Migration Over The Brooks Range

28 May 2014 by Liz O'Connell, posted in Migration

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Even Wacky Weather doesn't stop bird migration to Alaska. Scientists on the north side of the Brooks Range at Toolik Field Station find the birds which made it over the mountains have located their nests, indicating procreation has begun.

Simone Meddle, associate professor at the University of Edinburgh, outlines new discoveries suggesting migrant visitors may turn off their physiological stress response in order to breed successfully in the hectic Arctic weather.

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“Our studies have shown that these Long Spurs are able to turn off their stress response. And their sensitivity to stress hormones is very much reduced once they have established territories, once they have built a nest and are breeding on the tundra. They tenuate their stress response and the specific part of the brain – the paraventricular nucleus in the hypothalamus very deep within the brain – is able to become insensitive to stress hormones.”

“We know that these birds switch off their stress response, we understand its specific part of the brain, but we now want to find out how they integrate these environmental cues to do that.”

Marilyn Ramenofsky, adjunct professor at the University of California Davis in the Department of Neural Biology, Physiology and Behavior, is another scientist working to decode migratory bird behavior in Alaska. She recognizes birds’ abilities as she chats about past studies investigating small migratory birds called White Crowns.

“[Scientists] wanted to know: if you displaced White Crowns to the East Coast during fall migration, would the adults know they were on the East Coast and make adjustments to come back West before they headed South? And would the juveniles do the same? Earlier studies … showed that juveniles can’t make adjustments. They just follow the plum line – they just go South – whereas the adults can make these adjustments.”

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“They have cognitive maps, and they can read North and South; it’s not a problem. The juveniles will head straight South. The adults will be able to manage, make alterations if need[ed].”

“They were released separately and the adults tried to come West, so they are reading, probably, magnetic fields. They are really good at reading celestial cues, solar cues, polarized light...”

As the summer season progresses, Arctic full bloom is on, meaning the multitude of bugs which feed on thriving plants have hatched. Graduate research assistant Ashley Asmus of the University of Texas at Arlington visits Toolik Field Station in Alaska to collect and document the insect explosion that provides a vital buffet for migratory birds. If the reverse leaf blower she uses to collect the bugs surprises you, so will the variety and quantity of insect life.

Find these four short videos: Wacky Weather, Birds Over the Brooks Range, Where are the Nests and Bugs and Birds on the FrontierScientists.com web site. Later, check back to FrontierScientists to watch the upcoming video Birds and Their Backpacks about tracking far-fliers, which will complete our latest video series about Bird Migration in the Arctic.

The scientists, students, and citizen scientists describing their work in these video links include: Rick Thoman, Nancy DeWitt, Marilyn Ramenofsky, Jesse Krause, Kathleen Hunt, Ashley Asmus, Jonathan Perez, Bob McCoy, and Chris Fallen.

Migration project

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HAARP is the High-Frequency Active Auroral Research Program facility near Gakona, Alaska. The Air Force plans to shut the facility down. Join scientists in a letter writing campaign; you can ask to your congress representative to save this facility. For more information, read May 21, 2014 opinion in the Anchorage Daily News titled Save HAARP, save money, save science by Dennis Papadopoulos, professor of physics and astronomy at the University of Maryland.

Liz O'Connell
Frontier Scientists: presenting scientific discovery in the Arctic and beyond

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