Barn owls are efficient natural rodent controllers facing habitat loss and secondary poisoning — with nest box programs providing habitat while reducing farmer reliance on rodenticides that harm owls and other wildlife.
Barn owls killed through secondary rodenticide poisoning die through anticoagulant toxicity — internal bleeding that causes progressive weakness, pallor, and death over days. This is a painful and prolonged death for an animal that is itself providing valuable pest control services. Road mortality causes traumatic acute injury. Nest box programs directly benefit barn owl welfare by providing breeding habitat that has become scarce as old agricultural buildings are converted or demolished. The ecological rationale and the welfare rationale align perfectly: supporting barn owl populations through nest boxes and rodenticide reduction provides pest control benefits while eliminating the welfare costs of poisoning and supporting a species whose habitat has been systematically degraded.