Wild Barn Owl Conservation: Rodenticide Poisoning

Barn owls suffer significant mortality from secondary rodenticide poisoning when consuming rodents killed by anticoagulant rat poisons. Safer rodent control alternatives protect these beneficial predators.

Key Facts

Barn owls (Tyto alba) are among the most widely distributed birds globally but declining in many areas
Second-generation anticoagulant rodenticides (SGARs) accumulate in owl tissue through prey consumption
Studies find SGAR residues in over 80% of barn owls tested in the UK — many at concentrations causing internal bleeding
A single barn owl can consume approximately 1,000-2,000 voles annually providing natural rodent control
First-generation anticoagulants are less persistent and accumulate less in predator tissues
SGAR restriction for amateur use in the UK has not been fully implemented despite regulatory intent

Welfare Considerations

Barn owl secondary poisoning welfare involves a pattern of slowly progressive internal bleeding from anticoagulant accumulation that causes debilitating hemorrhage before death. Owls with sub-lethal SGAR exposure show impaired flight, susceptibility to further trauma, and eventual death from hemorrhagic complications without reaching acutely symptomatic levels that would prompt rescue. The chronic, hidden nature of this poisoning means individual welfare harm is rarely observed directly — birds simply disappear from territories. Barn owl as a natural rodent control agent provides practical arguments for rodenticide replacement — a single breeding pair raises 3-5 owlets annually, all providing rodent suppression without chemical risk to the food chain. Supporting barn owl nest boxes as rodent management alongside SGAR replacement prevents welfare harm.

What You Can Do

Replace second-generation anticoagulant rodenticides with first-generation alternatives or non-chemical controls
Install barn owl nest boxes on farms and rural buildings to encourage natural rodent control
Support Barn Owl Trust campaigns against SGAR use in agricultural settings
Advocate for full implementation of SGAR restrictions for amateur and professional use
Report barn owls showing signs of illness to wildlife rehabilitation centers
Learn about integrated pest management approaches that reduce reliance on rodenticides