With the impact of predators on songbird populations featuring heavily in the news, the public are keen to know what they can do to help. Many predators can be found in gardens, and the BTO has produced free guides to advise armchair birdwatchers.
It is an issue that divides garden birdwatchers. Whether it is a Sparrowhawk swooping stealthily to take a Robin, a Magpie raiding a Blackbird nest, or a moggy prowling for House Sparrows, the impact of predators on songbird numbers stirs up heated debate. The act of predation can be more obvious in gardens, and householders have been seeking unbiased, scientific information about the important issues faced and practical tips on how to help their songbirds.
Sparrowhawk and Great Tit, Sandy Point, Hampshire (Photo: Andy Johnson)
There is concern, for example, that smaller birds that gather at feeding stations are an easy target for predators such as Sparrowhawks, but steps can be taken to help tip the balance. The BTO Garden BirdWatch team recommends positioning hanging feeders close to tall and dense vegetation, enabling smaller species to grab food and, if necessary, flit quickly into cover. Moving feeders regularly is also a top tip, since Sparrowhawks tend to follow regular flight paths through gardens.
Cats are thought to take some 55 million birds in British gardens every year, including Red-listed species such as House Sparrow and Starling. Various cat deterrents can help to reduce this toll, with sonic devices being particularly effective if moved regularly to prevent cats learning how to avoid their sensors.
Blackbird, Rotherham, South Yorkshire, "rescued from the jaws of the local cat this morning." (Photo: John Gray)
Dr Tim Harrison of BTO Garden BirdWatch commented: "Those who have a predator visit their garden face many tricky questions. Should I keep feeding birds if I see a Sparrowhawk? How can I reduce the number of birds that are taken by my cat? These and other questions are addressed in the free guides produced by the BTO Garden BirdWatch team."
He added: "With Sparrowhawk numbers having recovered in recent decades and some nine million cats in the UK — around one for every seven people — there is understandable concern about the impact of predators on songbird numbers. The public need impartial, scientific advice, and this is where we can help."
To get the free guides, email gbw@bto.org.
Newson, S.E., Rexstad, E.A., Baillie, S.R., Buckland, S.T. & Aebischer, N.J. (2010). Population changes of avian predators and grey squirrels in England: is there evidence for an impact on avian prey populations? the British Ecological Society's Journal of Applied Ecology, 47, 244-252 doi: 10.1111/j.1365-2664.2010.01771.x. To view an abstract of the paper visit www3.interscience.wiley.com/journal/117972213/home.
