First breeding records of the osprey (Pandion haliaetus) on Jeju Island, South Korea

Abstract

The first breeding of osprey ( Pandion haliaetus ) on Jeju Island, South Korea, were observed in 2015, and ospreys bred on three sites. We found a total of three nests and observed that A site nest bred on successfully from 2017 to 2020. The number of eggs per clutch ranged from two to four, with a mean ± SD of 3.16 ± 0.75. The nesting period varied from 71 days to 79 days, with an average duration of 76.2 ± 3.18 days. The incubation period ranged from 34 days to 38 days, averaging 35.8 ± 1.72 days. Fledging dates ranged from July 4th to 13th. The nest tree species was Pinus thunbergii , and the average tree height was 16.2 ± 3.12 m. On average, the nest height from the ground was 14.8 ± 2.57 m. The average diameter at breast height of the nesting trees was 36.1 ± 2.02 cm. Of the total 19 eggs produced, the hatching rate was 91.4% ± 10.2%, fledgling rate was 68.6% ± 26.9%, and breeding success was 65.6% ± 25.1%. Little ecological information is available on osprey living in South Korea; therefore, this study makes a meaningful contribution to provide baseline ecological data from South Korea for this species.