Thursday 11 October 2012

Gulling


Today I thought I would kill 3 birds with one stone. I decided to cycle down to the waterfront in Oslo and by doing so would (1) get some desperately needed exercise, (2) hopefully add Razorbill (alke) to my Oslo year list and (3) have a chance to put my new found enthusiasm for large gulls to the test.
As far as the exercise goes I confirmed how dire things are. On a similar ride to that Mrs Oslo Birder takes to work I was overtaken by ladies old enough to be my mother (no offence meant mum) and had legs like jelly when I got home.
As far as the Razorbill goes I succeeded. In the enclosed bay at Bispevika seven Guillemots (lomvi) and a single Razorbill were actively feeding. There were obviously numbers of small fish as three Cormorants were also successfully fishing here. One Guillemot was fishing under a jetty and I could actually see it under water right under my feet but failed to get any photos. Additionally 2 Razorbills were on the sea offshore from the Opera building. During the large Guillemot influx of a month ago I didn’t see a single Razorbill but as numbers return to more normal levels (it seems that the vast majority of Guillemots have successfully returned to open sea rather than perished) there are now a few Razorbills appearing. Razorbill takes my Oslo year list to 148 which is only two short of the highest published list. I have not consciously chased this list until now but will probably make an effort in the remaining months to fill some obvious holes.
Guillemots (lomvi)
Razorbills (alke)

So how did I score on my third objective? Well, I can confirm that gulls are difficult, complex and frustrating but I can also report that I may actually start to find them interesting – they are definitely challenging.
I had three particular birds of interest. At the risk of appearing foolish I will present these birds and my thoughts and would appreciate any feedback. After spending hours looking at ID guides and trawling the net it is clear to me that the only way to crack these birds is experience and to get out there. Maybe I'll become a larophile afterall. CLICK ON THE PICTURES to see them in higher resolution.

Gull 1.
This bird is I believe a 1cy Lesser Black-backed Gull (sildemåke) due to dark tertials with just pale white borders and greater coverts. However on the open wing it has a noticeable pale panel on the inner primaries which looks too extreme for LBBG. I have considered Yellow-legged Gull but don't get the head and bill shape to fit and don't think I can detect any moult in the scapulars although the upper scapulars and mantle do look a lot paler. EDIT: probably just a Herring Gull.


in this out og focus picture there appears to be a very pale window on the inner primaries

In this focused picture the pale window although hard to see looks less striking

Have some of the mantle and scapulars been moulted? Certainly look pale for a LBBG



Gull 2.
I found this whilst trying to relocate Gull 1 which had flown from Bispevika to the fresh water lake at Middelalderparken where many gulls bathe. It never came that close hence the pictures are rather poor.
This bird had a very different jizz to the other large gulls although this could also change depending on angle. It appeared longer bodied than Herring Gulls and when sat on the water had more the shape of a small gull.  The head shape with a flat head also differed from surrounding birds. In the flight shots you can also see the hanging belly to the rear of the legs. I have a definite Caspian Gull (kaspimåke) feel about the bird but don’t know if everything ties in. The bill isn’t of the longest variety and perhaps isn’t parallel-edged enough but there is variation. Also the underwing looks very pale in some pictures but dark in another (significantly different lighting between the pictures). There is very little contrast in the closed wing when it is sitting on the water and the uperparts seem far too pale but I believe that the coverts are mostly hidden by the scapulars. Looking at the pictures Great Black-backed Gull also seems a possibility and the primary projection beyond the tail looks short but in the field I never considered this as the gull was no larger than accompanying Herring Gulls and jizz wise resembled a small gull as it sat on the water.
the jizz of this bird seemed wrong for Herring Gull



underwing maybe looking too dark although also in shadow

In this picture undering looks very pale and you can see the heavy back end





Gull 3
This bird is so pale that I previously would have suspected it to be a hybrid between Herring (gråmåke) and Glaucous Gull (polarmåke). However similar birds seem to be relatively frequent in the Oslofjord (definitely far more frequent than pure Glaucous Gulls) and also turn up early (such as this bird) such that they appear to just be within the variation of Herring Gulls. Note though the jizz of this bird which I feel has a distinct Glaucous feel to it.
very pale primaries and tertials on this Herring Gull


The pale Herring Gull to the right with a more normal 1cy Herring Gull to the left


There were also a number of 1cy gulls which I have to admit to struggling to ID as either Herring or Lesser Black-backed (I have been in and edited this blog post a number of times and will probably end up making further edits!). Amongst the adult gulls all the Lesser Black-back Backs have already left and there were only adult Herring Gulls but amongst the small number of 1cy birds there were possibly some juvenile LBBGulls left - but it isn't easy.
1cy Herring Gull

2cy Herring Gull

advanced 2cy Herring Gull or retarded 3cy?

presumed 1cy LBBG juvenile (1cy) Herring Gull

presumed 1cy LBBG but are the tertials too well marked? 1cy Herring Gull. Some 1st winter mantle feathers are already present

Juvenile Herring Gull

Is this a juvenile LBBG or just a dark juvenile Herring Gull?

1st winter (1cy) Herring Gull at the front and the same dark gull behind as in above picture
Also by the Opera were single ringed Greylag Goose (grågås) and Pink-footed Goose (kortnebbgås). The Pink-footed was very tame and is a juvenile. Rather than it being of captive origin I assume that it has lost contact with its flock on their way over Oslo and ended up here alongside a Greylag Goose. It did appear a little sickly which could explain why it lost contact with its kin. The ring was the work of the local ringing group who found this bird a few days ago.
Pink-footed Goose (kortnebbgås) by the Opera


3 comments:

  1. Really nice with more gulling people in Oslo! When it comes to your photos, the first gull is a Herring. Mainly because of pale window (never so evolved in LBBG) and moult in scalpulars (yes it have moulted a lot actually). The 3.bird is an Herring. The 2. is also most likely a Herring, but maybe you should send it to someone... Herring vs Lesser Black backed are sometimes difficult. In Oslo now there are very few LBBG left (1 in 30 Herring or so) so maybe some of them are ID wrong? :)

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  2. Since you have edited the last comment isn't that important... :) All 1cy large gulls are similar (well... quite), and when you think you have control some individual comes in and ruins it. Photo 22 was earlier today marked as LBBG, but is changed to Herring. Looks like a LBBG to me. Small looking gull with dark on greater coverts. 25 and 26 shows Herring Gulls. Inside what would go for normal variation.

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    1. Hi Sindre, thanks for your good comments and indeed it does feel good to finally start enjoying (?) gulls. I have also asked Stein E for his comments and he agrees that number 2 is also a Herring Gull. With regards the bird in picture 22 I will stick to it being a Herrings as when I fine study the bird (and I have some other pictures of it) then I don't really see anything to distinguish it from the other Herring Gulls. Stein also agrees it is a Herring and of course has far more technical/detailed arguments than myself.

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