Nearly every year I manage to trap a Spotted Crake or two at my ringing site in Meijendel. Over the years I noticed a helpful ageing feature that I cannot find in the books on my shelf: feather wear. I wrote a note on ageing Spotted Crakes in summer and early autumn, that includes this feature. It should also be useful in the field! I hope it'll be helpful.
On 14 July I stumbled upon a calling Iberian Chiffchaff (ca 45th record) in my hometown The Hague. Since calling birds are probably overlooked in The Netherlands, I wrote a short note on their calls.
Upper and lower pic by Gerjon Gelling
Quite amazing that I was lucky enough to find two of these birds within 3 months! Ageing this bird turned out to be straightforward. In July juveniles are very fresh, while adults are completely worn and usually in their post-breeding moult - like this bird. So as expected (since a juvenile in July would be sensational), this was an adult bird.
On the 15th, I managed to get some shots, and my friend Gerjon got much better ones. This allowed us to have a better look at its plumage. Well, this bird wasn't very pretty! It was worn and moulting body (there was even bare skin visible on the throat) and wing feathers which, in passerines, are moulted symmetrically in both wings. See pic:
I count 5 visible primaries. The very short P1 cannot be seen in this shot. The shot is just not good enough te be entirely sure, but it seems to be missing 4 primaries. P? is a growing feather and I don't know which one it is (since the inner one is moulted first, this could be P10). There's also a growing inner secondary. So it's hard to judge what's precisely going on, and it's impossible to see if this bird is perhaps in its 2nd cy (see this article), but it's moulting remiges, allright. Hence, this can never be a juvenile!
Btw, here's a typical call of the bird (14 July 2017):
On 21 June Gijsbert Twigt and I trapped a Spotted Redshank in Meijendel, Wassenaar - the first one ever to be ringed at the site, where ringing started back in 1927.
This bird is obviously in sum plum and given the time of year, it's never gonna be a juvenile of course.
Note the fairly fresh primaries. 2nd calendar year (cy) birds have very worn primaries, so this bird must be older.
It has of course a lot of white fringes on the underparts, but an interesting feature to sex birds are the central undertail coverts.
In spring males these are blackish, whereas they are white in females. So this is a female! This must be nearly impossible to see (well) in the field.
So this bird is an adult (> 2cy) female. Not surprising given the time of year: this female was already on autumn migration at the end of June. The females lay eggs on the Scandinavian and Russian tundra, but leave before the eggs hatch. The males stay behind to take care of the brood.