The Mariana Common Moorhen: Decline of an Island Endemic

Current status of Mariana Common Moorhens (Gallinula chloropus guami) in the Mariana Islands was determined by wetland surveys. A total of 300-400 moorhens exist on Guam, Saipan and Tinian. Extinctions have occurred recently on Pagan and prehistorically on Rota. A review of literature, field notes, and habitat loss indicates the subspecies' total population has probably been reduced by at least 36-52% in this century. The degradation and loss of wetlands and introduced competitors and predators pose the greatest threats to the moorhen in the Marianas.