Ravens 'Not Behind' Wader Decline

A large crow considered one of the most intelligent native British birds has been ruled out as the cause for a decline in the number of wading birds. Raven numbers in upland areas of the UK have increased over the past 20 years, while waders such as lapwing and curlew have fallen by 50%. Raven feed on the eggs of other birds, but a new study has suggested its links to the decline were weak. It is thought changes to habitat and vegetation and foxes could be to blame. The RSPB and University of Aberdeen's Centre for Environmental Sustainability (ACES) carried out the research. Government agency Scottish Natural Heritage (SNH) helped to fund the project. The new study, published in the British Ecological Society's Journal of Applied Ecology, will help SNH when considering applications to legally kill ravens to protect other species. Ravens have also been blamed by farmers for preying on livestock in the Highlands, Islands and Argyll. Last January, farmers were allowed to shoot more of the crows than previously permitted in an effort to protect newborn lambs and calves. Dr Arjun Amar, a senior conservation scientist with RSPB who led the study, said ravens had undergone a "welcome" recovery over the past 20 years. The scientist said: "While many organisations view these changes as positive, increases in raven numbers have raised legitimate concerns among other groups, because of their perceived impact on prey species, and this can lead to conflict between land managers and conservation organisations. "We hope that this new research will help the licensing authorities balance the need to safeguard populations of vulnerable, recovering predators, whilst at the same time acknowledging and addressing concerns over increasing predator populations." Prof Steve Redpath, director of ACES, said the reasons for upland wader populations suffering so badly had still to be clearly understood. He said: "It is often the case that predators are assumed to be responsible, but this is not always the case. "This research found no strong evidence to suggest that ravens were responsible for changes in wader numbers, implying that we need to look elsewhere to discover the cause for these large-scale declines."