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Robin Migration Update: March 24, 1998 Today's Report Includes:
Today's Migration News & Data
March 17 "We saw our first robins here in at nearly 9000 feet above sea level," reported students at Crested Butte Community School in Crested Butte, Colorado. "We only saw some small groups so we will keep our eyes open for big flocks. We had some really warm weather and a lot of our snow melted but it is snowing again today so we hope there is some other food besides worms for our robins." (bpogoloff@tomichi.ghs.gunnison.k12.co.us) On the same day, students at Emerson School in Ann Arbor, MI reported: "Today at 8:00 AM we saw our first WAVE of migrating robins. It is a clear, cold day, about 27 degrees. They were on our playground. They were very jumpy; they moved quickly and didn't settle. They hopped around, and flew from bush to tree to pavement. We counted 21! It is now 9:00 andthere is no sign of them." (webercb@hotmail.com)
* Reminder: There is often a delay between the time people SEE their first robin and the time they REPORT it. Therefore, remember that these data are a summary of all sightings REPORTED since the last update.
Robins on the Road Journey North Robin Expert Laura Erickson met up with the robins as she traveled southward through the Midwest. "The vast majority of robins are still hunkered down in the middle of the country, waiting for warm temperatures to thaw the ground," says Laura. "I spent the first day of spring in Nebraska, watching huge numbers of early migrants. I already knew that close to a half million Sandhill Cranes spend the month of March along the Platte River--watching them was the reason I came to Nebraska. But I wasn't expecting all the robins! There were flocks of them everywhere--some of ten or fifteen birds, but some with hundreds. One group that passed over the road just in front of my car had at least four hundred robins! Although people have been spotting robins as far north as Maine and Ontario already this season, some overwintering, the vast majority of robins are on the road --and I got to see a LOT of them in Nebraska! "That whole week had been cold, with freezing drizzle and temperatures mainly in the twenties, making some kinds of food hard to find. Robin flocks moved about, sometimes all landing on a cornfield together, reminding me that the early robin doesn't always get the worm--the fields were too frozen and snow- covered still to have many worms near the surface. Sandhill Cranes in those same fields were finding plenty to eat, because they eat the waste corn that spilled during last year's harvest, but robins apparently don't like frozen corn. "Most of the flocks I saw were either flying around, perhaps trying to find new sources of food, or sitting in crab apple trees, eating last summer's leftovers. I studied a few groups closely, and could only find males. Usually females stay in the south for a few weeks longer than males, since they aren't responsible for establishing a territory. Females may also hold back to make sure their bodies are well-nourished for the important job of egg-laying when they do arrive. It's lucky these males weren't facing the job of laying 4-6 eggs in a few weeks, because they seemed very hungry! "They also seemed restless. Most of the robins I saw weren't feeding, but flying about in their flocks. Even though the temperature wasn't quite up to the average 36 degrees they need to migrate, longer days were telling something deep inside them that it was time to go. After I left Nebraska on my 731 mile drive home to Minnesota that first day of spring, I didn't see any huge robin flocks, but did spot six little groups of three and four here and there along the highway in Iowa, and a couple more in southern Minnesota. "If we have another bad winter storm, some of these early birds may have to retreat south again or even die. Migrating ahead of the main flock is risky business. But the ones that do reach their breeding grounds first will be richly rewarded with the choicest territories. It's a gamble, but that's nature's way." Announcing the 1998 Early Bird Contest How long will it take robins to reach the end of the road? Once again this spring, students at Sand Lake School in Anchorage, Alaska will officiate our annual Early Bird Contest. In this contest, we challenge you to predict when the first robins will be seen in Anchorage. To enter the contest, simply answer this question:
(To respond to this Challenge Question please
follow the instructions at the end of this report.) Discussion of Challenge Question #7 Last week we asked Challenge Question #7: "Why do you think male robins return before the females? What are the advantages and disadvantages of coming early?" Laura Erickson reminded us of some of the risks of early migration above. Here are thoughts from students: "The early bird gets the worm--and the best territory!" say students at Crested Butte Community School. "We think male robins come first because they need to find the biggest tree or best place for a nest. Then they won't have to fight off other males when the female arrives or search very far for things to build a nest with. Also the male with the best place for a nest will get the best (or the most?) females to mate with."
Although not found in the scientific literature, this answer is good for making you smile: "The male returns
first so when the female arrives he will cheer her up by singing and cheering," offered Terese and Aaron in
Ridgewood, NJ. (slang@ridgewood.ridgewood.k12.nj.us) 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 The Next Robin Migration Update Will be Posted on April 6, 1998. Copyright 1998 Journey North. All Rights Reserved. |