Bonin petrel

Its secretive habits, remote breeding colonies and limited range have resulted in few studies and many aspects of the species' biology are poorly known.

The Bonin petrel was formally described in 1888 by the English naturalist Osbert Salvin and given the binomial name Oestrelata hypoleuca.

Its pale grey upperparts have darker primaries and wing coverts creating an "M" mark across the back.

Bonin petrel eyes contain high levels of the pigment rhodopsin which aids nocturnal vision.

Both parents participate in digging burrows, which are usually dug in sand or hard coral substrate, and are between 1 and 3 m long.

A single egg is laid by a pair each breeding season, if it is lost then no attempt is made to re-lay.

After the breeding season both chicks and adults migrate northwards to the seas off Honshū and Sanriku in Japan.

Prior to the arrival of humans the Bonin petrel nested on the main Hawaiian Islands, fossil remains have been found on Kauai, Oahu and Molokai.

These bones have been found in association with human archaeology, strongly implying that they were a food source for Polynesian settlers, along with other seabirds.

Habitat destruction limits breeding success on some islands, especially as it increases competition with more aggressive species like the wedge-tailed shearwater.

Conservation measures are in place to protect the Bonin petrel and other seabirds that share the species' breeding islands.

A Bonin petrel trapped in the sand on Midway Atoll by the 2011 Tōhoku earthquake and tsunami , before being rescued.
Bonin petrel chick