A record of the northernmost location of Otus elegans in the Pacific area

Abstract

This individual of Otus elgans was rescued on Udo Island located in the east of Jeju Island, the southernmost part of the Korean Peninsula, on January 4, 2007. It was found at 3° 32″ N, 2° 58′ E, which is the northernmost record among the habitats of Otus elegans. After that, we took photographs of its shape, recorded its calls, and analyzed them. While analyzing we confirmed that it is an unrecorded species in Korea. We classified the chick calls based on structural similarity on spectrograms (view range: 0–7.5 kHz; window length: 1 second). We measured it and the results are; weight: 86.7 g, total length: 210 mm, wing length: 170 mm, tail length: 68.0 mm, and Tarsus length: 25.13 mm. In addition, its vocalizations are structurally diverse: duration, ∼10 ms to 1.5 s; peak frequency (adults), <900 to >3000 Hz. Currently, it was found not only on Nansei Shoto, Minami-daito-jima, and Okino Islands in Japan but also on the Batanes Islands in eastern China and the Babuyan Islands. Moreover, assumed that it inhabits Okinoshima, lying beyond the known northern limit of distribution. Therefore, this study record demonstrates the attempt of O. elegans to move north even to Udo Island from the previous habitats.