Yosemite home to great grays

[ERIC]

Yosemite home to great grays

Written by Alex MacLean, The Union Democrat October 16, 2012 11:30 am
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Researchers using new methods to study a highly endangered species of owls in Yosemite National Park have been making some surprising finds.

According to officials in Yosemite, scientists over the past several years have used these methods to learn new information about a subspecies of the endangered great gray owl found only in the Sierra Nevada.

The new methods are considered noninvasive, meaning they allow scientists to study the animal without actually disturbing it in its natural habitat.

Yosemite spokeswoman Kari Cobb said these noninvasive measures are important considering the scarcity of great gray owls in California. The park is home to about 150 such owls, accounting for roughly 65 percent of the total population in the state.

“If the birds feel threatened or stressed they may not nest back at Yosemite,” Cobb said. “By utilizing the noninvasive research methods, it allows the animals to essentially live a wild existence without any sort of human disturbance and creates a safe environment for them to raise their young.”

Yosemite researchers in collaboration with the U.S. Forest Service and the University of California, Davis, have been installing passive recording devices along the edges of meadow habitats where owls are believed to nest.

The recording devices allow researchers to listen for clues that help them locate the raptors and their nesting sites without disturbing them by physically searching for them.

This summer, an owl nest was located thanks to the recording devices. The find was significant because the nest was in a lodgepole pine snag, which is the first recorded instance in California of a great gray owl nesting in such a snag.

Great gray owls typically nest in fir snags, according to the park.

One nest snag researchers found had fallen over in a summer windstorm and the juvenile owls that inhabited it were presumed dead, but it was confirmed through recordings that they had actually survived the fall and were still being fed by their mother.

Another new research method being deployed is the collection and analysis of molted feathers. The DNA found in the collected feathers allows scientists to study the owl’s survival rates, reproductive patterns and other important information, Cobb said.

“Providing habitat is essential to the great gray owls survival, and Yosemite does just that,” she said. “It’s something very special for us to be able to protect the birds and help them.”

According to Cobb, protecting the great gray owl is one of the park’s “highest research priorities.”