American Robin Migration Update: February 29, 2000 Today's Report Includes:
Calling All Robin Watchers So please continue to watch for and report:
Robins Reach Home! Notice how few robins are singing in the north? With your help, we can document each robin's arrival at the end of the migration trail. Please report to Journey North when:
Today's Migration Data You can make your own map with the data above, or print and analyze our maps. A Harbinger of Spring--or Just a Hungry Bird?
During the nesting season, a brood of robins will eat 3.2 pounds of food during the 2 weeks they are in the nest. By its last day in the nest, a young robin may eat 14 feet of earthworms! After reading about what robins eat, see if you can answer... What's on the Menu?
More Food For Thought
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respond to these questions, please follow the instructions below.) Telling Time by Robin Behavior Discussion of Challenge Question #1 In our last Update, observers reported robins behaving just as is expected during the winter months. However, the Robin's behavior during the breeding season is quite different. The changes are so obvious that you could identify the season by simply watching behavior. Challenge Question #1 asked, "Which things would you NOT see during the breeding season? Why?" During the Robin's breeding season, you would not ever see robins in broad daylight "evenly spaced about 3 feet apart", or groups of "10 to 20 robins in every tree" or in "a large flock of 100 flying together overhead". During the breeding season, robins spend all their daylight hours on--and busily defending--their nesting territories. (One exception: Male robins are known to form overnight roosts year-round, even when they are defending their nesting territory during the day. Author Roland Wauer points this out in his book, "The American Robin" (Copyright 1999).) Next, the feeding observations. Comments like these are observations that wouldn't be typical in the breeding season:
Why? During spring and summer, robins hunt on the ground. They feed in places where earthworms and insects thrive in rich, moist soil. In fall and winter, they switch to berries and other fruit they find on a variety of shrubs, trees, and vines. Try This Over the next several months, create a list of robin behaviors you observe. See if you can separate the observations into (1) breeding season (2) non-breeding season and (3) year-round behavior. How did you reach your conclusions? Include those comments. Which behaviors seem most difficult to categorize by season?
Whose Robins Might These Be? Discussion of Challenge Question #2 In our last update, an observer in Montgomery, Alabama saw trees filled with very feisty, pre-migratory robins. "There were 10 to 20 robins in every tree you looked at--it looked like a robin festival," she said. Challenge Question #2 asked, "Where might robins that winter in Alabama and Georgia go to breed in the spring?" These robins may go to Vermont, Pennsylvania, Massachusetts, New Jersey, New York, West Virginia, Michigan or Maryland--to name a few possible places. How do we know? We used banding data from real robins. These robins were "recovered" during the winter in Georgia or Alabama, after being banded during the breeding season. Follow these step-by-step instructions to find the answer. How to Respond to Today's Challenge Questions IMPORTANT: Answer only ONE question in each e-mail message. 1. Address an e-mail message to: jn-challenge-robin@learner.org 2. In the Subject Line of your message write: Challenge Question #4 (or #5) 3. In the body of each message, answer ONE of the questions above. The Next Robin Migration Update Will be Posted on March 7, 2000.
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