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PUBLISHED: 4:21 PM on Wednesday, October 31, 2007
Google Earth gives migration glimpse
When Google Earth launched in 2005, users delighted in typing in their home address, seeing the earth as if they were floating in space, and then plunging down to view a satellite image of their house, school or local glacier.

Now many of them have upgraded their free versions of Google Earth, which marries satellite and aerial images with mapping capabilities.

The upgrades allow all sorts of applications including helping to search for missing aviators and checking out Whale Sharks in the Indian Ocean.

One of the most interesting uses in Alaska employs the technology to track bird species. Earlier this year a group of international scientists started following the migration routes of Black Oystercatchers as they moved from Prince William Sound, Middleton Island and Portland Island off Juneau to British Columbia and other spots relatively balmy in winter.

Another study is tracking the fast migration of Bar-tailed Godwits from Alaska to New Zealand and Australia.

Black Oystercatchers are large, striking, and noisy birds. They're found along rocky shores in Alaska all the way down to Baja California. But their migration routes have been a mystery. That's finally changing.

With a glimpse, one might confuse the Black Oystercatcher with a raven, except for its bill and its legs and its call. The bill is long and bright orange. The bird's legs are also long, and pastel pink

Mike Goldstein is an ecologist with the United States Forest Service. He has studied Black Oystercatchers with researchers from federal and state agencies and Parks Canada for the last five years. The group started a new project this spring, the first of its kind tracking the bird's migration patterns.

"One big piece of the puzzle was how do birds use the environment once they leave their nest site. We know when they're coming back to nest, we know what they're doing when they're on their nest, but we don't know where the go afterwards," he said.

The scientists were especially interested in how large development projects and industrial accidents such as oil spills could affect bird behavior.

They also wanted to see if kayakers and other forms of recreation bothered them. Understanding the birds' movements is essential to conserving the birds' habitat.

Black Oystercatchers are not a threatened species. But they are listed as a species of high conservation concern. That's because of their small population. Scientists estimate fewer than 11,000 of these birds populate the earth. Black Oystercatchers are on Audubon Society's watchlist.

Portland Island, about 15 minutes by boat from Juneau's Auke Bay, is a hotspot for Black Oystercatchers in late summer, according to Goldstein.

The island has a long reef with a variety of blue mussels, limpets and other inter-tidal invertebrates that the birds find delicious.

They use the island for nesting and later as a place to rest and fatten up before heading south.

Working with a veterinarian from the Columbus Zoo in Ohio, the research group trapped six Black Oystercatchers on Portland Island. They surgically implanted a tiny radio in each bird's chest cavity. Radio antennas now stick out through the birds' tail feathers. One leg on each studied bird was also tagged.

The radio transmitters send signals to satellites that allow researchers to follow the birds. Goldstein says in addition to the Portland Island birds, a dozen others found on Middleton Island and in Prince William Sound are also being tracked. The study is due to finish when batteries in the transmitters die, sometime in early 2008.

From his office in Corvallis, Oregon, Matthew Johnson is in charge of organizing data from all the different field sites involved in the research. The wildlife ecologist with the U.S. Geological Survey said Google Earth technology has brought new advantages.

Johnson said scientists anywhere can quickly log on and track studied Black Oystercatchers. So can armchair ornithologists. "Anyway we can help the public understand our work and conservation efforts is a benefit," he pointed out.

For anyone interested in following the birds' routes over the fall and winter, can log onto http://fresc.usgs.gov/products/blackoystercatcher/ptt_results.html.

Johnson said he updates the site weekly or more often when they birds do something particularly interesting.


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