• Vincent

Bijgewerkt: 15 mrt 2020


Recently, a British rarity committee member asked how we deal with ‘Russian Jackdaws’ (ssp. soemmerringii) in the Netherlands. Incredibly, a day later I saw my best candidate in years. I didn’t have any birding equipment on me, so I had to use my phone to photograph it.



The commonly accepted (assumed?) situation in the Netherlands is that the dark ssp. spermologus is common year round*, that ‘Nordic Jackdaw’ (ssp. monedula) is a migrant and winterer (proven by rings) and that 'Russian Jackdaw' (soemmerringii) is a (very) scarce winterer.


ID challenges The problem is that Jackdaw variation is clinal and the ID is often problematic. There are intergration zones in Eastern Europe, and there's huge individual variation within populations (e.g. only half of the Russian Jackdaws have these long white neck marks; Shirihai & Svensson, 2018). So the dividing line between some individual Nordic and Russian Jackdaws is thin – very thin.


The best sources on the matter are probably Offereins (2003) and HWBP (Shirihai & Svensson, 2018), though they are confusingly contradicting at times. More on that later.


The return

A week later I returned to the site prepared. I conquered the storm and the dark clouds and managed to see the bird for a whole 3 minutes before it was flushed by a dog. It looked so dark, with the white in the neck so prominent, that I figured it was a Russian. Ok, I made some critical remarks, but still: I was too quick on the draw...

The return #2

A couple of days later I went back once more to observe and photograph it in better light conditions. I quickly found the bird. And the doubts kicked in immediately.

There are no moult limits, so this is an adult. But this is of no use for the ID. At least in soemmerringii the amount of white in the neck is not age-related (Shirihai & Svensson, 2018).


Overall the bird looked much greyer than during the dark weather earlier that week. Shoot! On a wanderer from the east I want to see nearly black underparts, as described by Offereins (2003) for 'classic' (extreme?) Russians. Contradiction #1: Shirihai and Svensson (2018) don't mention this. They even write: "[soemmerringii] has dark grey rather than near-black underparts (thus close to monedula)." ??? Confusing!


The underparts were more mottled than I noted before (one of my initial 'critical remarks'): a 'Nordic' feature according to Offereins (2003). Contradiction #2: again this is not mentioned by Shirihai & Svensson (2018).


Intriguingly a bird from Finland credited as a presumed soemmerrengii in HWPB looks pretty similar. Its ID is based on the 'slightly paler grey on head' and 'distinctly whiter half collar'. But Shirihai & Svensson (2018) also add: "much individual variation, and extremes of monedula can be very similar". 


It's indeed not dissimilar to birds I've seen in soemmerringii country. Check this one from SE Bulgaria (2011) and note the similarity of the grey and - yes - strongly mottled underparts. The main difference is that the Bulgarian bird has somewhat scalloped upperparts - a feature Shirihai & Svensson (2018) do and Offereins doesn't mention for Russian. And in fact it has a somewhat less white collar:

So my bird definitely wouldn't stand out as something odd within the breeding range of soemmerringii. But a more prominently marked Nordic cannot be excluded, not on current knowledge anyway, and since these are default the tentative ID should probably be: presumed (extreme?) Nordic / possible Russian


Now what? The two sources mentioned above fully acknowledge the problematic ID (cline, integration, individual variation). They are contradicting on some points. The thing is: pics in these articles are mainly from wintering birds, which IMHO makes their ID rather tentative. So who's gonna make 100s of shots of soemmerringii wintering within within their eastern breeding ranges?  

* PS Please note that Shirihai & Svensson (2018) mention that Dutch birds are probably best included in monedula instead of spermologus. However, a pic from Holland in the species account is nonetheless labelled as spermologus! It only adds to the confusion and probably perfectly reflects the clinal variation.


References

Offereins, R. 2003. Identification of eastern subspecies of Western Jackdaw and occurrence in the Netherlands. Dutch Birding 25: 209-220


Shirihai, H. & L. Svensson. 2018. Handbook of Western Palearctic Birds. Helm, London.

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  • Vincent

Sound track advice: Stormy weather - Billie Holiday

I’ve always considered myself a birder with a camera, rather than a bird photographer. What I do is functional, not aesthetic. I’m not particularly gifted in this department, nor am I interested in learning all about camera settings.

But once in a while even an amateur like me makes a decent picture: for the first time one of my shots made it to the cover of a magazine

Figure 1. Cover of Dutch Birding 41:5 with my European Storm-petrel picture

This European Storm-petrel was photographed on 12 August 2019 during one of Paul Connaughan’s Co. Cork pelagics. I planned to go out at the ocean four times, but nearly two weeks of continuous stormy weather saw my ambitions go up in smoke. One trip was all I got, but cracking views of Stormies washed away some of my disappointment.

In the Netherlands Stormies are rare: despite I live along the coast, I’ve only seen them on five days, the last time as long ago as 2010. And though I’ve seen some pretty well, it was nothing like this (a bit shaky, so don't get seasick):

European Storm-petrels, off Baltimore, Co. Cork, Ireland, 12 August 2019

I was curious to find out how to age these things. This bird is super fresh, crisp really. There’s no wear or moult whatsoever. The outer primary is rather pointed, not rounded. This all points towards a young bird.

Figure 2. European Storm-petrel, first calendar-year male, off Baltimore, Co. Cork, Ireland, 12 August 2019

I never knew you can also sex them. According to Baker (2016), males have extensive white on the underwing (with white medium coverts and white edges to the outer greaters), but apparently this only works for adults.

I also photographed this youngster that has less white on the underwing:

It makes me wonder if the more extreme birds could be males anyway. But sex: undertermined.

So did I make a decent photograph? I did! But still: functional!

References Demongin (2016) Baker (2016)

#ageing #sexing #EuropeanStormpetrel #DutchBirding

  • Vincent

​​When the ladies from bird hospital De Wulp sent me the shots of the Grey-cheeked Thrush taken into care last year, it really knocked me off my feet for a few seconds. But when Rinse and I received this video mid-July we were equally shocked:

(video by Sharon Lexmond / vogelopvang De Wulp)

Black Woodpeckers colonised the country around 1915 and reached the western part of the Netherlands half a century ago (my father actually saw one of the first ones on my local patch in Meijendel). A small breeding population established in the dunes – only to disappear again in the 1990s, correlated to the rise of the Northern Goshawk. I have only ever seen one in my province (Zuid-Holland). In 2001 we actually thought they had already been wiped out, so our sighting felt like we witnessed the arrival of a big black monster from the Upside Down, such was the surprise. We celebrated like we just found a national mega.

So now, 18 years on, one may really wonder: what on earth was this thing doing here? Well, as it turned out the injured bird was picked up by a truck driver in the SE of the country, within the breeding range of the species. The driver took it home and brought it to the nearest bird hospital he knew. It recovered well from its wing fracture over the next couple of weeks.

The red cap obviously makes this a male. Baker (2016) doesn't cover this species, Demongin (2016) only briefly and on Javier Blasco Zumeta’s brilliant website this is one of the few largely incomplete documents, so ageing it was interesting.

The bird was actively moulting lesser and medium coverts, as well as feathers on the upperparts, head and in the tail. The old coverts were brown-black, whereas the new ones were ink to shiny black, forming an obvious contrast. We figured this was a contrast between juvenile and adult feathers, which was later confirmed by Cramp & Simmons (1985). So a 1st calendar year bird it was!

Just look at the moult of the cap, and how the juvenile feathers are orange red and the new adult-type ones are almost crimson.

Early August it was successfully released at an appropriate site within its breeding range:

(by Sharon Lexmond / Vogelopvang De Wulp)

So everybody happy!

Once again many thanks to Sharon and Lizzy @ De Wulp!

#BlackWoodpecker #moult #ageing #sexing

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Sonagram 1. Drie roepjes van Bruine Boszanger. De typische v-structuur is hier goed te zien, en soms (linker roepje) is er een kleinere v zichtbaar binnenin de grote v. De roep is duidelijke hellend naar links. Opnamen: Thijs Fijen.

© 2018 by Vincent van der Spek