White Throated Needletails, + something else?

To: birding-aus <>
Subject: White Throated Needletails, + something else?
From: Michael Tarburton <>
Date: Sun, 13 Dec 2009 12:10:31 +1100
G'day All

Tom has reminded us of a useful practise: that of having a good look at individual swifts in a flock. It is the best way of finding other species including swiftlets, but be really careful not to mistake martins for swiftlets.

You do have to be careful and have a good long look, as White- throated Needletails themselves vary a lot in size. Australian skins in Australian museums of WTNT have a wing measurement range of 184-217 mm (live birds I have caught varied: 192-220 mm). Weights in museum specimens varied 54 - 154 gm. This has a strong bias on the light side as many museum skins came from birds that had crashed and died after days of not eating - during which time they would have been using up their fat reserves. My sample of live bird weights is 108-126 g.

In trying to differentiate the other needletails you need to look for whether or not there is a white patch on the back between the wings or not, Whether the lores are white & whether the throat is white or brown. The Papuan Needletail has a white throat, chest & stomach & is a much more dumpy bird, looking much shorter than the needletails.

Key to Needletails

Species                         White lores     White back      White throat

White-throated NT       yes                     yes                     yes
        (Juv)                   yes                     brown           yes
Silver-backed NT                yes                     yes                     
Brown-backed NT no                      brown           Dk brown
Purple NT                       no                      no                      

Michael Tarburton



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