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Message: <blockquote data-quote="hannu" data-source="post: 1249292" data-attributes="member: 19244">I collected here a few features from the notification of Finnish RC concerning the Swift observations in autumn 2004, which should help to differ Pallid Swift from Common Swift. Notice that most of them are mentioned earlier posts.Common Swift’s head looks smaller and rounded, whereas head looks bigger / broader and flatten in Pallid Swift. Common Swift’s belly looks on the average more slim than Pallid Swift’s. Pallid Swift’s primary wing is wide and it’s front edge seems to be rounded, but back edge rather straigth. Common Swift’s primary wing is narrower than Pallid Swift’s and it looks crescent. The fork of tail is long and deep in Common, whereas it’s shorter and lower in Pallid. Also the base of tail looks usually more bulky in Pallid than Common.Common Swift’s under wing-coverts are widely dark. Both secondary and primary median coverts are as dark as the front edge of wing and thus darker than all greater coverts. Pallid swift’s median coverts looks completely or mainly as pale as greater coverts, thus dark area is limited (often diffused) to the narrow area of the front edge of wing. Both species can be wide throat patch, but it contrasts strongly to the side of head in Common Swift, whereas throat patch diffuses uniformly to the side of paler head in Pallid Swift. Also the throat patch continues wide usually in the lower part of throat in Pallid Swift, whereas the shape of patch's lower edge is more rounded or oval in Common Swift.  Also the darkest area of head is clearly rather small dark eye mask in Pallid Swift, thus it clearly contrasts to  the neck, throat and crown.Both species can be so called scale-type figures in the belly.</blockquote>

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