American Robin Migration Update: April 13, 2004

Today's Report Includes:

• Latest Migration News: Proclaiming Territories and Nesting
• Claiming a Territory: “New Kids on the Block” Video Clip
• Robin Hood’s Mate Returns! Meet Maid Marion
• Watch Out for Flying Balls of Litter! Robin Watcher's Checklist
• Nest Building 101: Link to Lesson
• Weighty Stuff: Challenge Question #8
• Tracking Temps and Robins: Compare This Week’s Isotherm Map
• News From the Northern Observation Posts (NOPs)
• That's the Limit! Journaling Question
• Listening or Looking? Discussion of Challenge Question #6
• Robins Finding Earthworms: Link to Lesson and Journaling Question

Latest Migration News: Proclaiming Territories and Nesting

Spring is spreading as robins push steadily into Canada and points north. As the map and data on the web show, robins—-males AND females-- are still arriving from coast to coast. A few are singing and proclaiming territory at least as far as 50 degrees north, even in places where it’s still snowy and cold! Looking at the map, do you think the peak of migration has passed for first robins seen? Please continue to report your robins to help us track the migration all the way home! Read on to hear what’s been happening where robins have arrived.

Claiming a Territory: New Kids on the Block Video Clip/Viewing Guide
Ms. Sussman from grade 4 at PJ Kennedy School in Marblehead, MA wrote: “Observed 3 robins: appeared to be 1 adult (larger) and 2 juveniles. The 2 juveniles were bantering in the air (like a squabble) and then separating to the ground to feed on grass seed... repeating this behavior over and over. Or was it a mating ritual?” Good question, and we think you’ll be able to answer it yourself after viewing a video clip with guidance by our expert, Laura Erickson.

The first year a bird tries to find a territory, it takes a while and a lot of exploring to find an open territory and then defend it against other young birds. Laura Erickson watched a couple of young males when she was in Nebraska in March. They had separated from the big migratory and feeding flocks, and seemed to be interested in establishing a territory for the first time. The problem was, they both picked the same place! They were used to being with lots of robins, and now they didn’t know what to do to make the other robin go away. See their behavior for yourself with Laura’s video. She helps you understand what you are seeing, and you’ll know what she means when she compares it to playing basketball. When they’re robins, what are things like for “new kids on the block?”

• New Kids on the Block (Clip, viewing guide, Journaling Questions)
  

Maid Marion, mate of Robin Hood. Photo Julie Brophy

Julie points out one distinguishing thing about Maid Marion in her field notes. Can you find it before you read those notes?

Robin Hood’s Mate Returns! Meet Maid Marion
Last time you met Robin Hood, an American Robin who has returned to the same territory for the fourth spring in a row. His territory is the backyard of Journey North’s Julie Brophy. Julie knows “who’s who” in her backyard, and now she tells us that Maid Marion is back! What’s Maid Marion’s story? What Robin Hood behaviors led Julie to think his mate was back too? What questions did Julie ask herself to be sure she was really seeing Maid Marion, and not another female robin? Julie shares her field notes with us. Look for Julie to describe 3 differences between male and female robins. And find out an unusual clue about Maid Marion’s appearance!

• The Story of Maid Marion
  

Watch Out for Flying Balls of Litter! Robin Watcher's Checklist
“Robins courting and checking out possible nesting sites” was the news from Lexington, MA on April 9. And on April 3 in St-alphonse-de-granby, PQ, our observer said, “The robin has started building the nest.” Hooray!

Females are arriving in many places. How can you tell when nest building begins? Watch for males and females flying with nest materials, and for females with mud on the breast feathers. Females may begin nest building within a day or two after arriving. For your own field checklist of other nifty robin events to watch for, see:

• Robin Spring Phenology Checklist
  

The female is the main builder, but her mate helps by bringing her nest materials. When building their nest, Mr. and Mrs. Robin can often be seen carrying huge loads of nest material. Bird expert Roland Wauer wrote, "One female robin at Curecanti National Recreation Area, Colorado, was so loaded down that her package of twigs and grass doubled her head size; she looked like a flying ball of litter."

Building a nest normally takes 4 or 6 days, but can take up to 20 days in bad weather. What if the nest is destroyed? The female may rebuild it in a single day. Later broods may be raised in the same remodeled nest, or the female may build a second nearby nest in 2 or 3 days. More than half of the second broods are raised in nests built at a new location. No wonder nest building keeps our robins so busy!

Who decides where a nest is built? Of course, robin watchers don't get a vote. The final decision is pretty much up to the female, and some females have a hard time making up their minds. They may start two or more nests before settling on a single site. Experienced females might repair an old nest, or build a new one on the old foundation. Some bird experts say that as many as six nests have been build on top of another.

Nest Building 101
Robins don't need written instructions for building their summer homes. They follow the "nest-building blueprints" in their brains. They instinctively know how to build the perfect structure to hold the eggs they're about to lay. Have you ever noticed that robins' nests are always alike? But have you ever seen a robin teaching another how to build a nest?

Imagine you are a robin. What makes a suitable building site for your nest? What materials will you use? How do you build a nest when you don't have hands? Why do you, the parents, sleep on a nearby branch after the first week, except when it rains? Why do you move out and build a new nest after the babies leave? You'll get help with these answers along with step-by-step instructions for building a robin's nest with this terrific Journey North lesson:

• Build a Robin's Nest!
  

Teacher Tip: Reading and Writing Connections
Introduce the selection by asking students the following questions:
1. How do robins build a nest?
2. What kinds of natural materials do robins use to build their nest?
3. Where do robins build their nests? Why?
4. How big is a robin’s nest?

Create a chart to organize questions about a robin’s nest-making process. Write the topic on chart paper: A Robin’s Nest-Making Process. List five categories below the topic: Who? Where? When? Why? How? Use the chart prior to reading the selection to record students’ questions and predictions. (Activating Prior Knowledge, Making Predictions and Asking Questions to Set a Purpose for Reading)

This tip is from Journey North’s Reading and Writing Connections. For the complete lesson for this short nonfiction selection, click here.

Weighty Stuff: Challenge Question #8
As you work your way through this week’s report, you’ll learn a lot about robins and their nesting behaviors. You’ll have the facts to reason out the answer to this week’s Challenge Question. Start by looking at these American robin weights:

Average Weights in Grams	Winter Male	Breeding Male	Winter Female	Breeding Female
American Robin	86.2	84.8	83.6	75.0

Challenge Question #8:
"Which are heavier: winter robins or breeding robins? Which loses more weight in spring: male or female robins? Why do you think this is?"

(To respond to this question, please follow the instructions below.)

Tracking Temps and Robins: ComparingThis Week’s Isotherm Map
Are you tracking the isotherm with YOUR robins? Here's a comparison between this week and last time:

March 27 Map	April 10 Map

1. Has the 37-degree isotherm moved in the past two weeks?
2. Have robin movements shown a pattern similar to the change in the 37-degree isotherm? (Compare with the migration maps at the top of the Web report.)
3. Do the changes in where the 37-degree isotherm is correspond to where robins have been singing?

For instructions to calculate the isotherm in YOUR region, see:

• Fever: Testing a Temperature Theory About Robin Migration

News From the Northern Observation Posts (NOPs)
Despite some recent blasts of winter, robins are appearing and even singing in the far north. In our Northern Observation Post at Beresford, NB, Canada, lucky Marc Landry was delighted to report April 9 that “The spring symphony was in town!” Grade 4 teacher Linda Miller at St. Mary of the Lake School in Widewater, AB (latitude 55.22N) said, “Two students first saw robins April 8--One in Widewater and one in Slave Lake.” But what about in Anchorage, our official Early Bird Contest outpost? Just see how teacher Mike Sterling describes their winter and you’ll probably adjust your prediction for the first robin there. (That was Challenge Question #4, and you still have time to send your answer!) See the news from the NOPs, and continue updating your NOP predictions/results logsheets:

• News From the NOPs for April 13, 2004

This range map shows the northern limits of robin nesting territory. As we've watched robins migrate many miles across North America over the past several weeks, can you help but wonder?

Journaling Question:
"Why don't robins go even farther north? What factors influence the northern limits of their nesting range?"

Listening or Looking? Discussion of Challenge Question #6
We asked, "When a robin hunting for food cocks its head, do you think it's listening or looking?" Most of you thought the answer was BOTH.

“When a robin cocks its head, it is listening for other animals that might be lurking. It is also probably listening for the sound of food, like bugs or any different sounds under the earth. I also think that it might be looking for food and predators,” said Daisy, Grade 4, Ferrisburgh (Vermont) Central School

Iselin Middle School 7th graders agreed. Brett, Najea, Mellisa, and Richard said he is listening and looking for predators, and also looking for food. Shivam, Justin, Javed, Gabriel, and Eliott said, “We think they are looking because the earthworms are out now and they are constantly looking at the ground. They might be listening for vibrations in the ground to detect where the earthworms are.”

Do you wonder how robins actually DO find earthworms to eat? Read on...

Journaling Question:
If you had the materials Frank Heppner used, how would you design experiments to prove which sense(s) robins use to find worms? Why do you think he used each of these materials?

After you write your answer, see what some savvy fourth graders thought, AND what Dr. Heppner concluded. Find it here. (Then go tell robin-watchers what you discovered!)

• Which Senses Do Robins Use to Find Worms? Dr. Heppner's Experiment
  

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 #8.
3. In the body of EACH message, give your answer to ONE of the questions above.

The Next Robin Migration Update Will Be Posted on April 20* (Migration Data Only.)

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