Life at the Top (of the Food Chain)

Monitoring the impact of chemicals on UK wildlife and ecosystems

A bird of prey swoops through the sky. It’s an awesome sight. But it’s not just this sublime grace that attracts attention. For scientists, these predators at the top of the food chain are the perfect litmus test of the health of ecosystems supporting them. That’s why the Predatory Bird Monitoring Scheme, part of the Centre for Ecology & Hydrology’s LWEC-accredited Biogeochemistry Programme, has monitored their exposure to toxic metals and other contaminants for over 40 years. And it’s why the Royal Society for the Protection of Birds (RSPB) has now become a funding stakeholder.

“The scheme provides vital information to help identify what chemicals predatory birds are being exposed to and whether they represent a threat to individual birds and their populations”, says the RSPB’s Jeff Knott.

Lead shot, pesticides, chemicals used as flame retardants in furniture and other products – these are some of the substances that can infiltrate food chains.

“By studying the eggs and carcasses of birds of prey, we can gain real insight into what’s happening within an ecosystem,” says Lee Walker, the scheme’s co-ordinator. “For instance, 5-10% of UK barn owls have assimilated levels of rodenticide large enough to be cause for concern. Our monitoring of barn owls also provides a measure of whether efforts to reduce exposure of wildlife are working – key information for one of our funders, the Campaign for Responsible Rodenticide Use.”        

The Predatory Bird Monitoring Scheme is also part of a new collaborative network funded by the Natural Environment Research Council. WILDCOMS (Wildlife Disease & Contaminant Monitoring and Surveillance) brings together different UK surveillance programmes to provide an improved overview of potential threats to wildlife.

“WILDCOMS should help us identify emerging risks much quicker than ever before”, Lee Walker explains.