American Robin Migration Update:
April 12, 2005
American Robin Migration Maps and Data
Initiation of "Song" is the clearest pattern we expect to see as we track the spring robin migration. Printer-friendly format: Latest Migration News ”As I walked into school, I heard the cheery notes of a robin coming from a tall pine tree. What a way to start the day!, said an observer from Auburn, Indiana. In Stanhope, NJ, on April 5, Mrs. Ference from Byram Lakes School reported “about 40 robins hopping across the grassy ground pecking at the soil and plants. It was about 8 AM and a bright, sunny morning with a temperature of about 45 outside. We'd had a weekend of rain, so I think they were hunting for any insects or worms coming up out of the ground.” On the same day, Derek in Marquette, Michigan, saw a group of five Robins in town. “They were patrolling the edges of the road where most of the snow had melted.” And in Canada, waves of robins arrived in several places. A look at the map shows that robins are making steady progress northward. More robins have crossed the border into Canada--where some are also singing! From week to week, do you see a beautiful migration pattern emerging? And on the “first seen” map, where is that robin waaaaaaay up in northern Alaska? (Look carefully and you’ll see it’s on a yellow star, one of our Northern Observation Posts.) Go, robins! While we're waiting for robins to reach the end of the migration trail, the breeding cycle is underway in places where robins have already arrived. Courtship, nest building, egg laying, incubation, and care of the young all take place so robins can make more robins. Or, as scientists say, "pass their genes on to the next generation." Here’s a challenging question:
Working on the CQ above might make you wonder some other things about laying eggs and raising robin babies. Who do you think does more work in raising young, the robin male or the female? Which robin takes more risks, the male or the female? Which robin would you rather be: a male or female? Why? You'll be able to answer these questions a lot better after digging into the pages we've made to help you collect clues and sort facts: When you know the story behind the eggs, come back and answer:
(To respond to this question, please follow the instructions below.) Early Bird Contest (CQ #4 Reminder) and News From the NOPs
Spring Comes to Alaska: Challenge Question #10 Joy Hamilton of Innoko River School in Shageluk, Alaska, shared photos to show you what spring is like in her part of the biggest US state. You’ll see lots of snow, and also their first robin! Laura Erickson, our robin expert, took a close look at the Shageluk robin and said, “You can tell this adult male robin arrived in excellent condition for the breeding season. I can tell he's healthy because of three things.” Read Laura’s list and look for the evidence in the photo.
(1) His feathers are in perfect order. (2) He looks plump. (Unlike humans, birds burn up body fat very easily and don't lay fatty deposits on heart tissue.) (3) His eyes are bright and interested. His good health and extra body fat will enable him to give almost all of the food he finds to his hungry babies in a few weeks! Challenge
Question #10:
Answers from the American Robin Expert, Laura Erickson Will a pair of robins use their nest from the previous year? Why is a robin flying against my window repeatedly? Why do Robins migrate? See how American Robin expert Laura Erickson answers these and other questions as we unveil the answers for your 2005 “Ask the Expert” questions. There’s a lot to learn from your good questions and Laura’s good answers! Thumper is Back: Help for Window Bonkers “ He's BAAACK!” writes Cindy from Grant, MN. “Last year we had a male robin constantly fly against our dining room window to defend his territory from...himself! (My windows are not that clean!) We call him Thumper and he is doing it again this year.” Plenty of people have the same problem as Cindy. Are you one of them? Here’s help:
Field Study: Listen to the Robin “This morning there were robins all around (not visible) but certainly
audible. The robins seemed to be singing two distinct songs. It's a lovely warm
day and
the robins help us truly know that spring is here--that
spring is really here.” Beloit,
Wisconsin observer If you wonder if your females are around yet, these tips may help you: Thanks, Rachel Carson!
Journaling Question Birds of a Different Feather: Visualization and Journaling
Try This! Visualizing and Journaling
Tracking Temps and Robins: This Week’s Isotherm Map We’ve invited you to test the theory that robins follow the 36- or 37-degree isotherm during migration. (The isotherm is an imaginary line that connects places having the same AVERAGE temps.) So, how’s the theory holding up in YOUR region?
Robins,
Temperatures, and Tulips: Discussion of Challenge Question #6
Hooray for Richard, Sayantan, and Shivam of Iselin (New Jersey) Middle School/7th grade, who indicated that the temperature is indeed the key. What role does the geography of North America play? The oceans along the coasts have a moderating effect on the temperature. From the maps, you can see that "spring" moves up the West Coast more quickly than it moves up mid-continent--all the way to Alaska. The robin migration (and song) should follow the same pattern, with those in mid-Continent arriving (and singing) much later than those on West Coast at the same latitude. Numbers of Nests: Discussion of Challenge Question #7 Last time we said that robins nest three or even four times a season in most places in the US and southern Canada. Even in the northern parts of their range, robins usually nest at least twice. We asked, “Why do you think robins nest so many times during a summer?” Robins must produce plenty of babies to keep the robin population high enough to replace all the robins that are killed each year by hawks, cats and other predators; pesticides;, accidents; ice storms and other bad weather; and all the many other hazards they face. And many robin nests fail. Robin nests are fairly conspicuous--that's why we're lucky enough to see robin nests more often than most other birds' nests. But that means they're also pretty easy for jays and crows to discover, and jays and crows feed robin eggs and nestlings to their own hungry babies. With so many dangers, robins need to produce a lot of new babies each year. If a pair nests successfully four times in a year, they're likely to produce about 15 babies (4 each in the first three nests, and 3 in the last one. Sometimes the third or fourth nestings can have only one or two eggs.) But most robins don't succeed with four nestings in a row. It's a lot of work keeping a species going! How to Respond to Today's Challenge Questions: Please 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 (OR #9 OR #10). 3. In the body of EACH message, give your answer to ONE Challenge Question. The Next Robin Migration Update Will Be Posted on April 19*, 2005. (*Data only)
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