Wild Earth Guardians, the Center for Biological Diversity, the Humane Society of the United States, and the Fund for Animals are all threatening to sue the US. Fish and wildlife Service for their use of pesticides. The groups plan to file the lawsuit sometime in the next 60 days, if the agency continues to use the chemicals sodium cyanide and Compound 1080, which they say ends up killing more than just the target animal, like a nuisance coyote.