This species, found only in a portion of northern Okinawa, became known to science only as recently as 1981. Its discovery that year was a great surprise to ornithologists. No new bird had been discovered in Japan since 1922 (and that was a nocturnal storm-petrel). Local people, however, in the forested Yambaru region of Okinawa had in fact known of the bird, calling it “Agachi” or “Yamdoi”.
The Okinawa Rail has commonly been believed to be flightless, but that may not be entirely so. Some birds sleep at night in trees, as high as 11 meters above the ground. Others (some adults and all chicks) have been found to sleep on the ground. While it’s normally very difficult to see this usually shy bird in the forest, it can be easy to hear one. The call carries far. Peak singing is around sunset and sunrise. Pairs duet.
The population of the Okinawa Rail is estimated at about 1800 birds, or 900 pairs