A Shearwater's Survival

We don’t often see an exclamation point in an ornithological paper’s title, but the one in a scientific report this week is excitingly appropriate: “Bryan’s Shearwaters have survived in the Bonin Islands, Northwestern Pacific!”

Bryan’s Shearwater was formally described as a new species just last year, based on an old museum specimen from Midway Atoll. The species was thought possibly to be extinct, but it is now documented as recently as 2011 on a Japanese island in the Bonin archipelago about 600 miles south of Tokyo. (The archipelago is named Ogasawara Islands in Japan.) Perhaps these islands contain the shearwater’s undiscovered breeding grounds as well, according to Japanese researchers.

Kazuo Horikoshi and five colleagues from Japan announced discoveries of recent Bryan’s Shearwater records on February 8 at a meeting of the Pacific Seabird Group in Hawaii.

The key to the new discoveries was the old specimen analyzed by Peter Pyle, Andreanna Welch, and Robert Fleischer in 2011. (See News and Notes in Birding, January 2012, p. 22.) They judged the bird's morphological and genetic characters to be distinct from all other species, and they named it Puffinus bryani.

Turn now to the northwestern Pacific. Six small shearwaters found in the Bonin archipelago from 1997 to 2011 could not be assigned to any known species. But when the Bonin birds were compared with the Pyle team’s bird, they matched the morphological and genetic characters of Bryan’s Shearwater.

The excitement is tempered by a serious conservation concern. Three of the six birds found on the Bonin islands were carcasses preyed upon by rats. Horikoshi and his coauthors call for searches to locate the species’ breeding grounds. If these are on rat-infested islands, eradicating the rats will be essential to this shearwater’s survival.

In a separate presentation at the meeting, Pyle and four coauthors updated the group on information about breeding habitats, vocalizations, and potential at-sea records of Bryan’s Shearwater in the North Pacific. They also suggested conservation steps to protect this obviously rare and threatened species.

Read abstracts of the history-making announcements on the Pacific Seabird Group website. The Horikoshi team’s report is on page 37 and the Pyle group’s report is on page 78 of the 115-page file.

Despite some errors in the reporting, it is encouraging to see prominent coverage given to the discoveries in Japanese media, such as articles in the Mainichi Daily News and the Asahi Shimbun. Financial and conservation support from Japan—and broad international support, too—will be necessary to save what is obviously a rare and most likely endangered species.