Bald Eagle Migration Update: April 23, 2002 Today's Report Includes: Migration Map and Data Only This Week's Migration Highlights Reminder: Peter Nye?s Work Featured on PBS This Week Migration Map and Data Only Just a quick update today to give you the latest data for your migration map. Watch for a full update next week, according to the schedule above. Link to Latest Data: Eagle #E47 Eagle #E49 Eagle #E50 Eagle #E63 Eagle #K58 Eagle #K70 Eagle #K72 Golden Eagle #A20 Printer-friendly Version This Week's Migration Highlights Golden Eagle A20 is heading north at last! The satellite caught him during migration on April 15th. Click on the map and you'll see four readings from him that day. Exactly how far did he traveled between 1:30 and 7:06 pm? In the past, those of Peter Nye's birds that leave LATE in the season go the LONGEST distance north. Where do you suppose A20 will go? Predict where he'll be at this time next week. You'll notice that Eagle E50 didn't "beeline" across the Gulf of St. Lawrence. This is really no surprise because eagles rarely migrate over large bodies of open water. Here's why: Eagles get a free ride by flying on "thermals." Have you ever looked close up at a car on a hot, sunny day and seen the air wiggle? That heated air is rising, floating above the cooler air farther from the car, making the cooler air take its place, only to get heated by the car and rise. All this rising air is called a thermal, and though we can't really feel it, eagles with their enormous but feather-light wings and hollow bones can actually float on a thermal, making their migration very easy. Fortunately, eagles don't need a hot car to find a thermal. Thermals form anywhere where the air in one spot is just a couple of degrees warmer than the air next to it. So there are thermals above highways, and next to rivers and lakes, where the ground is warmer than the water. But there are never thermals over a big lake, so eagles must travel along the shore. Reminder: Peter Nye?s Work Featured on PBS This Week Just a reminder to watch the PBS/Bill Moyers special on the Hudson River on the 23rd and 24th of April. You'll see Peter Nye in action. The Next Bald Eagle Migration Update Will Be Posted on April 30, 2002 Copyright 2002 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form