When a cattle egret (Bubulcus ibis) flew up to sat on a tree at dawn, I had to take out my camera to take some photos. After having spent some time in my initial years of watching birds, I’ve given up looking at these white egrets. They are very common, and since the four species are not terribly easy to tell apart, I don’t usually bother to either record them or to look hard. Cattle egrets are the easiest to tell apart from the others; they always have some yellow on them. In the breeding season it covers their head, neck, and back. In winter, the yellow recedes to a small patch on its forehead, as you see in the photo above.
To identify the other white egrets you have to look at the feet and beaks. Since the birds are usually seen in extremely muddy places, this is not easy. The little egret (Egretta garzetta) has a dark beak, dark legs, and yellow feet. In breeding season it has two long plumes hanging behind its nape. The large egret (Casmerodius alba, formerly Ardea alba) has dark legs and feet. Its beak is dark in the breeding season, and yellow otherwise. In both seasons it has a dark line extending from the beak under its eyes and beyond. This is called the gape line. If you see it flex its somewhat longer neck, you might see a kink in the neck. In the photo above (taken last February near Jamnagar), the gape line clearly extends beyond the eye, and there is a definite S-shaped kink in the neck, both telling us that this is a large egret. The intermediate egret (Mesophoyx intermedia, formerly Ardea intermedia) is the most confusing. Its legs, feet, and beak are very similar to that of the large egret, but the gape line stops below the eye. Also, its neck is a little shorter, and does not kink into an S-shape. Distinguishing them is always a puzzle, and I’m never sure that it worth taking the time to solve.