Please identify this bird. It's an egret, but what species?
Intermediate Egret Egretta intermedia
Resin, how can you tell the difference between this bird and a Great Egret?
With difficulty! But fortunately, the pic shows the head well; on Intermediate, the bare area around the gape doesn't go behind the eye, on Great it does. And it doesn't on this pic. Here's a couple of Great Egret pics showing the gape going behind the eye:
and with the gape open (!): http://orientalbirdimages.org/search.php?p=6&Bird_ID=1110&Bird_Family_ID=&pagesize=1