ANN ARBOR, Mich.—The University of Michigan Museum of Zoology recently received the carcasses of 15 rare Hawaiian birds called Newell's shearwaters. The specimens were processed at the museum, and tissue samples from the salvaged birds will be used to study foraging habits, genetic differentiation and former population size.
The birds died when they flew into power lines and buildings, an ongoing source of mortality for Newell's shearwaters, which are endemic to Hawaii and are listed as threatened by the U.S. Fish and Wildlife Service.
The specimens were processed by Janet Hinshaw, collection manager of the museum's bird division. Information about each specimen was entered into an online searchable database called ORNIS (www.ornisnet.org). ORNIS links information about the roughly 207,000 U-M Museum of Zoology bird specimens with data from 42 other bird collections and makes it available to scholars worldwide.
"The U-M bird collection dates from the 1830s and comprises approximately two-thirds of the planet's bird species," said Diarmaid Ó Foighil, professor of ecology and evolutionary biology and director and curator of the U-M Museum of Zoology.
"The collection's specimens, and the historical, genetic and ecological data they embody, are particularly important in a time of rapid global change," he said. "In addition, they are extensively used to address fundamental questions in biodiversity research."
Tissue samples from the Hawaiian birds will be used by a multi-disciplinary research team that is analyzing stable isotopes and DNA from Newell's shearwaters and another rare species, the Hawaiian petrel. These birds are two of the most abundant species of seabirds in the Hawaiian paleontological record, providing an ecological perspective that predates human settlement of the archipelago.
The Newell's shearwater measures 12 to 14 inches in length and has a wingspan of 30 to 35 inches. It was once abundant on all the main Hawaiian islands. Today, most of the birds nest along cliffs, 500 to 2,300 feet above sea level, on Kauai.
This seabird was reported to be in danger of extinction by the 1930s, according to the Fish and Wildlife Service. The introduction of the mongoose, cats, black rats and the Norway rat likely played a role in reducing the population of these ground-nesting seabirds.
Another threat to the birds is their attraction to electrical lights. Fledgling shearwaters attracted to manmade lights can become confused and fly into utility wires and poles, trees or buildings. Between 1978 and 2007, more than 30,000 dead Newell's shearwaters were picked up by island residents from Kauai's highways, athletic fields and hotel grounds, according to Fish and Wildlife.
Tissue samples from the shearwaters processed at U-M will be analyzed by a team that includes scientists from Michigan State University, the U.S. Geological Survey, the University of Buffalo and the Smithsonian Institution. Their study focuses on Newell's shearwaters and Hawaiian petrels.
"By studying tissues that are grown at different times of the year, we obtain information on diet during the breeding and non-breeding season," said Peggy Ostrom, a professor in Michigan State's Department of Zoology. "This is particularly useful because the non-breeding season is a time when very little is known about the diet of these far-ranging pelagic seabirds. During this time, the birds do not return to land. Instead, they forage thousands of mile out to sea."
The U-M Museum of Zoology contains more than 15 million specimens, with extensive collections in insects, mites, mollusks, fish, amphibians and reptiles, birds and mammals.
- U-M Museum of Zoology: www.ummz.umich.edu
- Newell's shearwaters: http://hawaiianendangeredseabirds.org/newells-shearwater or http://www.fws.gov/pacificislands/fauna/newellsshearwater.html