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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