In this guest blog, RSPB Conservation Scientist Lucy Mason talks about our work at Otmoor to protect lapwing numbers and cut down red kite predation using free meals as a distraction.
Diversionary feeding of birds of prey, where substitute carrion is placed at certain locations, has already enjoyed success as an effective way of reducing red grouse predation by hen harriers and little tern predation by kestrels. So, looking at its potential in other areas, we are embarking on a two-year scientific study to test the efficacy of using this technique to reduce red kite predation of wader chicks, especially lapwing, in Oxfordshire, near our Otmoor reserve.
Before describing our diversionary feeding project in more detail, it is worthwhile taking a brief history lesson. Lapwing and other waders were once widespread as nesting birds across lowland England. But changes in the countryside, largely driven by modern farming policy, have squeezed these birds out of the wider landscape to a point where sites like Otmoor are one of the few areas where these birds can flourish. Before the Otmoor nature reserve was established in 1997, drainage and arable cultivation had eroded the wildlife value of the site to a point where only a remnant of the once widespread wader population survived. Subsequent large-scale restoration of wet grassland has enabled the recovery of many wetland species, including lapwing.
Our efforts combined with the ongoing decline of waders means that Otmoor is now the most important site for breeding waders in central England. Eighty years ago, the red kite was a truly rare bird in Britain with only 10 pairs, all confined to the hanging oak woodlands of mid Wales. The red kite was reintroduced to the Chilterns in 1989 with the first breeding taking place in 1992; at a time when the lapwing was already an extremely localised bird in central England. We believe, the red kite’s recovery is one of the greatest conservation successes of recent times.
We trust that the habitat work that we have completed at Otmoor for the benefit of waders will encourage these birds to re-colonise the surrounding Upper Thames river valleys. The biggest single factor affecting lapwing is the lack of suitable wet grassland habitat in the surrounding landscape.
As populations of waders have become concentrated in fewer and fewer sites, the risk of predation increases in these honey-pot sites. We have undertaken a lot of work to reduce predation by mammals, such as foxes. The installation of anti-predator fences has stopped mammalian predation, but it has concentrated nesting waders into a smaller area, which at times can attract the attention of red kites.
We will use the trial to see whether targeted diversionary feeding during the wader breeding season can reduce predation rates in the fenced areas of the site; and to assess whether reductions in predation rates by red kites result in more wader chicks being recruited into the adult population. Overall we will be testing whether red kite diversionary feeding could be a practical, publically-acceptable and cost-effective management tool to boost lapwing numbers on Otmoor.
We encourage the public not to feed red kites and it is important that we highlight the difference in our view between diversionary feeding and supplementary feeding. The trial will provide diversionary food in a controlled way which aims to lower red kite predation of wader chicks – so we will only undertake this targeted measure during the limited period when waders have chicks. Supplementary feeding of red kites, which has become an important issue in the Chilterns, is done by those people who want to encourage these birds year round into gardens so they can obtain better views of these magnificent raptors. We understand the desire to see these raptors – we like to watch them too – but supplementary feeding of red kites is detrimental to red kites as it doesn’t encourage them to forage and disperse and it doesn’t provide the diet these birds need: red kites are used to quite a poor diet of carrion, so strings of prime sausages –albeit well-meant - don’t provide the roughage these birds need in their diet.
We look forward to the start of this project, which we hope will help improve understanding of this non-lethal method of reducing predation of conservation-dependent species by birds of prey.