Peregrine falcon recovery from organochlorine pesticide impacts is one of the great wildlife welfare and conservation stories of the 20th century.
Peregrine recovery demonstrates a profound welfare principle: when the primary welfare threat is removed, natural resilience enables recovery. The welfare cost of DDT - reproductive failure through eggshell thinning causing egg loss - was eliminated by banning the chemical. The lesson applies broadly: identifying and removing the primary welfare threat is the most effective single intervention.