Barn Owl Welfare: Rodenticide Secondary Poisoning in the UK

Barn owls are being poisoned by second-generation anticoagulant rodenticides accumulated in their prey, causing welfare impacts and contributing to population-level effects.

Key Facts

Studies show over 90% of barn owls tested in the UK have detectable SGAR residues in their livers
SGARs accumulate in prey species including mice, rats, and voles hunted by owls
High residue burdens impair blood clotting causing internal haemorrhage and death
Barn owls that die from anticoagulant poisoning suffer prolonged internal bleeding before death
Legal use of SGARs under stewardship guidelines aims to reduce environmental contamination

Welfare Considerations

Barn owls with high SGAR liver burdens from consuming poisoned prey suffer impaired blood clotting leading to spontaneous internal haemorrhage. Death from secondary SGAR poisoning is prolonged and painful, with affected birds found unable to fly and bleeding internally. Sub-lethal exposure impairs the immune system and reproductive success. The very high prevalence of SGAR residues in UK barn owls means the majority of individuals carry some welfare burden from rodenticide exposure. Integrated pest management reducing rodenticide use protects owl welfare.

What You Can Do

Use rodenticide stewardship guidelines and only as a last resort after other methods
Report dead barn owls to the Barn Owl Trust for residue testing
Support integrated pest management approaches reducing dependence on SGARs
Donate to the Barn Owl Trust monitoring rodenticide impacts and promoting safer alternatives
Advocate for stricter SGAR regulation to protect wildlife from secondary poisoning