Chough

Description

The adult of the "nominate" subspecies of the red-billed chough,P.p.pyrrhocorax,is 39–40 centimetres (15–16 inches) in length,has a 73–90 centimetres (29–35 inches) wingspan,and weighs an average 310 grammes (10.9 oz).Its plumage is velvet-black,green-glossed on the body,and it has a long curved red bill and red legs.The sexes are similar (although adults can be sexed in the hand using a formula involving tarsus length and bill width)but the juvenile has an orange bill and pink legs until its first autumn,and less glossy plumage The red-billed chough is unlikely to be confused with any other species of bird.Although the jackdaw and Alpine chough share its range,the jackdaw is smaller and has unglossed grey plumage,and the Alpine chough has a short yellow bill.Even in flight,the two choughs can be distinguished by Alpine's less rectangular wings,and longer,less square-ended tail The red-billed chough's loud,ringing chee-ow call is clearer and louder than the similar vocalisation of the jackdaw,and always very different from that of its yellow-billed congener,which has rippling preep and whistled sweeeooo calls.Small subspecies of the red-billed chough have higher frequency calls than larger races,as predicted by the inverse relationship between body size and frequency