The imperial amazon (Amazona imperialis) or Dominican amazon, also known as the sisserou or sisserou parrot, is a parrot found only on the Caribbean island of Dominica. It has been designated as the national bird of Dominica. The species is critically endangered. In 2019, it was estimated there were only about 50 mature individuals left in the wild. Description The imperial amazon measures an average of in length. With males weighing an average of and females , the species is large for its genus. Being of the family Psittacidae, the sisserou has zygodactyl feet and a thick, hooked bill with a muscular tongue. This bill is fashioned in such a way that, using its hinged mandibles and tongue, the sisserou can easily move food around in its mouth. Males and females have identical plumage: the chest is a dark shade of purple, and the upper parts and feathers are a dark shade of green, with black-edged feather tips. The eye-ring is dark brown, with the eye being a mix of orange and red. Juvenile appearance does not differ much, with a higher occurrence of green plumage and strictly brown eyes. Behavior The call of the sisserou resides in the higher frequencies, a loud and even "squeaky" mix between shriek, squawk, and trill. They are shy, difficult to approach, and usually travel in groups of three or fewer. They sometimes flock together with red-necked amazons. They are good climbers and strong flyers with powerful wings. They prefer to perch on the tops of trees. They are difficult to detect, as they are well camouflaged by their plumage. Breeding Between February and April, nesting occurs and the female will lay a clutch of two white eggs in a deep cavity inside a rainforest tree, returning to the same tree year after year. For 26–28 days, the female will incubate the eggs. During fledging, which occurs between June and early September, both parents will take care of and feed the chicks until they are fully feathered and ready to leave the nest. The chicks use typical "begging calls" when hungry, to which either parent will respond with food. Usually only one chick survives to fledging and, typically, sisserou pairs fledge a single chick every other year; however, there have been documented exceptions. These parrots mate for life and are extremely faithful to each other. They might seek another mate only after a mate