Thursday 8 May 2014

Isabelline Shrike, Hegurajima

My stuck-at-home vacation was becoming a little boring and when the marine forecast was indicating 20-30Kt winds from the Yellow Sea to Japan on the 4th and 5th and the satellite images indicating the origin from much further west plus a slow moving front spanning the Japan Sea, creating a belt of rain working its way up the coast, I though Hegurajima was the place to be on the morning of the 6th.

A day-trip to Hegura actually means just 4.5 hours on the island, between docking at 10:30 and departure at 15:00, a brief look round the island at arguably the least productive time of day. The ferry had been cancelled because of high seas the previous day and was full of birders eager to make up for lost time. I don't normally go to Hegura in spring and I always thought there to be fewer cancellations in spring but I understand there have been plenty of disappointed people turning up at the harbour this year. It's a long drive for so little birding but for a long time I've really wanted to visit the tip of the Noto Peninsular, it looks very interesting on satellite maps, and this mini-trip gave me the chance. While it's no Hegura, it is actually very good and would probably make an excellent alternative in the event of the ferry not going.

I learnt from the other passengers that there were no major rarities already known to be on the island allowing me the luxury of going wherever I pleased rather than spending my time looking for other people's birds. As it turned out I didn't have far to look as the Shrike was waiting in the harbour. My fellow passengers had all rushed off to dump their gear in their respective minshyuku and as the only day-tripper I was left alone to find the bird. Luckily I did find it then, it seemed very unsettled and presumably new-in. It quickly moved from it original location in four hops to disappear into trees about 200 metres away. In fact discovery to disappearance probably took no more than three or four minutes - maybe it was more but it seemed no more than that. A camera malfunction initially followed by my over-excited trembling also played their part in the resulting paucity of images, saddly the following are the only reasonable ones I could get.

First impressions; though it's a really pale bird I expected it to be a Brown Shrike when I first picked it up.

Through binoculars it looked far more interesting. The first feature to catch my eye was the white patch in the base of the primaries, I believe some Brown can show white but I don't think it's ever as prominent as on this bird. The black mask put it in male territory, but why the white lores? My hands were already shaking by this time. The colours don't look great in these images but the fore-crown is sandy while the hind-crown and nape are sandy-grey. The rest of the upperparts are greyish-sandy, thus the nape is greyest and contrasts with both adjoining areas. In the two images above the outer tail feather is exposed and is ornage for its full length there fore there is a clear contrast here between it and the longer central feather which darken towards the tip (better seen in the following two shots).

Unfortunately flight shots were beyond me the first time it flew the impression was of an incredibly pale sandy bird with a bright orange tail when fanned. By far the most outstanding feature in flight.

The light at a different angle here. Black extends in front of the eye as a narrow point, black also borders the base of the uppermandible and spikes inward a little from the gape. Thus there's a diagonal white slash across the lores. The central tail feathers darken slightly from about mid-point to produce dark tips. Not really visible here, the uppertail coverts and rump are less orange than the tail but brighter than the back.

As the face and forewing are shaded it's easier to see the very narrow white supercillium before the eye flaring up slightly behind the eye. Also in this shot you might just see (easy in the original) the contrast between the warmer fore-crown and greyer hind-crown. Both median and greater coverts are mainly blackish, or at least very dark, but this is largely masked by pale sandy fringes. The uppermost tertial is sandy with an even paler fringe but longer tertials are blackish with pale fringes.

The only two people I showed my pictures to on the island dismissed the idea of Isabelline with both Bull-headed and Brown being suggested as the true identity. Personally it looks a perfectly good male isabellinus Isabelline Shrike to me and made the decision to do a Hegura day trip on spec a very good one.

I'll write more about the other birds on the island and along the peninsular tomorrow, but for now I need to get some sleep before an early start at work tomorrow.

After researching Isabelline on line I discovered the type specimen was misidentified and the trinominal isabellinus rightly should be applied to "Daurian" Shrike so just for clarity this bird is of the north west China population "Chinese" Shrike.

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