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FINAL Robin Migration Update: May 19, 1998 Today's Report Includes:
FINAL Robin Migration Map Thanks to everyone for helping to build this picture of the robin's spring migration. We hope you'll join us again next spring for the robin's last migration of the 20th century.
Robin Research: Suggestions for Summertime Robin Watching
Robins can sing for long stretches without stopping. We need to pause to take a breath now and then when we are singing or speaking. This is because our sound is only produced as we breathe out--but birds can make sounds while breathing both in and out.
When you hear a robin making a sound, try to discover what that call means. Robins have one alarm call when
they notice hawks and another for ground predators. They make a different sound when they discover a cat near their
nest than when they discover a nearby human. If possible, tape record your robins. How many different calls can
you hear? Some ornithologists have described various robin calls as "teek," "tuk-tuk," "teacheach,"
and "eee." How would you describe the calls you hear?
their young for as long as you can. For each nest, answer as many of the following questions as you can:
Both the male and female robins who "owned" that territory spent a lot of time chasing them away at first, but when the female started incubating her eggs, she stopped chasing off the other females. The male kept chasing off the other males until the babies hatched--then he had to spend so much time searching for food for them that he stopped chasing off the others unless they started exploring away from the bird bath. As long as they flew along the shortest possible line from their territory into the birdbath, he left them alone, but if they veered off that path for just a few seconds he'd charge them! By studying where each robin spent the majority of its time, where it could be with the others ignoring it, and where it was when disputes took place for several weeks, the woman had a clear picture of where each robin's territory was, and she could have drawn a simple map with each "territory" outlined. Draw a map of a small part of your neighborhood. Mark in the trees, bushes, houses, fences, and other things that robins might notice, and mark any robin nests you find. Use this map to study the robins in your neighborhood for a week or two. See if you can start recognizing different individuals, and where they each spend their time. Give each bird a letter, number, or symbol. Mark a bird's symbol in the right spot on your map every time you see it. Do they spend more time in some areas than others? Can you draw territorial boundaries based on where they spend their time? Set out a bird bath or a bowl of water or a lawn sprinkler. How long does it take for robins to notice it? Does the water attract robins from other territories? How do the birds work out their "water rights"? Robin Behavior Study Some birds can only hop on two legs; others can run or walk. During a 10 minute observation period, how often do you see robins hopping? Do you ever see them walking? Before, during, or after robins make some calls, they move their bodies in a particular way. These are called visual displays. See if you can observe any visual displays. Draw the robin's shape while doing these. Ornithologists still debate about how exactly robins locate earthworms. Do they see them in their underground tunnels through the airholes? Do they feel vibrations of worm movements with their feet? Are they listening for them? Watch robins feeding, and the moment one flies away, study the ground where it was. Can you see any earthworm tunnels? How do you think they find their food? Robins and Pesticides Study Are any of the yards in your neighborhood treated with lawn chemicals? If you can, get permission from your neighbors to study the robins in each yard. Find as many robin nests as you can. Compare how many are in treated and untreated yards.
This is the FINAL Robin Migration Update. See You Next Year! Copyright 1998 Journey North. All Rights Reserved. |