The Clutch Size of the Black-winged Stilt Himantopus himantopus himantopus

Abstract

The number of eggs in nests of the Black-winged Stilt Himantopus himantopus himantopus in areas in Tokyo Metropolis and Chiba Prefecture, around the Tokyo Bay was investigated. The mean ± SE number of eggs in nests was 3.50±0.06 (n=384, range 1-10). Instances of five or more eggs in a nest were suggested to have been produced by two or three females. The mean ± SE of clutch size by monogamous pairs was 3.36±0.05 (n=362, range 1-4).