Surprise findings from Bar-tailed Godwit satellite tracking
Eight satellite-tagged Bar-tailed Godwits are making their way back to NW Australia after an arduous journey to Siberia and back, via a ‘refueling stop’ in the Yellow Sea. The first bird, flag number C3, making landfall today.
Terrible weather conditions in Siberia
It appears that they had an awful breeding season due to severe weather conditions which interrupted the life cycle of the insects which are crucial to the survival of young birds. Out of the fifteen godwits fitted with satellite transmitters two died on the breeding grounds and contact was lost with two other birds, probably due to equipment transmission failure. The other three birds did not leave Australian waters. It is hard to determine the age of shorebirds after their second year and it is possible that these three birds were not ready to migrate to their breeding grounds..
Confirmation of nearly 30 years of research
The amazing effort by the international research team have confirmed results of work carried out by the Australasian Wader Studies Group and co-workers in other countries in the East Asian Australian Flyway, now getting close on 30 years, that Australian Bar-tailed Godwits breed in eastern Siberia while New Zealand birds breed in Alaska. However the return movements via the New Siberian Islands to the north of the breeding grounds came as a big surprise.
A map depicting the flight routes of the Bar-tailed Godwits from Australia and New Zealand. © 2008 USGS. Press image for enlargement.
This year Bar-tailed Godwits that over-winter in New Zealand and Australia took almost identical migration routes on their way northwards to their stopover sites in the Yellow Sea. From there the birds flew in different directions, the New Zealand birds flew to the east, to Alaska, while the Australian birds flew in a more direct, northerly direction to Eastern Siberia. Both the Australian and New Zealand birds spent about five weeks in the Yellow Sea beforehand to recover and put on enough fat before flying to their nesting places. Most of the ‘Australian’ birds appear to have used exactly the same places to stop on their southward migration as they did migrating north.
Few researchers have ever been to the New Siberian Islands but it would appear, from reports from Professor Pavel Tomkovich in Russia, that food becomes available in the New Siberian Islands too late for nesting birds but in time for birds to put on fat before migrating south to the Yellow Sea.
Staging areas
Key staging areas in the Yellow Sea include Yalu Jiang Wetlands Nature Park (near the border with North Korea), Bo Hai Bay and the Rudong Coast, about 90km north of Shanghai. Yalu Jiang has been subject to extensive studies by Chinese and New Zealand researchers (from a sister site at Miranda, New Zealand). Bo Hai Bay is currently subject to major studies by researchers from Beijing Normal University and Fudan University in Shanghai. Rudong coast has received regular surveys by local ornithologists Lei Ming and Zhang Lin, who have identified the area as a major feeding site for large numbers of migratory birds as well as other waterbirds. According to colour flag sightings, Saemangeum and nearby wetlands are (were!) also major staging areas for these migrating Bar-tailed Godwits.
You can find out more about this project at the Alaskan Science Centre pages on the USGS site. By clicking on the Update page you will see the daily progress of godwits from both New Zealand and Western Australia. There is a black godwit icon at the bottom of the page which, when clicked on will download an icon to your desktop which will activate Google Earth with the journey of the birds mapped on it. By clicking on the Maps page you can select individual godwits to follow. Have fun!