March 10 2014 Latest news:
Wednesday, December 11, 2013
Common crossbills aren’t called crossbills for nothing – these stocky, noisy members of the finch family have mandibles that cross over.
The tip of the upper half of the extraordinary bill curves down, and the tip of the lower half curves up, and for good reason. It enables the birds to prise open conifer cones to reach the seeds on which the birds feed – a specialised adaption for a specialised feeder. The species’ exclusive diet means that common crossbills are found virtually exclusively in conifer forests – in Suffolk mainly in the Brecks and in the coastal strip.
The diet also means the species is dependent on conifer seed crops and if these fail across northern and eastern Europe birds often move in large numbers – known as irruptive movements – to the pine forests of Britain.
The UK is currently hosting several parties of rarer crossbills – the large parrot crossbill and the smaller two-barred crossbill, which have “irrupted” in search of their particular conifer seed supplies. Parrot crossbills have recently been found in Essex, at Shoeburyness, and in Suffolk, at Tunstall Common and at Mayday Farm in the Brecks – much to the delight of rarity-hunting birders.
See our gallery - top right - for photos of the crossbill, taken by Margaret Holland, of Ipswich.