E7, a female bar-tailed godwit, has touched down in New Zealand following an epic, 18,000-mile-long (29,000-kilometer) series of flights. Scientists with the U.S. Geological Survey tracked the flights of the large, streamlined shorebird by satellite. During her journey, E7 set the record for the longest nonstop flight recorded for a land bird.

USGS' Alaska Science Center tracked the odyssey of the godwit as part of an ongoing collaboration with colleagues in California and New Zealand. By studying the routes of wild migratory birds, like E7, scientists hope learn more about birds' potential to transmit the highly pathogenic avian influenza H5N1. “The transmitters show us the precise migratory routes — where they stop and how long they stay,” Bob Gill, a USGS researcher, said.

Scientists named “E7” after the tag on her upper leg. She is one of 16 godwits scientists captured and tagged in New Zealand in early February 2007. New Zealand scientists fitted each bird with a small, battery-powered satellite transmitter. USGS scientists hoped the transmitters’ batteries would last long enough to track the birds’ northward migration to Alaska.

On March 17, E7 departed Miranda on the North Island of New Zealand and flew nonstop to Yalu Jiang, China. She completed the 6,300-mile-long flight in about eight days. There E7 settled in for a 5-week-long layover before departing for breeding grounds to nest.

On the evening of May 1, she headed east out over the Sea of Japan and the North Pacific. Eventually turning east, E7 headed northeast toward Alaska, crossing the end of the Alaska Peninsula. She was on her way to her eventual nesting area on the Yukon-Kuskokwim River Delta in western Alaska. E7 also completed this flight without stopping, covering some 4,500 miles in five days.

Researchers then tracked E7 to the coast of the Yukon Delta where she joined other godwits preparing for their return flight to New Zealand.

Early on the morning of August 29, E7 took off southeast back across the Alaska Peninsula. Flying over the vast North Pacific, she headed toward the Hawaiian Islands. Less than a day's flight from the islands, E7 turned southwest. She then crossed the Hawaiian Archipelago over open ocean 125 miles west of Kaua and headed toward Fiji. E7 crossed the dateline about 300 miles north-northeast of Fiji and then appeared to fly directly over or slightly west of Fiji. She continued south toward New Zealand, her journey continuing to amaze researchers.

“It’s an eye-opening experience," Gill said. "Using transmitters and satellites, we can zoom in within a few hundred meters of the bird’s location."

In the early afternoon of Sept. 7, E7 passed just offshore of North Cape, New Zealand, and then turned back southeast. She made landfall in the late evening at the mouth of a small river, 8 miles east of where she had been captured seven months earlier.

The last leg of E7’s journey is the most extraordinary. Entailing a nonstop flight of more than eight days and a distance of 7,200 miles, it equals flying roundtrip from New York to San Francisco, without ever touching down.

Since they are land birds, godwits like E7 can't stop to eat or drink while flying over open ocean. Her constant flight speeds, which scientists also tracked by satellite, indicate that she did not stop on land.

Godwits do not become adults until their 3rd or 4th year, and many live beyond 20 years of age. If 18,000 miles is the average distance the birds fly each year, then an adult godwit would fly some 288,000 miles in a lifetime.

USGS and the Point Reyes led the study that recorded E7’s epic flight. The collaborative effort included cooperators from Massey University and Miranda Shorebird Centre, New Zealand, and The Global Flyway Network. The David and Lucile Packard Foundation, the USGS, Alaska Science Center, and the U.S. Fish and Wildlife Service provided funding for the project.

For more information, or to track E7, the bar-tailed godwit, go to http://alaska.usgs.gov/science/biology/shorebirds/index.html