May 12, 2007
Bar-tailed Godwits arrive back in Alaska
At least four of the Bar-tailed Godwits being tracked by satellite have reached their breeding grounds in Alaska after stopping in the Yellow Sea to put on extra fat for the final journey and establishment. As you can see from the Google Earth image (below) employing satellite tracking data, these birds have completed some mammoth flights from New Zealand to the northern end of the Yellow Sea non-stop. The incredible thing is that these Olympians of the air flew over extensive areas of intertidal mudflats in the southern part of the Yellow Sea but chose to continue on to their chosen locations in various parts of China and Korea.
The migration of the satellite-tagged godwits displayed on Google Earth. © 2007 Google Earth. Press image for enlargement.
If you have Google Earth on your computer, visit the USGS site. The site has instructions for downloading a link to Google Earth which displays the journey locations as overlays.
A summary of the birds’ movements up until 8 May 2007, as reported by Phil Battley: During the third week of March, 10 of 14 satellite-tagged Bar-tailed Godwits departed from New Zealand on their northbound migration.
During the first week in April, 3 more birds departed from New Zealand. Six of the birds arrived at coastal staging sites in South Korea, China, and Japan after completing a very long (>10,000 km) transoceanic flight in just over 7 days.
One bird (32919) migrated north in a few shorter flights. This bird stopped at Yap, Micronesia for a month, then traveled to Okinawa, Japan for a week, and now is on the coast west of Yalu Jiang, China. Members of the Okinawa Wild Bird Society were able to locate and photograph the bird during its stay on Okinawa.
Only 1 bird (40158) is still in New Zealand and it is at Golden Bay on the South Island. This bird continues to use the same roosting sites on Farewell Spit and feeding areas on the central mudflats of Golden Bay.
Starting on 1 May, four birds departed from coastal staging sites in Asia (40157 from Asan Bay, South Korea and 40015, 40156 and 40155 from Yalu Jiang, China) and embarked on >5,000 km migration flight to breeding grounds in Alaska.
40156 first made landfall in Alaska at Cinder River lagoon on the north side of the Alaska Peninsula. The next day this bird flew to the north shore of Kvichak Bay and is now just inland of the bay.
40015 landed in the interior Yukon Delta near a lake north of Baird Inlet.
40157 is just south of Baird Inlet on the Yukon Delta.
40155 is currently stopping over at Mud Bay on the south side of Port Moller on the Alaska Peninsula.
40160 remains at Asan Bay where it was observed and photographed (along with 40157) on 16 April during a survey by the Saemanguem Shorebird Monitoring Programme. Check out their website.
40159 remains at Suncheon Bay, South Korea where it went after first stopping over at Tshushima Island, Japan.
The transmitter on 36119 stopped working at Baong Island, Papua New Guinea on 10 April, but fortunately this bird was recently seen and photographed by in Queensland, Australia. It is astonishing that 4 of these 14 birds have been observed by people at locations 100s to 1000s of km from their banding sites! We are very grateful to everyone who has sent us information about these birds.
The transmitter on 36118 stopped working when the bird was in the southern Philippines, and we do not currently know the fate of this individual.
Another bird (32920) stopped for a few days on the southern coast of Papua New Guinea before turning back to Queensland, Australia.
An additional three birds (39590, 36117, 40161) were on their way to the Yellow Sea area when their transmitters stopped functioning. We will have to wait for visual observations of these birds to determine their fate.
- Data courtesy of Lee Tibbitts
Researchers are also migrating from across the Asia Pacific to be with shorebirds in Alaska, either to recover the birds with satellite transmitters or to take samples to test for avian influenza. Stay tuned for more exciting news over the breeding season and when the birds make their epic journey back across the Pacific Ocean.