Imagine crossing 3,500 miles of open ocean without stopping! Last week we heard about shorebirds arriving on the Atlantic Coast from South America. Today's news is about shorebird migration over the Pacific Ocean and along the Pacific Coast.
This report was prepared by Heather Johnson, Program Coordinator of the U.S. Fish and Wildlife Service's "Shorebird Sister Schools Program". The Shorebird Sister Schools Program allows students, teachers and parents to track Arctic nesting shorebirds to their nesting grounds in Alaska and Canada.
To: Journey North
From: Heather Johnson,
Shorebird Sister Schools Program Coordinator
Date: Tuesday, May 14, 1996
A Pacific Golden Plover that bird was banded in Oahu, Hawaii was detected in Alaska on April 23. The bird was in the Bering River Delta, near Cordova, Alaska. According to radio-telemetry data, it was last detected in Hawaii on April 19. This means it took 4 days or less for it to fly all the way to the coast of Alaska. WOW!! What incredible birds!
Research biologists Nils Warnock and Mary Ann Bishop are comparing the way two different species of shorebirds migrate. They put radio-tags on 20 Pacific Golden in Oahu, Hawaii and 70 Western Sandpipers in San Francisco, California.
The Pacific Golden Plovers fly to Alaska from Hawaii in one big trip without stopping. In contrast, Western Sandpipers come up the Pacific coast, stopping to feed along the way. The biologists want to find out why the Pacific Golden Plovers can go over 3,500 miles without stopping and the Western Sandpipers have to stop and refuel. What do you think?
This research will help to compare average migration time and length-of-stay at stopover sites of "short-hop migrants" (Western Sandpiper) and "non-stop migrants" (Pacific Golden Plover).
The radio tag is a very small transmitter, weighing .8 - 1.1 grams. It is glued to clipped feathers on the lower back of the bird with marine epoxy. The life of the radio transmitter is only about 30 days. When the birds feathers molt during the summer, the transmitter falls off and new feathers grow back.
These radio-tagged birds are being monitored by radio-telemetry from airplanes and from the ground. Each bird has a unique frequency which the biologists can pick up on a special receiver. Ideally they would be able to hear every bird each survey, but this does not always happen. Sometimes the tagged birds fly at different rates than others or are in an unexpected location. Also a bird may lose its radio-tag, be in a location where it was difficult to pick up the signal (such as behind a mountain, in a gully, etc.) or the signal can be too weak for the biologist to pick it up on thereceiver.
Shorebirds have been cruising up the Pacific Coast for almost a month now, stopping at major stopover locations to "refuel". They stop at the same special sites year after year, which are wetland sites with spectacular food supplies for hundreds of thousands of shorebirds to feed. Arctic nesting shorebirds travel in huge flocks, stopping together to feed and rest.
These birds have already stopped at several of the following major stopover locations. Each of these refueling stations is visited by 1,000,000 to 1,00,000,000 shorebirds each spring. Can you find them on a map?
Stopover Site..........Location
Estero Rio Colorado.......Baja California, Mexico
San Francisco Bay.........California, USA
Columbia River Delta......Washington , USA
Willapa Bay...............Washington , USA
Grays Harbor..............Washington , USA
Fraser River Delta........British Columbia, Canada
Stikine River Delta.......British Columbia, Canada
By April 28, the 30 Western Sandpipers that were radio-tagged in San Francisco had been detected in Willapa Bay, Grays Harbor, and the Fraser River Delta. These birds were tagged between April 17-22.
Twelve of 20 Western Sandpipers were radio-tagged at Honey Lake in California on 25 April. On May 11, one of the Honey Lake birds was detected at Copper River Delta in Southeast Alaska.
No shorebirds have been spotted on the North Slope of Alaska yet. As soon as we get news of their arrival we will let you know!
If you would like to continue to track the "Super Shorebird Highway" or add some of your own field trip data, you can access the Shorebird Sister Schools Program here.
Or
send an e-mail to: heather_johnson@mail.fws.gov.
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