• Vincent

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):

#IberianChiffchaff #calls #ageing #Phyloscopusibericus #moult

  • Vincent

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.

#ageing #sexing #SpottedRedshank

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  • Vincent

Spring 2016 was mind-blowing: good migration, loads of rarities and a few nice influxes due to seemingly never ending easterlies. But this year's spring was rather odd. In general it was kinda bleak. But I had a fantastic spring myself when it comes down to finding rare birds.

A Blue Rock Thrush on the island of Vlieland was an exciting twitch (2nd Dutch record, new bird for my Dutch list), for the 2nd year in a row I only heard a Moustached Warbler (2nd record), but basically I'd found nothing myself (save a few white winged gulls) until I stumbled upon a calling (and later on singing) Iberian Chiffchaff on the island of Texel at the end of April (c. 43th record), twitched by those birders already on the island. A few days later I saw a lovely 2nd cy male Pallid Harrier, but this was probably the same bird that flew past there the day before.

Less than two weeks later, me and my birding mate Wouter van der Ham found a Black-winged Kite while driving 90 km/h (ca 21st record). This species might very well be the next Pallid Harrier: once a mega, but rapidly increasing. There have been no less than 17-18 records between 2009 and spring 2017. So in a way this find was an accident waiting to happen! We saw it for a whole 90 seconds... It was picked up by 7 other birders in the direction we lost it, before it disappeared for good.

Black-winged Kite, Ouddorp, Zuid-Holland, 11 May 2017 (Wouter van der Ham)

In the mean time a male Seebohms Wheatear popped up in my hometown The Hague – a first for Europe away from the Mediterranean. And a lifer - I don't get to see many in Holland! Since I was one of the few birders with access to the area, I shared mind blowing views with six others. The twitching crowd experienced a lot more stress. They didn't see it till the dying hours of the day and they certainly didn't have views we had. Lucky us.

We hadn't mentally processed the mega wheatear when Gerjon found a singing Melodious Warbler near my favourite vis mig spot De Vulkaan – another first for the The Hague area, though this one was long-awaited. I was the first one to twitch it – and the last one. It miraculously fell silent, never to be seen again.

Early June brought a lovely Greenish Warbler right next to my house. My third new self found bird within little over a month! And again a new bird for The Hague (also long-awaited), which is really good since this is the city with the longest bird list in The Netherlands. When I heard it from my living room while getting the children ready for school, I actually thought my phone was playing the song in my pocket. Can you imagine my face when I found out my sound player wasn't accidentally turned on? Great bird for the house list!

So I found three really good birds, while basically I found jack all otherwise and migration was slow on most days. But the rare ones have been good to me. Really good.

Spotted Redshank, adult female, Meijendel, Wassenaar, The Netherlands, 21 June 2017

Finally I settled an old bill at my ringing site: a lovely adult female Spotted Redshank was long over due, but therefore even more appreciated. The first one ever to be ringed in Meijendel, where ringing started back in 1927! But even though it was still June, this bird basically announced autumn. In June, the females are already on autumn migrating. They leave the males behind to incubate and keep an eye on the chicks. So the end of spring was in fact a great start of autumn. Can't wait for all those autumn birds. Autumn, bring it on ;-)

#IberianChiffchaff #SeebohmsWheatear #rarities #BlackwingedKite #GreenshWarbler #BlueRockThrush #MelodiousWarbler

Little Bunting
The most interesting thing about this chapter is the sexing of birds. This could be done on the basis of lateral crown stripe: a new feature for me. Because of overlap between adult females and young males, birds should first be aged. The authors emphasize that this is their vision, and not necessarily the final answer to this matter. I found one in the field in October (Figure 4-5) of which I took reasonable pictures. The very rounded tail feathers look adult, as do the tertials and large coverts. The lateral crown stripe appears to be jet black and is separated from other feathers, such as the greyer back of the head. The orange-red crown stripe really stands out. Conclusion: according to this book this must be an adult male! The deep brown-red cheek - a variable feature according to this book - also fits that. So it works then? Well… how useful this really is, remains the question: based on this book I would label two "females" in Shirihai & Svensson (p546 both top right and bottom right) as males! The caption of one of these even mentions "safely identified as a female" because it has a relatively dull plumage for an adult bird. But is also has a jet black, strongly separated lateral crown stripe! The bird at the bottom right even has a pretty deeply coloured cheek, which I would be happy to call a male. Is this due to different insights, and if so, who should I believe? Or am I not interpreting this correctly? In any case, it is fascinating!

© 2018 by Vincent van der Spek