 |
We are studying the migration patterns of two subspecies of the Bar-tailed Godwit (Limosa lapponica). The baueri subspecies (blue range on map) breeds in Alaska, spends the non-breeding season in New Zealand and east Australia, and stops during northbound migration at staging areas in east Asia. The menzbieri subspecies (green range) breeds in Siberia, spends the non-breeding season in west Australia, and stages during northbound migration in east Asia. The ranges of both subspecies overlap in the Yellow Sea. |
 |
Bar-tailed Godwits need plenty of invertebrate foods to “fuel” their exceptionally long flights. |
 |
In February, we captured 9 godwits in New Zealand and 15 godwits in Australia and marked them with satellite transmitters to determine the routes and timing of their northbound migration. |
 |
Overview of Firth of Thames near the capture site of godwits on the North Island, New Zealand. |
 |
Birders look for shorebirds at Miranda near the capture site of godwits on the North Island, New Zealand. |
 |
Overview of Roebuck Bay near the capture site of godwits in Western Australia. |
 |
Godwits congregate in large flocks during the non-breeding season. This image is of a flock of thousands at Roebuck Bay. |
 |
Releasing a satellite-tagged godwit; birds recover quickly from tagging and fly away when released. |
 |
All birds were also marked with uniquely coded leg bands that allow us to identify individuals using binoculars or spotting scopes. This bird is marked “E1” and is a female with an implanted transmitter; note the antenna that is faintly visible along her tail. |
 |
We are tracking the godwits using satellite telemetry. This year birds from New Zealand began migrating on 14 March and, as of today (28 March), three have arrived in coastal China and North Korea, one has landed near Okinawa, and one is in the air north of Papua New Guinea. All birds flew non-stop along relatively straight routes at track speeds between 50 and 70 km/hr. There are three migration tracks depicted in this image (from the 2007 migration); the bird depicted in white traveled almost 4,000 km in just three days! |
 |
Many groups and individuals throughout the East-Asia Australasian Flyway are very interested in godwit ecology and conservation. Groups that are involved in this current study include Point Reyes Conservation Science, USGS Alaska Science Center, University of Massey, Miranda Shorebird Centre, New Zealand Ornithological Society, Global Flyway Network, and the Broome Bird Observatory. |
 |
Based on previous work, we know that the New Zealand godwits will stay in estuaries and bays in the Yellow Sea region until early May. They then will move on to breeding areas somewhere in Alaska. We are waiting to find out what route the Australia birds will take to get to Asia and where in Siberia these birds will breed. So keep checking this website to find out the answer to these questions!! |
