spray would occur in close proximity to the Rio Chama Wild and Scenic River, the Chama River Canyon Wilderness, the Jicarilla Apache Nation, and an Important Bird Area designated by Audubon.

APHIS proposes to use four different chemicals for the project: carbaryl, chlorantraniliprole, diflubenzuron, and malathion. Commenters emphasized a particular opposition to carbaryl, citing potential harm to non-target species. Carbaryl is highly toxic to insects, including native pollinators, as well as mammals, fish, birds, and larval amphibians. Carbaryl is also a likely human carcinogen and has been known to cause nausea, headaches, dizziness, anxiety, and mental confusion, as well as convulsions, coma, and respiratory depression. 

Additional public concerns revolve around the lack of transparency and public involvement in the decision-making process. Many individuals emphasized the need for a comprehensive analysis of the project’s impacts on a variety of sensitive resources, publicly accessible survey data that demonstrates a need for grasshopper control, and a thorough economic justification before any pesticide use is considered. They stressed that APHIS should develop scientifically sound survey plans and promptly make data available to the public.

“As many New Mexicans know, the public lands within the Rio Chama watershed are treasured for their ecological, cultural, scenic, and recreational values,” said Bjorn Fredrickson, Conservation Director for New Mexico Wild. “Any proposal for pesticide use should be justified by a clear need for action, rigorous environmental analysis, and transparent public process. Despite constructive public comments on numerous deficiencies in the APHIS proposal, the agency has failed to meet any of these basic standards. Further, carbaryl’s adverse effects on both wildlife and human health make its aerial spraying over federal public lands completely unacceptable.”

The New Mexico Environment Department also weighed in with concerns. “The proposed affected area in Rio Arriba County includes the Chama River Canyon Wilderness. The stream segments and wetlands in the Chavez Canyon, Ojitos Canyon, and the Rio Chama within the Chama River Canyon Wilderness are classified as Outstanding Natural Resource Waters (ONRWs),” said the Department in their comments. “Pesticide applications should avoid and provide adequate buffer to water bodies, wetlands and riparian zones, playas and internal draining wetlands (depressions), tributaries, arroyos, acequias and other drainageways to water bodies, and wetlands.”

The public outcry underscores the importance of moving away from widespread use of harmful pesticides and toward sustainable solutions that protect biodiversity and public health, and a need for much improved transparency and public engagement in APHIS projects affecting federal public lands and resources. New Mexico Wild commends the BLM Taos Field Office for halting last year’s spray, citing the need for additional environmental analysis and public transparency. We are optimistic that our public land managers will make the same sound decision this year.