Amelia strongly resembles the Crested Caracara, a bird of prey native to South America.

She is an eagle with a red face, a white beak, cyan eyelids, black, navy blue, white feathers, and she initially wears a spider web shirt. Tiffany also has the spider web shirt as her initial clothes. In Animal Forest, Amelia looks the same as she is in in later games, only that she has no eye liner.

Her name may be a reference to Amelia Earheart, the first female pilot to take flight.

http://animalcrossing.wikia.com/wiki/Amelia