GREEDY rats and squirrels are gobbling up grain intended to help struggling farmland birds make it through the winter say Hampshire researchers.

A new study, carried out by the Fordingbridge-based Game & Wildlife Conservation Trust (GWCT) discovered that more than two thirds of the food farmers put out for game birds and song birds is taken by rodents and common birds such as pigeons and crows.

The two-year study, carried out by Dr Carlos Sanchez-Garcia and supervised by Dr Francis Buner from the GWCT, involved putting camera traps on nearly 260 game feeders containing wheat grain on three lowland farms in Oxford and Hampshire during the winters of 2012 and 2013.

Over this period more than 160,000 photographs showing the various visitors to the feeders were taken and analysed.

Game feeders are usually placed near or within tall vegetation such as hedgerows.

As part of the study, the researchers wanted to identify whether location made a difference to the amount of food consumed by the rates and other undesirable visitors, whilst not deterring game and songbirds.

In the trial, feeders along hedgerow cover were attractive to all species except corvids who preferred more open fields.

When the feeders were moved to open fields the gamebirds and songbirds used them but not the rats.

When the feeders were located in the hedgerow and periodically moved 25 metres from the original location the gamebirds and songbirds located them at the new locations within three days, whereas the rodents needed between two and four days to find them.

Over the two-year period 47 individual species were recorded visiting the feeders (33 birds and 14 mammals), with just 10 species accounting for 90 per cent of the wildlife appearing in the photographs.

Top of the list were pheasant, woodpigeon, rat, mice, dunnock, grey partridge, blackbird, yellowhammer, rook and red-legged partridge.

In addition, 15 species of songbirds – including six UK species of conservation concern including, yellowhammer, house sparrow, linnet, song thrush and starling were recorded using the feeders.

Dr Sanchez-Garcia says: “This large scale study identifies that current feeding practices used by farmers and gamekeepers need to be revised to ensure that mainly target species and not pests are the beneficiaries of this important food source.

“Our previous studies stress the need to continue feeding in late winter and we would recommend that feeders are placed along hedgerows when efficient control of rats is maintained and to place feeders in open fields when no efficient rat control is carried out.

"A regular change of the feeder location (every seven to 10 days) is also recommended to reduce the impact of rodents and other unwelcome visitors.”