Tern, Swift

Conservation status:

Rare Winter Visitor

Description:

Large slender tern, size between Sandwich and Caspian; adult best identified from Lesser Crested by longer, thicker, more drooping waxy yellow bill tinged greenish (slimmer, orange-yellow in Lesser Crested) and by much darker ashy grey upperparts; rump and tail paler grey than back. In summer, black crested cap always broken by white forehead-band (never black as in some Lesser Crested); tail slightly longer, more forked and wings broader than Lesser Crested. In winter, bill pale greenish yellow, but few have washed out yellowish orange bill; crown white with black confined to nape, the black often finely pale-tipped; upperparts as in summer but tail and rump almost as dark as back. Juvenile has pale panel in centre of innerwing above, framed by dark bar on forewing and dark rear covert and secondary bar. Flight steady with shallow wing-beats.