Rausu and Notsuke

From the Blakiston's Fish Owl atYoroushi Onsen we cut across to the coast to head up to Rausu and the next iconic Hokkaido sight, the flocks of eagles around Rause harbour.


The eagles were the main target and though it would have been good to connect with the likes of the returning Bufflehead, the local wintering Ravens or anything else of interest we moved soon moved south to the Notsuke Peninsula once we'd had good views of the eagles and checked the various (largely empty) harbours.

Imagine this on your doorstep.

The usual birds were in the harbours but from the Kansai perspective Harlequin Duck, Glaucous-winged and Glaucous Gulls were the pick.

Harlequins



Glaucous-winged Gulls

Juvenile Glaucous takes some beating...

The first birds we saw on Notsuke were Snow Buntings but it was really difficult to get decent shots because they were quite flighty and the grass stems meant some were always out of focus. It was only after going through the images at home that I realised Snow Bunting was a photograph tick!

In late afternoon hundreds of Sika Deer were coming out into the open along the peninsula.

I've never been to Lake Biwa when there wasn't a long line of photographers' cars and ranks of cameras at the ready to capture 'our' Steller's every move. It almost seems sinful to have a solitary Steller's all to yourself.

A hybrid gull... but what parentage?

The same day I saw the recent adult Thayer's I also came across this second-winter gull. I hadn't seen much of interest up to that point and this gull was the judges overwhelming choice for bird-of-the-day if it hadn't been for the Thayer's appearing at the death and pipping it to the accolade.


I haven't seen a hybrid quite like this before and I'm curious about its parentage, for each potential combination there is something that doesn't quite sit comfortably. The only thing I would put money on, is that Glaucous-winged is involved. Money, but not the house. And if my arm were twisted, I'd plump for Vega as the other progenitor.

So here's the bird. The smallish size, to an extent structure and aspects of the plumage could be highly suggestive of second-winter Thayer's. The head looks fairly rounded in this image and notice the white far-wing.

Another angle and the head looks much heavier, as is the bill towards the tip, more of a Glaucous-winged feel than Slaty-backed. The body was only about the size of a smallish Vega.

Glaucous-winged x Slaty-backed is a logical choice in Japan but they both are relatively short-winged, typically with a deep-based and blunt-tipped primary projection but this bird is distinctly long-winged and that combination is highly unlikely to produce it. There isn't much overlap in breeding ranges of Glaucous-winged and Vega which may explain why I've never (knowingly) seen that hybrid. Vega x Slaty-backed, which I have seen, is more likely because of a greater area of sympatry according to range maps but I don't think there's much to suggest Slaty-backed about this gull.

In this view the stronger light means the upperside of the primaries looks much greyer compared to the previous images, while shadow creates the darker underside.

The tail is still quite solidly dark and there's a ghost of a p10 mirror.

The upperside of the primaries has a Glaucous-winged feel with a clear difference between inner and outer webs.

If it is a Glaucous-winged hybrid it might even be worth considering a New World combination, there seem to be plenty of hybrids across the water and Glaucous-winged x American Herring Gull ranges have significant overlap. This could account for the longer-winged appearance but surely such a hybrid would have a paler saddle and so seems a non-starter. The larger mirror of the underside of p10 is just visible on the upperside.

A few interesting recent gulls

This is just a quick post to show some of the gulls I thought interesting (for one reason or another) recently. I have mountains of gull images that never see the the light of day, in fact there are files full of images I haven't got round to checking at since the day I took them! Most of these gulls I saw during my last two visits (January) to Mie.

A presumed female Taimyr judging by size. This gull really caught the eye because not many have such yellow legs at this time of year. The moult is at the faster end of the progress scale but not unusual, a couple of other birds had p8 as the longest new feather. Towards the other end of the scale I noticed one gull that hadn't dropped its old p8 yet. 

P8 effectively black to the coverts, it's just becoming blackish-grey proximally though this probably wouldn't be obvious at a any distance. P7 is also extensively black and the black notch on p4 is also fairly standard.

A remarkably small p10 apical spot which at this moment is twinning a tiny p9 mirror.

It's a smallish gull, here with Vegas, I think it's going to have very long primary projection in relation to the rather short tail length when the primaries are fully grown.

With a first-winter Taimyr in the background. Thoughts of possible barabensis crossed my mind at the time but being realistic the fresh primaries due to much later and ongoing moult plus the lack of expected bill markings rule that out. 

The same first-winter Taimyr. The narrow pale tips have worn of the tertails, and fringes from the inner greater coverts, creating a very uniform appearance.

Another adult Taimyr, this still with three retained outer primaries. In the field the legs were pinkish overall as they seem in this image but less so than Vega, on closer inspection however the back of the knee was distinctly yellow and the rear of the tibia only slightly less so. This is closer to the norm at this time of year rather than the bright yellow of the earlier bird.

Mongolian Gull? Here as part of the flock and a couple of heavily cropped individual shots below.

A white head in the flock is always worth checking but a number of Vega can stay surprisingly white-headed through winter. However this bird's structure and extensive black towards the bases of the primaries all looked good for Mongolian (I didn't get flight views) so I was really taken aback to see it hadn't completed its primary moult. All but the very earliest arrivals in November seem to have already completed their moult, perhaps not unexpected in a southern breeder. This bird was even behind the vast majority of Vega in its timing. I still think it is a Mongolian, but one with a noteworthy late moult. 

Vega with a white band through the sub-terminal black of the tail are very scarce rather than rare but this bird wins first prize for style; I've never seen such a well banded tail on any other gull. As for it being a pure Vega... well, it's at the whiter end of the spectrum but nothing to write home about, the oddest features (other than the tail) are its very short legs and small size.



If I had that tail pattern, I'd want to keep it into maturity!

There's nothing in the plumage to indicate it's a hybrid as far as I can see, it's simply a very distinctively patterned bird.

For me this is a particularly dark Slaty-backed, I see a small number like this but they aren't the norm in this region at least.

The same bird in the foreground later in the day. The other Slaty-backed has a more typical saddle colour, in this region certainly. 

This was another dark bird last winter, in flight there was almost no contrast between the outer primaries and the rest of the wing. 

First-winter Slaty-backs show enormous variation but this gull looks good for Glaucous-winged, a bird I rarely see in Kansai.