City pigeons’ taste for waste could help to boost human health

THEY are the scourge of British streets and dubbed “rats with wings” for their unhygienic habits.

But scientists believe an army of urban pigeons could be recruited to help prevent the spread of disease and toxins by acting as constant “biomonitors”.

The birds’ ability to spread out and occupy all parts of a city could be crucial in keeping dangers to human health at bay, say experts.

Rebecca Calisi-rodriguez, of the University of California, believes pigeons are a perfect tool for monitoring dangerous pollutants because they live off waste and inhabit the same areas as city dwellers and are exposed to the same contaminants.

The team said that pigeons could serve as “the proverbial canary in the coal mine”.

“Pigeons have existed for ages in proximity to us, eating the same food, drinking and being exposed to the same water sources, soil, air, pollution,” said Dr Calisi-rodriguez, associate professor of neurobiology, physiology and behaviour.

“They have a very small home range, spending the their life within a few neighbourhood blocks. And because they are alive, they process these chemicals in their bodies. This offers up the opportunity to not only find toxin hot spots in our environment, but to understand how these toxins affect biology.”

There are 18million feral pigeons in Britain, so scientists would have a huge supply of birds which could act as biomonitors. In a recent study, the team set out to find if pigeons could highlight areas high in lead pollution.

Although lead has been banned from products for decades – because it harms brain development – it is still present in cities, often in old painted street furniture, or play equipment.

Dr Calisi-rodriguez studied the blood levels of pigeons and children living in New York between 2010 and 2015 and found that both experienced similar patterns of lead in their blood.

The team is even monitoring the genetic make-up of the birds to see how stress affects DNA. The research was presented at the annual meeting of the American Association for the Advancement of Science in Austin, Texas.