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Bald Eagle Migration Update: March 23, 2005 Today's Report Includes:
Today’s Map and Data
A
quick look at our map this week and you can see more birds have been
added to our study! Welcome to fledglings Y89, Y90, Y94 and Y96. Join
us in comparing and contrasting the behaviors of these New York state
nesters with our migrating bald eagles.
Field Notes from Peter Nye Greetings Weekly Eagle Trackers: It appears that spring is indeed in the air, and that our eagles (most of them) have taken notice. Our newest capture, adult male bald P04, continues on his way north, albeit apparently not in any huge hurry. During the week, he appeared to be very close to where I live, and by the end of the week he was just to the north of Albany in the Adirondacks near a place called Speculator. We'll have to see how far and fast he will ultimately go. Our other adult bald, V98, remains on the Aberdeen Proving Ground in Maryland. We grow more worried about her by the day, and I have been in contact with Maryland eagle biologists about her. I have forwarded them her radio frequency and will be shortly sending them a radio receiver to see if they can "track her down" on the ground and see what's up. Included here, for the first time, is data on 4 yearling bald eagles we radio-tagged as they left their nests in New York last summer.
You will
see where they wintered, and you will also see now where they are headed;
3 of the 4 appear to be moving north, away from their wintering sites
and (I believe) back toward their natal areas. (look up "natal"!).
Biologists have long believed that young eagles move back to their original
fledging areas as yearlings, likely simply as a "re-orienting"
lesson, to tell themselves, "yes, this is where I came from"
(kind of like kids who come back home after college ??). Then, when
they reach sexual maturity at about 5 years of age, they will select
their own nesting sites somewhere "near" their natal area,
a process known as "fidelity". We will learn a lot from these
satellite-tagged youngsters, and see just how much of what we think
we know, is actually true!
The NY fledglings outfitted with satellite transmitters while still in their nests give us a great opportunity to gather information on behavior and essential habitat use. In contrast to the "winter visitors" that come to NY each winter from points in the far north (to take advantage of all our open water and fish throughout each winter) the fledglings are "locals." However, both groups can be considered migrants (("Migrants" means that the eagles move seasonally for feeding or breeding.). Try This! Divide the class into 4 groups with each group adopting a fledgling. Learn where each young bird's nest is located. Describe where the bird spent the winter (starting early Feb.) and determine whether there has been any movement toward their natal area. Just For Fun After gathering all the information about your fledgling, brainstorm possible "nick-names" for your bird. What name best reflects each birds characteristics? Compare and Contrast Transfer the information collected about each fledgling to the Compare and Contrast chart. Keep the chart handy as we follow the fledglings through the season. Eagles on Eggs (on Camera)
You can't hop into Pete Nye's helicopter for his nest survey, and you can only imagine what's happening in the eagle nests. But thanks to technology, you can take a peek inside one Bald Eagle nest any time you want. The "Eagles Online" Webcam, sponsored by Northeast Utilities, sends live shots from a Connecticut River Bald Eagle nest, where egg #1 is about 3 weeks old.
Measure and compare a chicken egg with an eagle egg. How does their size and shape compare? Field Notes by Remote:
Bald Eagle Adaptations: The Tail
Are you ready for this week's adaptation? An eagle's body is adapted for its fishing and scavenging lifestyle.
(To respond to this question, please follow the instructions below.) V98 Puzzler Solved
We asked you to calculate this using a simple formula. Here's how far V98 flew on the first few days of her migration in 2004:
Thanks to the math whizzes at Iselin Middle School/7th grade: Ikadshi, Vaidehi, Shreyas and Sarah. This number is approximate. Can you figure out why? Eating Out: Discussion of Challenge Question #10 Imagine being an eagle for a minute. We began last week to learn about the food that is required for the eagle to survive. Here was our question: "How many pounds of food does an eagle need to consume each day? If you needed the same percentage of food daily, how many pounds would you need?"
Male bald eagle would need 0.51.4 lbs of food each day Humans 80 lb person would need to eat 4-8 lbs of food each day 100 lb person would need to eat 5-10 lbs of food each day 120 lb person would need to eat 6-12 lbs of food each day Thanks to students at Iselin Middle School/7th grade, Bhavini, Bridget, Michael and Ihtisham. YIKES! Could you eat that much food in one day? The eagle eats so much more for its body size than we do! Why? Eagle Expert Answers YOUR Questions Thank you for all your excellent questions for Eagleye Nye! Each year brings more interesting questions. You can read all the questions and answers for this year. Visit: Eagle Head Adaptations: Discussion of CQ #11 The eagle's whole head is designed for its fishing and scavenging lifestyle. Last week you took a close look at their head and shared what you learned. Here are some of things we heard:
Read for more information about these adaptations. Eagle Glossary Build your vocabulary with terms used in our reports as we study eagles this season. Find the following terms from this week’s report and define them in your eagle journals or portfolios: natal, fidelity, scavenger.
How to Respond to Today's Challenge Questions:
1. Address
an e-mail message to: jn-challenge-eagle@learner.org Copyright
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