Saturday, August 27, 2011

A New Shearwater Species, Most Likely Extinct

Federal scientists have discovered and named a new bird species for the United States, Bryan's Shearwater.
For the first time in decades, researchers have found a new bird species in the United States. Based on a specimen collected in 1963 on Midway Atoll, Northwestern Hawaiian Islands, biologists have described a new species of seabird, Bryan’s shearwater (Puffinus bryani), according to differences in measurements and physical appearance compared to other species of shearwaters. Scientists at the Smithsonian Conservation Biology Institute analyzed the specimen’s DNA to confirm that it is an entirely new species....

The Bryan’s shearwater is the smallest shearwater known to exist. It is black and white with a black or blue-gray bill and blue legs. Biologists found the species in a burrow among a colony of petrels during the Pacific Ocean Biological Survey Program in 1963. Peter Pyle, an ornithologist at the Institute for Bird Populations, recently examined the specimen and found that it was too small to be a little shearwater (P. assimilis) and that it had a distinct appearance.

According to Fleischer and Andreanna Welch, a former graduate student and Smithsonian predoctoral fellow at SCBI who worked on the genetic analysis, the Bryan’s shearwater differs genetically to a greater degree than found between most other species of its genus, and is distantly related to another similar looking species, the Boyd’s shearwater (P. boydi). Based on this DNA evidence, researchers estimate that the Bryan’s shearwater separated from other species of shearwaters perhaps more than 2 million years ago. These findings have been published in a paper, "A New Species of Shearwater (Puffinus) Recorded from Midway Atoll, Northwestern Hawaiian Islands," in the current issue of The Condor.

Researchers do not know where Bryan’s shearwaters breed. According to Pyle, shearwaters and other seabirds often visit nesting burrows on remote islands only at night, and researchers have not discovered the breeding locations of many populations. Individual seabirds from colonies also often “prospect” for new breeding locations, usually far from existing colonies. Bryan’s shearwater could conceivably breed anywhere in the Pacific ocean basin or even farther afield.

“We don’t believe that Bryan’s shearwaters breed regularly on Midway or other Northwestern Hawaiian Islands, based on the extensive seabird work in these islands during the Pacific Seabird Project,” Pyle said. The specimen was the only observation during this extensive project, which occurred on islands and atolls throughout the North Pacific from 1963 until 1968. “They would have encountered more Bryan’s shearwaters if they bred regularly in the Northwestern Hawaiian Islands.”

Given that Bryan’s shearwaters have remained undiscovered until now, they could be very rare and possibly even extinct.
The abstract of the paper is available here.

It is sad to think that a newly discovered species might already be extinct, but that is not surprising for birds that have gone undiscovered for so long, especially ones that occur within the United States and its territories.