Bulwer’s Petrel

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Japanese name: アナドリ Anadori

Bulweria bulwerii

Status : Fairly common

Distribution : Breeds in Izu Islands (Tori-shima, Hachijo-ko-jima, Onohara-jima), Ogasawara Islands (Kitano-shima, Muko-jima, Higashi-jima, Minami-jima, Nishino-shima), Volcano Islands (Minami-iwo-to), Biro-to, Hamiya-to and Nakanougan-jima. Breeding population size in Izu Islands is poorly known. Nine nests on Muko-jima (in 2016), 33 nests on Nakodo-jima (in 2017) (鈴木ほか 2019), a minimum of 1,000 pairs on Higashi-jima and presumed 1,000 pairs on Minami-jima, three nests on Nishino-shima (in July 2004) (川上ほか 2018), presumed several thousands pairs on Minami-iwo-to (川上ほか 2019). There is the record of breeding on Kita-iwo-to before WWⅡ but there were no breeding birds on Kita-iwo-to when the survey conduced in 2019 (川上ほか 2019). There is the record of breeding on Biro-to in 1998 but after that the breeding status is unknown (中村ほか 1999). Adults fly and call on Hamiya-to but any nests are not found (環境省 2022). 261 adults are found on Nakanougan-jima in 2021 (環境省 2022). Adults calling and having brood patch are found on Onbase-jima and Danjo Islands (O-shima), so presumed breeds on these islands (環境省 2018).

Their breeding season is from June to Oct. Incubation in June on Minami-iwo-to (川上ほか 2018). Nest site selection varies by breeding sites (川上ほか 2018). On the Ogasawara Islands, for example, on Higashi-jima, they make burrows in the soil; on the Minami-jima, nest in vertical holes in rocks; and on the Nishino-shima, use crevices in rocks as nests(川上ほか 2005).

Fairly common in the area off the Pacific coast of between Chiba Pref. and Okinawa Pref., off the East China Sea coast of Tokara Islands (Apr-Oct). At times they are seen off the Pacific coast of Iwate Pref. when the sea temperature is high. It is not usually distributed on the Sea of Japan side, but has been recorded in Shimane Pref. (1982), Yamaguchi Pref. (1990), and Ishikawa Pref. (2000). These records are mainly after typhoons have passed. We observed and photographed one off Maizuru City, Kyoto Pref., in July 2020, but no effects of typhoons were observed before or after the observation date.

Ogasawara Islands and Iwo Islands

Fig. 1. Off Chichijima, Bonin Islands, Tokyo. Sep. 23 2020.
Fig. 2. Off Chichijima, Bonin Islands, Tokyo. Sep. 23 2020.
Fig. 3. Off Chichijima, Bonin Islands, Tokyo. Sep. 22 2020.
Fig. 4. Off Chichijima, Bonin Islands, Tokyo. Sep. 23 2020.
Fig. 5. Off Mukojima, Bonin Islands, Tokyo. Sep. 21 2020.
Fig. 6. Off Mukojima, Bonin Islands, Tokyo. Sep. 21 2020.
Fig. 7. Off Chichijima, Bonin Islands, Tokyo. Sep. 20 2020.
Fig. 8. Off Chichijima, Bonin Islands, Tokyo. Sep. 20 2020.
Fig. 9. Off Minami-iwo-jima. Jul. 5 2013.
Fig. 10. Off Minami-iwo-jima. Sep. 12 2009.
Fig. 11.
Fig. 12.

Okinawa Pref.

Fig. 1. Bulwer’s Petrel in front of Nakanouganjima. 2 Jul. 2022.
Fig. 2. Off Nakanouganjima, Okinawa. 2 Jul. 2022.
Fig. 3. Off Nakanouganjima, Okinawa. 2 Jul. 2022.
Fig. 4. Off Nakanouganjima, Okinawa. 2 Jul. 2022.
Fig. 5. Off Hatomajima, Okinawa. 3 Jul. 2022.
Fig. 6. Off Hatomajima, Okinawa. 3 Jul. 2022.
Fig. 7. Off Hatomajima, Okinawa. 3 Jul. 2022.
Fig. 8. Off Nakanouganjima, Okinawa. 2 Jul. 2022.
Fig. 9. Off Hatomajima, Okinawa. 3 Jul. 2022.
Fig. 10. Off Hatomajima, Okinawa. 3 Jul. 2022.
Fig. 11. Off Hatomajima, Okinawa. 3 Jul. 2022.
Fig. 12. Off Hatomajima, Okinawa. 3 Jul. 2022.
Fig. 13. Off Nakanouganjima, Okinawa. 2 Jul. 2022.

川上和人・山本裕・堀越和夫(2005). 小笠原諸島西之島の鳥類相. Strix, 23: 159-166.
川上和人・鈴木創・堀越和夫・川口大朗(2018). 2017年における南硫黄島の鳥類相.
Ogasawara reserch, 44: 217-250.
川上和人・鈴木創・堀越和宙 (2020). 2019年における北硫黄島の鳥類相. Ogasawara
reserch, 44: 217-250.
環境省(2018). 平成29年度モニタリングサイト1000海鳥調査報告書. 環境省自然環境局生物
多様性センター.
環境省(2021). 2020年度モニタリングサイト1000小島嶼（海鳥）調査報告書. 環境省自然環
境局生物多様性センター.
環境省(2022). 2021年度モニタリングサイト1000小島嶼（海鳥）調査報告書. 環境省自然環

境局生物多様性センター.
https://www.biodic.go.jp/moni1000/findings/reports/pdf/h29_seabirds.pdf
中村豊・児玉純一・井上伸之・岩﨑郁雄・岩切久(1999). 宮崎県におけるアナドリ
Bulweria bulwerii の繁殖初確認. 日本鳥学会誌, 47 (4): 145-147.
沖縄県(2017). 改訂・沖縄県の絶滅のおそれのある野生生物第3版(動物編)-レッドデータお
きなわ-. 沖縄県環境部自然保護課. 那覇.
鈴木 創・堀越和夫・佐々木哲朗・川上和人(2019). 小笠原諸島聟島列島におけるノヤギ排
除後の海鳥営巣数の急激な増加. 日本鳥学会誌, 68(2): 273-287.