I used to find the literature very confusing with regard to the status of albus Japan. However as I've never had more than two sightings of albus per winter, and there have been blank years too, it's most definitely a scarce winter visitor to Japan, and if it breeds I'd speculate that such instances are rare. Or in parts of the country I don't normally visit. I do also get the odd spring migrant on my regular trips to Mishima in the first week of May but this bird on May 26 is by far my latest sighting and because albus are so obvious I really don't think I've overlooked any.
Winter birds stand out because of their huge size and bulk of course, even lone birds tend to catch the eye, but this bird was even more obvious due to its yellow bill when all the modestus have had their completely black bill of the breeding season, and at close enough range beautifully offset by blue lores.
This bird is not only of interest to me because it's the latest I've come across but also because of that yellow bill. My understanding of albus is that it should also be black-billed in breeding condition or with a yellowish base, perhaps being out of its normal range has delayed the change but that's hard to reconcile with splendid set of breeding aigrettes, the lores which are more extensively green than in winter and the leg colour; pink tibia and a deeper rosy-pink tarsus. So I've gone through my older images checking as far as I'm able how bill and bare part colours change. Those of modestus seem fairly consistent in timing and appearance but my small sample of albus shows more variation. Is it possible that young adults don't acquire a black bill? Then why don't young adult modestus also have paler bills. Is it possible eastern albus less frequently acquire black bills when breeding? Before I get side-tracked into barepart variation, I'll just show the images of this splendid bird.
|May 26: the latest date I've encountered albus in Japan.|
|There were three modestus on the same area of fields but none came close to the albus for a comparative size shot. Even at long range the black bill and legs are obvious, I'm yet to see a yellow-billed modestus in May.|
|The albus dropping in a little closer. It was quite mobile, frequently flying from field to field, plus we saw it later in the morning about 3km from the original location.|
|3 May 2010, Mishima. The size difference looks so great it's hard to credit they are both Great White Egrets.|
|15 January 2012, Lake Biwa. The yellow legs of the albus are easy to see in this digiscoped image. The difference in bulk is obvious but the overall size difference is less striking than with the previous two, or the recent bird and modestus.|
|So to immediately prove myself wrong, here's a modestus (18 October 2014, Kyoto) with extensive green on the lores. It seems too late to be a remnant of breeding colouration.|
|A typical non-breeding modestus (December 29) in Kyushu, with lores concolourous with bill except for a hint of green around the eye.|
|An albus on the same day and in the same spot as the previous bird, this with partially green lores, more extensive and prominent than seems the rule with modestus.|
|Modestus (4 March 2012) in Kyoyo city. This greyish, lets call it lack of colour, across the lores isn't unusual and is similar to the greyish lack of colour that is often present on the legs.|
|This albus over-wintered (Lake Biwa, 2 February 2014), it had a narrow black line up the centre of the tibiae.|
|A two-albus month (25 February 2012, Hyogo). This was a much yellower-legged bird.|
|An albus in Shikoku 2 March 2014, a local birder told me that winter had been exceptional and that there had been two or three birds in the area. The visible lore is extensively green, the leg colour is typical and never seen on modestus.|
|A pair of modestus (May 1) on Tsushima, they are already in full breeding condition, black bill, blue lores and flowing aigrettes, which is typical for the date. The tibia is a deep, reddish-pink and the tarsus black.|
|An albus (May 1) on Mishima. The large size is impossible to judge of course but the yellow legs and bill stand out at a time modestus are already black-billed.|