People who feed birds in their gardens may be putting them at risk of disease, a study has shown.
The research, conducted by the British Trust for Ornithology (BTO) and the Zoological Society of London (ZSL), looked at 25 years of data on wild bird health threats.
The research found that that garden feeding could promote transmission of some diseases. It was said that this was because birds would be encouraged to populate in the same areas repeatedly, possibly exposing them to species they would not normally interact with.
A form of bird pox was said to have emerged recently and becoming more common, while the threat of salmonella is declining. Risk of disease could also be increased if feeding areas are not kept clean. The report also warned that if birds look sick, food should be withdrawn temporarily.
Kate Risely, from BTO, said: “We’re calling on everyone who feeds wild birds to be aware of their responsibilities for preventing disease. Simple steps we’d recommend include offering a variety of food from accredited sources; feeding in moderation, so that feeders are typically emptied every one to two days; the regular cleaning of bird feeders; and rotation of feeding sites to avoid accumulation of waste food or bird droppings.”
Dr Becki Lawson from ZSL’s Institute of Zoology added: “Our study shows how three of the most common diseases that affect British garden birds have changed both dramatically and unpredictably over the past decade, both in terms of the species they affect and their patterns of occurrence.”