Sunday, 18 February 2018

Pigeon Guillemot: columba and snowi

Wonders will never cease! The Habomai boat trip I booked actually sailed! This was the first time I made it out on either this or the Ochiishi boat. Waves or ice in winter and fog in summer have always conspired to keep me firmly onshore. The only complaint I have about this trip is that two hours is way too short. But there are more days than sausages, as my Hungarian companions might have told me.

The conditions were fairly calm which made spotting alcids so much the easier and this turned out to be my first opportunity to see a couple of species up close. I've managed pretty good harbour views of Spectacled Guillemot and Ancient Murrelet but Least Auklet and Pigeon Guillemot have always been well off shore. I was particularly pleased to have comparative views of two races of Pigeon Guillemot so in the unlikely event of 'Kuril' Guillemot being split I have my insurance at the ready.

The sea may have been been in gentle mood but it was still difficult to get good shots of the alcids as they were frequently obscured by even that slight swell and balance, or lack of it, meant sharp focus on flying birds was hit or miss, mainly the latter. Nothing would make me happier than to have the chance to practise in the hope of making perfect... but realistically that isn't going to happen.

Cepphus columba columba (or kaiurka?) with obvious and extensive white in the wing coverts. Note the distinct but narrow eye ring with faint pale eye line to the rear, echoing Spectacled. This is said to be a feature of snowi but is far more distinct on this bird than the snowi I saw.

The same bird as above.

Cepphus columba snowi. The flank feathers cover most of the wing, nevertheless white coverts would have been visible on columba. Rather than echoing Spectacled's face pattern, this bird has a pale decurved 'supercillium'.

The same bird as above though lighting makes it appear substantially different.

The same (presumed) columba as in the first images. The white in the upperwing coverts is very eye-catching in the field as can be seen to better effect in the image below.

The same bird as above showing its very conspicuous white wing patch.

The same snowi taking off. There's no white to speak of in the upperwing on this view. Note it has a whitish hind 'supercillium' in a slightly different position to the comet's tail behind Spectacled's eye patch. There is no eye-ring whatsoever on this bird.

The same bird as above, again the supercillium is quite distinct.

The same bird more distantly. Faint restricted white coverts bars are actually more visible here, though no more conspicuous than the rump barring.

Another snowi, coverts tips are just visible. This bird does have a Spectacled-like eye ring and down-curved eye line.

Same bird as above. You can just make out a single coverts bar here, it's more obvious in the original image before resizing to post.

Spectacled Guillemot with typical bold eye patch.

The same bird as above with uniformly dark coverts.

A near breeding plumage Spectacled.

Wednesday, 7 February 2018

Slaty-backed Gull: variation in saddle shade

How many shades of Grey? Slaty-backs and Vegas milling around an outfall on a calm sea. This is not unlike one of those kids puzzles where you have to find the matching pair amongst all the similar looking alternatives. Only in this case there isn't a matching pair to be found.

I took the above shot in Mie early in March 2016, it was one of the rare days at the site that the sun and wind weren't trying to out-do each as the biggest obstacle to gulling. At the time I was intent on the two Slaty-backs (second and third from the right) and their differing saddle shade. It was only back home going through the images that I noticed the Vegas are doing their level best to express their individuality in this shot too.

On more than one occasion concerns have been voiced about the paleness of some potential Slaty-backed Gulls in Europe and North America. I've struggled to see the problem in images of the birds I've seen, more often than not I see perfectly normal saddle shade for Slaty-back from my Kansai perspective.

To me surprise goes in the opposite direction and every so often I come across a really dark Slaty-backed that stands out from the crowd and I wonder if this is what observers elsewhere expect to see from a vagrant. The vast majority of birds I see aren't so much darker than the dark end of the Vega spectrum. It's very doubtful you'd notice a 'local' Slaty-backed if quickly scanning a Vega flock, especially in sunny conditions. Perhaps observers coming to the region in winter and seeing Slaty-backed against a snowy background might get the impression of a much darker gull? Personally I never see the SBG/snow combination... fortunately. Coming back to the above image, if we could switch on the sun, at a glance the paler of the two SBGs probably wouldn't appear any darker than the Vega on the left as they turn and twist on the water.

Olsen's Gulls says there's "very little" geographical variation and cites King & Carey (1999) that northern populations tend to be larger and possibly have darker upperparts. If it's true that there's little Geographical variation, then the difference I see here must be down to individual variation and in that case I'd conclude that very dark birds are scarce to rare. I wonder whether observers further north would disagree?

This is the darker of the two Slaty-backs in the opening image and it's the only strikingly dark SBG I have images of from recent years apart from the gull last weekend. Older digiscoped images are of much lower quality.

This is a slightly lightened image of the same bird. In all these images, at differing angles, the most striking feature to me is how little contrast exists between the saddle and primaries.

The following images are all from last weekend and include my first 'super-dark' SBG of the winter. It's always worth bearing in mind Vega shows a wide range of saddle shade.

This is the local SBG gold standard, and the very distinct contrast between saddle and primaries is obvious. Images of gulls always don't always convey the reality of the observers' experience, it's often so difficult to judge shades of grey from images; different angles, different light conditions, birds compared with different individuals and so on. However this saddle/primary contrast is unequivocal and I think the clearest way to indicate the difference between the lighter- and darker-saddled birds. 

And another typical SBG.

The same SBG with a Vega. This SBG my be standard in appearance but it didn't seem the brightest SBG on the beach, it repeatedly brought its catch back to the same spot where the same Vega would steal it.

The same bird on its (rather pointless) hunt for shellfish.

Another SBG in flight, here looking slightly darker only as a result of the angle.

I was quite happily getting shots of typical Slaty-backs when way along the beach I spotted a 'black-backed' gull. This had to be a dark-end SBG; the other candidates would all be first records for Japan. So off I went, as fast as the softer sand higher up the beach would allow. The light was a tad bright by the time I got there and, if anything, even better to bring out the shades of grey.

Dark-saddled Slaty-backed Gull with Vegas (2 Feb 2018). These gulls are clearly blackish-backed whereas the standard birds are... well, slaty.

Again, from a different angle there's still little contrast between saddle and primaries.

A standard SBG (sub-adult) with the dark adult to the right. That's a Taimyr Gull in the background.

The typical sub-ad SBG on the left and a Vega on the right. This was as near perfect gulling light as you could wish for.

A more heavily cropped version with just the two Slaty-backs.

Monday, 5 February 2018

Mi-chan the Thayer's becomes a statistical irrelevance

For 10 years Mi-chan has winged her way south to winter on the Costa del Tsu, I say 'her' befitting the name but I don't know whether 'she' is female. For 10 years she has been the only game in town, a tick for anyone unable to make the long trip from Kansai to Choshi. And in return was affectionately dubbed with the Mi kanji of Mie prefecture. She's the only adult Thayer's I've ever seen. And she's an absolute stunner!

I had tried for years to find an adult Thayer's down here but in this part of the country hen's teeth are ten-a-penny by comparison. When I did finally connected with Mi-chan I was ecstatic and unlike repeat sightings of many rare birds the novelty never faded and every time I saw her I felt the same rush... Yes! Thayer's!!! Now, I don't for one moment imagine I'll be less excited to see such a fantastic gull at anytime in the future, it's just I'd already seen glaucoides kumlieni in Kansai. So wonderful as Mi-chan may have been, may still be, she has been reduced to a statistical irrelevance for me by the unfeeling red pen of the IOC.

Feel free to lump the Redpolls guys. And I'm not too fussed how many bars a Greenish Warbler has either, lump them as well if you must... but come on, the Thayer's? Seriously?!

Anyway, I went gulling in Mie last Friday and I spent all day on the beach. None of the usual fields ploughed or scrubby, no woodland edges, neither ponds nor riverbanks, no estuaries, no mudflats and definitely no sandbars. Much as I love gulling I'd never dedicated a whole day to the beach because the Tsu/Matsusaka coastal stretch has so much good habitat and attracts so many good birds; a day can never do it justice. That's without even considering the gull beach north of the city. But I was keen to look for Thayer's and whatever oddities the ever changing gull population might throw up.

I timed it to arrive around dawn before the tide began to drop and when I popped my head over the bank the beach was solid gulls in both directions. As the tide drops the loafing masses begin to stir and hunt shellfish in the surf but right now they formed a deep, white border along the high tide mark... which direction to walk? The advantage at high tide is the loafing flocks are quite approachable but it's difficult to check the majority not on the landward side of the gull-belt as the beach suddenly angles down steeply. Once they begin to hunt it's much easier to view all the birds but the downside is that if you do find something interesting it could be patrolling a three-kilometre stretch of beach meaning a lot of exercise legging it back and forth along the shore trying to keep up with it.

The morning was calm but sunny which is often the case here. The wind frequently picks up dramatically in the afternoon, not often to tripod toppling strength but sufficiently buffeting to render the scope next to useless. So as the morning progressed I was considering a midday move but the wind never picked up, cloud cover rolled in and the light was gull perfect. Great light, no wind and ideal timing with the tide (and on my day off), it's so rare for these things to coincide that I had to stay and it was well worth it. But I'm getting ahead of myself, back to the early morning and Thayer's... sorry, Iceland.

I walked south towards the area of beach, which in my experience, Mi-chan tends to hang out. And it wasn't long before scoping southwards I picked her up, a sore-thumb (sighs) Iceland way down the beach at the end of the line.

When I got down there doubts began to creep in. It was certainly a Thayer's... but was it Mi-chan?

I hadn't seen the bird for a year and winter markings might be a little different year by year but there was sufficient doubt to make checking this bird against last year's images the first stop when I got home. It turns out this is a different Thayer's. So are there now two Thayer's in Tsu or has Mi-chan handed on the batton?

Mi-chan the Thayer's becomes 'new bird' the Iceland