Ancient Murrelet

Ancient Murrelet Synthliboramphus antiquus

Common with breeding in Teuri-to (Hokkaido). 

There are records that breed in Moyururi-to, Habomaimoshiri-to (both Hokkaido) and Sangan-jima (Iwate) in the past. In addition to this, there is a possibility they breed in Tobi-shima (Yamagata) and Awa-shima (Niigata). It is difficult to survey because their typically nest is short burrow made in cliff, the current situation is unknown in many breeding sites.
In the winter, a large number of birds come to around Japan. And a few of them are observed at sea off Kyusyu Region and Okinawa.

Fig. 1. Adult non-breeding.
Fig. 2. Imm.?
Fig. 3. Adult non-breeding.
Fig. 4. Adult breeding & non-breeding birds.
Fig. 5. Adult breeding birds.
Fig. 6.
Fig. 7. Imm.?
Fig. 8. The left one has breeding plumage and a black throat like a bib cf. Japanese Murrelet.
Fig. 9.