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Program #5153 of the Earth & Sky Radio Series with hosts Deborah Byrd and Joel Block download Help Sandhill cranes breed in the marshes and bogs of North America and northeastern Siberia. The Platte River at the edge of Nebraska's Sandhills is an important stopover for up to 450,000 of these birds during migration. (Photo by FortPhoto) In our human world, we’ve become stewards to many animal species. Among the most beloved are the migratory bird species that travel great distances across the globe. Howell: Where do birds come from and where do they go? That’s a fundamental question that’s intrigued scientists and people from the beginning of time. That’s Judd Howell, director of the U.S. Geological Survey Patuxent Wildlife Research Center. Howell told Earth & Sky that bird tracking technology has come a long way. Once upon a time, satellite transmitters were so heavy that only big animals like polar bears could be fitted with them. The bears could be tracked to within several kilometers. Now, birds the size of geese or ducks can carry the transmitters on their global treks, and they can be tracked to within a few meters. Howell: If we understand what their habitat needs are – a habitat is the place where an animal lives, it gets its food there and its shelter there and it reproduces there – if we can understand what those needs are and make sure that those needs are being met then you can be reasonably assured that you’ll be able to keep that species going in the wild. Practical applications for humanity include monitoring where wild and domestic birds meet. Howell said one such program in China relates to the spread of avian flu. Our thanks today to NOAA – the National Oceanic and Atmospheric Administration. |
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