Woodpigeon and Starlings (22 March 2003)
Woodpigeon Columba palumbus is another species that can be tricky to age. Part of the problem is that we handle so few of them, so don't get the chance to become very familiar with the species; and they are such a strong bird - more than a handful - that it is not easy to look at the right tracts of feathers whilst still firmly restraining the bird. This week I mist-netted one in my garden from which I managed to take a few photographs.
The odd coverts, lighter-coloured and more frayed than the rest, indicate that it is age 5, hatched 2002.
Woodpigeons moult some of their primaries and secondaries in their first autumn of life, then suspend the moult during the winter and resume in spring. This bird had moulted its innermost four primaries and outermost two secondaries, a group of six adjacent flight-feathers in the middle of the wing. The 'new' feathers are darker grey and with almost no wear on their tips, whilst the 'old' feathers are more brownish in colour and a bit frayed. I could not photograph the whole wing in one go but the following three photos show:
(i) the six new feathers, with some of the old secondaries. Note the obvious difference in shape between the innermost primary (broad, square-ended) and the outermost secondary (much narrower and more rounded):
(ii) the ten primaries, with the moult limit not so obvious in this picture from the colour of the feathers, but the difference in shape and wear of the tips is clear:
(iii) and the moult limit in the secondaries:
I also suspect, from looking at this photograph, that the bird might have moulted its tertials - they look greyer than the brownish old secondaries - but I must admit that I didn't notice that with the bird in the hand and it was a struggle to photograph this much!
I said earlier in the year that I would probably return to the subject of Starlings Sturnus vulgaris. They are now becoming easier to sex by bill colour (as well as the females having the white ring in the eye), as the hormonal influence changes the base of the bill to blueish (males) or pinkish (females). The two head photos show adults of each sex ringed recently.
Finally, Starlings are not the easiest birds to age. As well as the length of the throat feathers, one of the characteristics that helps with ageing is the shape of the uppertail coverts. The two images below show an adult (6) male on the left, and a first-year (5) male on the right. The differences are quite subtle, but the adult feathers are more pointed than those of the first-year bird: this is, of course, the opposite way round to what we expect for most species and most feather shapes, with adults' feathers being rounder than the first-years'.