Peregrine Falcon: Ecology and Welfare
The peregrine falcon (Falco peregrinus) is the world's fastest animal in a stoop — exceeding 320 km/h in a dive. Its dramatic decline due to organochlorine pesticides and its remarkable recovery following pesticide bans represents one of conservation's great success stories. Today, peregrines nest across Britain including in city centres.
Ecology and Hunting
Peregrines are specialist aerial predators of medium-sized birds, primarily taken in flight. Their hunting stoop — a high-speed dive from above — delivers a killing blow with the talons that stuns or kills prey before it can manoeuvre. This technique requires exceptional eyesight, aerial agility, and anatomical adaptations (nostril baffle structures preventing lung damage at high speed; dense bone structure to withstand impact forces).
Urban peregrines prey extensively on feral pigeons and starlings — prey that cities provide in abundance. Cathedral ledges, high-rise buildings, bridge towers, and power station chimney stacks serve as cliff substitutes for nesting and hunting vantage points.
Conservation Recovery
Organochlorine pesticides (DDT and related compounds) accumulated in bird-eating raptors through the food chain in the 1950s-60s, causing eggshell thinning, reproductive failure, and population collapse. The peregrine population in Britain fell to approximately 360 pairs by the mid-1960s. Following pesticide bans, populations recovered steadily — to around 1,800 pairs by 2014. This recovery demonstrated that wildlife populations can recover when the causal threat is removed.
Ongoing Welfare Threats
Despite legal protection, peregrines face ongoing threats: illegal persecution (particularly poisoning and nest disturbance in areas where they prey on racing pigeons), egg theft by collectors, and urban disturbance during nesting. Second-generation anticoagulant rodenticides are found in urban peregrine livers, with potential sublethal welfare effects.
CCTV nest cameras on urban nesting sites reduce human disturbance while engaging public interest in local peregrines — creating constituency for their protection.
Individual Welfare Considerations
Injured peregrines require specialist raptor rehabilitation. Impact injuries (window strike, vehicle collision) are most common in urban populations. Imprinting during rehabilitation must be avoided to enable release — isolation from human contact and use of appropriately imprinted foster birds maintains wild behaviour in rehabilitated individuals.