American Robin Migration Update: March 18, 2003
Today's Report Includes:
It's Great to be Back! This Week's
Maps and Data
People are seeing, and hearing, robins more and more, thanks
to the beautiful, warm weather that has hit many places this week. Patricia
Decker reported seeing them in Cropseyville, New York, on March 13 despite
over 12 inches of snow on the ground. Alberta Sweet reported "Two
very ragged looking robins sitting and singing high on a poplar and spruce"
on March 13 in Calgary, Alberta.
A Sound for Sore Ears
More and more robins will be singing in the coming days and weeks. If you're
hungry to hear one right this minute, listen, courtesy of Lang
Elliott, right here:
Once your robins arrive, you'll be hearing more than singing--they'll
make alarm calls, flight calls, and other sounds. Learn how to recognize
and understand them here:
Then answer these questions:
Challenge Question #5:
"Real robins don't have dictionaries. How do you suppose robins
learn what each of these sounds means?"
Challenge Question #6:
"Which robin vocalization is most likely heard just before
the sun rises? Which is heard more often at noon than any other time?"
(To respond to these questions please follow the instructions
below.)
A Sight for Sore Eyes
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This flock of robins is still migrating.
When robins start singing, they're usually settling down in a
territory, and aren't so close to other robins.
Photo by F. Ludwig
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Ken McIlwrick saw a few thousand robins all
around Vancouver, British Columbia, while he was visiting there between
March 8 and 12, 2003. He also heard robins singing in many places in the
city. What Ken had found was both a huge migration wave--robins
taking a break in Vancouver before moving on--and also robins who had arrived
at their final destination. The migrating robins were probably a little
stressed out hearing so many territorial birds, but they instinctively realized
that it wasn't quite time to be heading up to their own territorial areas.
How does your own backyard, and your schoolyard, look to robins from
up above? We humans look at the world from our vantage point a few feet
above the ground. Robins see just about everything from different angles
than we do.
For example, we see our own back yard from eye level or from the porch
when we're outside, and from looking out our windows when we're inside.
If we sit outside in a lawn chair, we see things a little differently.
Imagine if we saw our yard from the top of the tallest tree around, from
within a thick shrub, from three inches above the ground, and from the
air while flying above the treetop. What might robins notice that we usually
don't see? Read about it here:
Then think about this question:
Challenge Question #7:
"Working together with classmates, list at least 10 clues
robins can see or hear from above that tell them about the territory
down below."
(To respond to this question please follow the instructions
below.)
Do
Robins Really Follow the 37-Degree Isotherm?
Have you been trying to learn whether robins follow the 37-degree isotherm?
Look at the maps below and answer these questions:
- What color is the part of the maps showing the average 37-degree isotherm?
- Has the 37-degree isotherm moved in the past 2 weeks?
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Average
Temperature in United States Week of February 23-March 1, 2003,
and Week of March 9-March 15, 2003. (No map available of entire
continent.)
What color is the 37-degree isotherm? Have robin movements shown
a pattern similar to the change in the 37-degree isotherm?
Photo Courtesy of NOAA
Climate Prediction Center. |
Compare the changes in where the 37-degree isotherm is to where robins
have been singing by looking at the robin migration maps above. When you
compare these maps, do you think the migration is following the isotherm?
News
from the Northern Observation Posts
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This is how
things look in Beresford, New Brunswick--photo by Marc Landry, NOP
Observer |
Are you wondering if students at Sand Lake
Elementary School in Anchorage have seen their first robin yet? (Remember
the Early Bird Contest is Challenge
Question #4.) On March 13, Sand Lake Teacher Mike Sterling reported,
"The sun came back, and ironically the temperatures dropped to some
of the lowest we've seen this winter. Last week we were watching moths
and mosquitoes; this week we are battening down the hatches as near zero
degree temperatures combine with powerful northerly winds and pound us
into submission. Pity the poor robin that would choose this week to appear
in Anchorage. Bottom line: we haven't seen any robins."
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Northern Observation
Posts 2003 |
Check your predictions and keep up to date with news from the NOPs here:
Ask the American Robin Expert
Are you wondering something about robins?
Ask the expert! Submit your questions for Laura Erickson by our deadline,
Noon Central (or 1 pm Eastern time) on March 28, 2003 to
Answers from the American Robin Expert will be posted on April 11, 2003
Switching
Diets: Discussion of Challenge Question #3
Last time we asked you to "List at least three different
environmental clues that might tell robins it's time to switch from eating
fruit to worms." Here are some we thought of:
- Changes in daylength might trigger changes in feeding patterns.
- Changes in weather might trigger changes in feeding patterns.
- Not many berries left.
- Old berries starting to dry up and taste junky.
- Sight of bare, moist ground might trigger robins to search for worms.
- Worms wiggling on the surface might seem (to a robin) to be saying
"Eat me! I'm yummy!"
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 #5 (OR #6 OR #7).
3. In the body of your message, give your answer to ONE of the questions
above.
The Next Robin Migration Update Will Be Posted on March
25, 2003 (data only).
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