Demography and movements of the omao (Myadestes obscurus)

C.J. Ralph; S.G. Fancy

doi:10.2307/1369332

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Demography and movements of the omao (Myadestes obscurus)

C.J. Ralph·S.G. Fancy

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Abstract

Density, age-specific survival, timing of breeding and molting, and movements of the Omao or Hawaiian Thrush (Myadestes obscurus) were studied at four sites on the island of Hawaii. Mean monthly density (birds/ha) was 3.23 +- 0.57, 1.07 +- 0.33, 3.23 +- 0. 16, and 3.74 +- 0.36 at Kau Forest, Hamakua. Keauhou Ranch, and Kilauea Forest study areas, respectively. Annual survival of juvenile Omao (0.40 +- 0.09) was lower than that of adults (0.66 +- 0.08). Emigration and mortality was greatest during November through May. Breeding and molting occurred throughout the year, with peak breeding in May through July. Omao showed strong site fidelity and were highly sedentary. Mean home range size (n = 39) was 2.20 t 0.26 ha and did not differ between sexes or study sites.

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C.J. Ralph, S.G. Fancy. 1994. Demography and movements of the omao (Myadestes obscurus). https://doi.org/10.2307/1369332

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