Some weekends ago I stayed with some friends in Bernat's 'country house', that is surrounded by typical mediterranean forests and drylands, where I decided to set up some nets to catch something.
I had bet that we were going to catch about 15 birds, but already in the first netround we exceed this number. In total, we trapped 41 birds, that is not bad for a 'completely random place' in the middle of a really extensive and almost uniform habitat.
The most interesting bird to examine was an Eurasian Jay (Garrulus glandarius).
Ageing is always interesting, at least for me, because I've only handled a few. Look at this adult
that I trapped this summer (somewhere in the middle of the post). As in that bird, this one showed bright blue coverts with parallel and well-defined black bars. Also the distance between them is almost the same in every case.
|With the wing closed, is easy to assess the distance |
between bars and its 'quality'.
|Secondaries are also glossy black contrasting with primaries.|
|It had a really broad R5...|
Everything seems to fit with another adult!
|When I took this photo I remembered that juvenile Carrion Crows |
and Ravens usually have pink inside their mouth. I wonder if 1st-year
Jays also have this colour inside...
Following the 'Blue wings' title...
Some weeks ago I trapped this Kingfisher (Alcedo atthis)
. It was already ringed, with one of my rings.
As you can see, it's an obvious female. And as a good female, and with this greenish escapulars and mantle, it seemed initially first-year.
|Looking at the crown, there were apparently two|
generations of feathers.
|And the scapulars also had some more bluish feathers, |
that seemed to be moulted... These last two features are
good for a 1st-year.
|But feet were bright orange, with only a bit of black on |
tarsus, that fit with an adult out of the breeding season.
|Breast orange was also 'adult-type'...|
|The wing was really interesting. All primaries were really fresh and wing coverts very bluish. |
Adult-type secondaries are more pointed than juvenile's, as in this bird.
|But looking at the secondaries properly, I saw S3-S5. |
They are retained! These 3 feathers are less black, shorter, and slightly less pointed. In fact, inner SS are more pointed, and this is because the inner web is more angular, and more rounded in first-years.
|Usually I didn't look much at the tail, I find it a bit|
hard to assess properly. Nonetheless, this bird had only
one generation of rectrices.
Later, already at home, I checked the ring number in my database. I had ringed this bird in the same place in 20th May 2013, as a second-year
female (EURING 5). So, that bird did a postbreeding (her first one) arrested complete moult
. This would suggest that 2nd-year birds can be aged also in December, and therefore, as 3rd-years (EURING 7) in spring...! I'll try to catch more in the next days...
It's known that adult Kingfishers sometimes do an arrested postbreeding moult, and when this happen with second-years, we will be able to age them after this moult...
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