There are many different animals in Kawai Nui Marsh. The endangered birds are called the Hawaiian stilt or ae'o, coot or alae ke'oke'o, and the moorhen or the alae'ula. There are other birds called the Black Crowned heron and the frigate birds. The wing span of this bird is about 6 feet long. There are also many fish in Kawai Nui Marsh. Some of the fish are goby or in Hawaiian o'opu. There are other fish like the milkfish and mullet. There are also many shrimps in Kawai Nui Marsh that are a source of food for many of the animals.