コサギ
2 sightings
It looks quite similar to the Great egret - one way to tell it apart is that it is smaller, although it can be hard if you don’t really have a frame of reference. The other way is that the beak is black, and although it has black legs it has these funny yellow feet.
It also has a plume on head during the breeding season.
Took this one in winter, so no plume here. You can just about make out its yellow feet in the grass.
Spotted this guy fishing by the water on Odaiba's beach. You can see the plume on its head.