I'd check that "I" is definitely the fourth letter, because "egret" could be the answer.
The ibis is a wading bird.
avocet
Rail.
avocet
ibis
heron
avocet
Bittern, Limpkin.
American Bittern
A wading bird is any of a group of long-legged birds, such as cranes, herons or storks, which wade in shallow water in search of food.
grebe
Avocet
Avocet