NLRG was formed in 1957 to help in the study of birds in the Lancaster and District Birdwatching Society area. There are currently 12 active ringers. Species currently being studied include: Pied Flycatcher, Bearded Tit, Sand Martin, Twite, Goosander, Oystercatcher and Grey Wagtail. Migration has been studied for 28 years at Heysham. We welcome anyone who wants to observe, help or perhaps wish to become a ringer. Photo: A Heysham-ringed Twite on the Mull of Kintyre (thanks to Eddie Maguire)

Friday, 31 October 2008

Identification problem?

Caught today.
The yellow bill and unmarked throat indicates that this is a Twite and not a Linnet. So far so good. But is it male or female? As we can't see the rump (pink in a male) the wing should give a clue. On males the "white on the inner visible 5mm of the outer webs of the 7th to 9th primaries reaches the shafts, or is usually less than 0.5mm from" (Svennson) whereas on a female the "dark zone" is 0.5mm wide or more and generally half the width of the webs. Using this criterion the bird should be a male. But, in fact, the rump had no pink in it at all. The end of the tail feathers are obscured so you'll have to take my word for it that they were pointed and that it was therefore a young bird. A final mystery is how the heck does Alan keep his fingernails so clean when out ringing? Posted by Jean.

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