The British lowland countryside is characterised by a network of hedges, a much valued component of our cultural landscape and a nesting habitat for countless birds. Together with RSPB partners, we recently published a paper on the effects of hedgerow structure on the nesting success of these birds. Our previous research at Loddington revealed that controlling crows and magpies had a beneficial effect on nesting success and subsequent breeding numbers of some species, and also that nesting success was influenced by the structure of the habitat in which nests were located.
As management of many hedges has been neglected in recent years, resulting in a more open structure, this could leave nesting birds more susceptible to predation than in the past. Our monitoring of 399 nests over two years revealed that birds were choosing the denser parts of hedges in which to nest. Nest survival was higher in hedges that had been cut four years before than in those that had been cut more recently (in the previous year), and nests fared better in mechanically trimmed, stock-proof hedges than in recently laid or neglected leggy ones.
This is encouraging. While we have shown that the control of crows and magpies can have an important role to play in songbird conservation where landscape characteristics support high numbers of these species, our recent research shows that hedgerow management can also help to improve songbird breeding success on farmland.