American Robin Migration Update: February 16, 1999 American Robin Sightings Today's Report Includes: American Robin Winter Sightings Data About the Robin Map Numbers, Numbers, Numbers Challenge Question # 2 First Robin of Spring? Discussion of Challenge Question # 1 How to Respond to Challenge Question # 2 About the Robin Map What an amazing winter map! We at Journey North are used to hearing about robins wintering in northern places, because every year a few hardy robins do spend the coldest season in the north. But this year is unprecedented in the number of robins that stayed in the northern states and southeastern provinces. Numbers, Numbers, Numbers The map shows the distribution of robins this winter, but can't tell the whole story about how MANY robins were seen in each spot. Some of those little triangles represent a LOT of robins. A few record-breaking robin totals on Christmas Bird Counts: 935 robins in Kansas City, Missouri, reported by Don Armey over 1200 in Berrian Springs. Michigan, reported by Kip Miller 1467 in Toronto, Ontario, reported by Frank Pinilla Many people counted robins even after Christmas Bird Counts were over. Al Ports counted a flock of 1,000 in New Hampshire, and Tom Pirro counted 5500 in one roosting area in Massachusetts. Gerry Rising found perhaps 2,000 near Youngstown, New York. A friend of Carolyn Hall counted approximately 10,000 robins as they exited a grove of trees in north-central Nebraska, and more than 10,000 were counted in Washington State during an Audubon field trip to the Columbia Basin. Which brings us to this week's Challenge Question # 2 Think of at least three different methods people might use to count a huge group of birds like these robin flocks. Which would be the most accurate method? Why do you think scientific papers require a careful description of the method used when the paper is about a bird census? First Robin of Spring? Report OTHER robin behaviors you notice to Journey North! Report the first Robin you HEAR singing this spring to Journey North! This year it's going to be VERY tricky trying to figure out which are the last robins of winter and which are the first robins of spring. Please report the first SINGING robin you hear, and any other new observations, such as the first time you see a robin pulling a worm out of the soil, the first time you see a robin running on a lawn, the first group of three or more robins running on lawns, the first robin carrying nesting materials. Discussion of Challenge Question # 1 What factors contributed to so many robins overwintering this year? As so many students noted, temperatures this fall and winter were, on the whole, very mild, which probably made a lot of robins risk staying farther north. Bobby Pogoloff's 2-3 graders are very clever sleuths. They considered a LOT of possible causes. First they noticed that a lot of the northern robins stayed near the Great Lakes, and pointed out that "maybe the Great Lakes made it warmer because of all the water and the robins stayed in places close to lakes." They also considered the possibility that "first they waited too long because it was warm and then the days got too short to migrate. Or maybe the summer was wet and more food grew so they had enough for the winter." Mrs. Cavanaugh's third graders think "the robins were more affected by the warmer temperatures and the food available to them than the amount of sunlight each day when migration time came." Mrs. Howley's fifth grades in Maine pointed out that "we don't have snow, only rain and that thaws the ground so robins can get worms or other food." A few classes mentioned global warming. Some birders told Journey North that in some western areas apples were left on trees because prices were too low to make it worthwhile picking them to sell, making even more food available for robins. Even scientists are debating about the most important reasons so many robins overwintered, and there is no single right reason. All these factors probably came into play. One other reason that might be important is related to how much food was available during the long mild growing season of 1998. Robins begin nesting as soon as they arrive on their breeding grounds, and nest two or three times before they migrate south again. And when they're eating well, they produce more eggs per clutch. They arrived early in the spring of '98, and left late in the fall. Perhaps with all the food and mild conditions, they nested successfully three or even four times, producing LOTS of babies. So maybe the reason there were so many robins up north AND so many robins down south is that there are simply a LOT of robins right now! How to Respond to Today's Challenge Question 1. Address an e-mail message to: jn-challenge-robin@learner.org 2. In the Subject Line of your message write: Challenge Question # 2 3. In the body of your message, answer the question The Next Robin Migration Update Will be Posted on March 2, 1999 Copyright 1999 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form