Seasonal Change of Vocalization of the Okinawa Rail (Gallirallus okinawae)

Abstract

We studied the relationship between activities and seasonal changes of vocalization of the Okinawa Rail (Gallirallus okinawae) in northern Okinawa Island. The vocalization of this species is recognizable as three patterns: ‘kek’, ‘krr’ and a duet song of a pair. The ‘kek’ song was most frequently recorded from April to June. Moreover, the time period when the ‘kek’ song was heard changed with seasons. In March to June, August to October, and November to February, the ‘kek’ song was heard most frequenctly from 6:00 to 9:00 and 15:00 to 18:00, 18:00 to 21:00, and from 12:00 to 15:00, respectively. Because the ‘kek’ song was recorded in April to June, the breeding season, a relationship between the ‘kek’ song and breeding behavior was suggested.