Experimental farm practices aid bird recovery

Skylark is one of the species reliant on agricultural land which has declined in many people's lifetime. Photo: Chris Gomersall (rspb-images.com).
Skylark is one of the species reliant on agricultural land which has declined in many people's lifetime. Photo: Chris Gomersall (rspb-images.com).
Many bird species reliant on agricultural landscapes have been declining sharply since the 1970s, but experiments on RSPB farms show how these trends could be reversed.

With many species of farmland bird – including iconic songbirds such as Skylark and Yellowhammer –  losing more than half of their British breeding pairs over the last four decades (coinciding with a period of rapid and intense agricultural change), extreme concerns have been raised about these species' futures. Both the Game and Wildlife Conservation Trust (GWCT) and the RSPB have conducted a wealth of peer-reviewed research into the causes of the declines and how to manage them.

A new study by the two organisations published in the journal Bird Study has revealed that implementing such management solutions has brought about the rapid recovery of a broad range of songbirds at each charity’s demonstration farm. The study was performed at two farms, 42 miles apart in eastern England: GWCT’s 292-hectare Loddington Farm, in Leicestershire; and the RSPB’s 181-hectare Hope Farm, in Cambridgeshire.

Providing safe nesting sites and access to food has allowed farmland bird numbers to double or even treble in just five to 10 years. The recovery in bird abundance at these sites has been in stark contrast to the continuing declines seen in the surrounding countryside. This suggests that a greater roll out of wildlife-friendly farming measures should lead to a recovery in farmland birds in the wider countryside.

At the Leicestershire site, where predators occurred at a high density, the recovery of species such as thrushes and finches – which make open ‘cup-like’ nests – required predator management as well as habitat improvement in order to boost numbers. In comparison, at the Cambridgeshire site, where the density of predators was low, farmland bird recovery was achieved solely by habitat management. Predator density is probably a function of landscape type, this being wooded with mixed farmland in Leicestershire, but open, flat and mainly arable in Cambridgeshire.

Previous studies have found no evidence that crows and Magpies limit songbird numbers across the country as whole, but that they may do so locally. Further research is needed to understand how typical the Leicestershire and Cambridgeshire situations are compared to the rest of the country.

Dr Nicholas Aebischer of the GWCT is first author, and has studied the ecological needs of farmland birds for 25 years. He said: “The dramatic recovery in songbird numbers within a few years is evidence that we have successfully identified the ecological requirements of declining farmland birds, and demonstrated that we know how to satisfy them at a local scale. We encourage farmers and land managers to visit our farm, learn about the practicalities of management and hopefully leave filled with enthusiasm to replicate our success on their own land.”

Dr Will Peach from the RSPB’s Centre for Conservation Science is another of the study’s authors, and has been studying farmland birds for more than 20 years. He said: “The hemorrhaging of some of our favourite songbird species from our countryside has been one of the greatest conservation issues that we have faced over the last two decades. Although restricted to two sites, our study highlights that creating suitable nesting and feeding habitats  is potentially key for the recovery of threatened farmland birds , and we know that many farmers are eager to help nature through properly-funded wildlife-friendly farming schemes.”