Feed the birds – yes or no?
We all like to feed our garden birds. It’s a cheering sight to see robins, finches and many others gather outside the window. But will feeding them create a dependency? And will they lose their ability to forage for themselves and their chicks?
“Arguably the greatest concern many people have is that birds will become reliant on these handouts,” writes Dr Kate Plummer, Senior Research Ecologist at BTO (British Trust for Ornithology). “But there is no discernible evidence that garden feeders create dependency (other than during extreme weather conditions). On the contrary, research suggests that food gathered at feeders typically makes up less than 20% of the diet of Blue Tits in winter, and, irrespective of how readily available feeders are, parent birds almost exclusively feed their chicks on natural food stuffs.”
“In other words, supplementary food is just that: supplementary. There is no reason to suggest that feeders cause birds to lose their ability to forage for natural foods.”
But does providing food affect the numbers and species of birds we see around us?
“Inevitably, changing bird feeding habits can be linked to the large-scale restructuring of garden bird communities and the growth in urban bird populations across Britain,” warns Plummer.
“Feeders have become better at attracting a broader range of species over time, with many species using feeders much more frequently now compared to 40 years ago. Several farmland species are visiting garden feeders in winter. This is because altered farming practices have led to a depletion of natural foods, such as seeds and insects... So if the survival prospects of birds are being hindered by the environmental impacts of humans on natural food supplies more widely, then perhaps our feeders are helping to redress the balance in some small way?”
Plummer goes on to say, “My biggest concerns around garden bird feeding include the risk of disease, food contamination and poor nutrition."
"Pioneering research led by Dr Becki Lawson and the team at Garden Wildlife Health, alongside BTO’s Garden BirdWatch volunteers, has drawn our attention to the increased risk of disease transmission between birds gathered at feeding stations. Also the possibility that garden birds are being exposed to mycotoxins (in the feed) which are potentially toxic compounds produced naturally by moulds.”
In recent years one victim has been the greenfinch, whose UK population has radically dropped after the species became host to the parasite trichomonas, previously only seen in pigeons and doves. The repeated gathering of many different bird species in one place, day after day, and exposure to each other's droppings and regurgitated food is thought to add to the risk.
The BTO’s recommended feeding rules include:
- offering a variety of food from accredited sources
- feeding in moderation, so that feeders are typically emptied every 1-2 days
- the regular cleaning of bird feeders
- and rotation of feeding sites to avoid accumulation of waste food or bird droppings.