This helped biologists manage wolves and avoid cross-breeding of coyotes and wolves (called "hybridization"). Fish and Wildlife Service (FWS) is evaluating the future of the program and several wildlife conservation organizations have sued the FWS charging that it has "failed to manage the dramatically reduced red wolf population so as to ensure its survival and promote its recovery, engaging in such counterintuitive actions as suspending red wolf reintroductions and ceasing coyote sterilizations."The United States is struggling over human-wildlife conflict issues.