Making Sense of Robin Migration Maps
A Map-Reading Tutorial: Part 2

Look at this map, showing six additional weeks of data.
How can you make sense of all those dots?

First, look at the sightings that are farthest south for each date.

1. To do this, hold your string against the bottom of your computer screen when you have these words and at least the bottom half of the map showing.

2. Slowly move the string up the screen until you come to the first triangle, or the first dot of each color. Notice where it is. (This would be an even more accurate method if your string were curved the same as the latitude lines.)

• Which state has the most southern wintering report (the first triangle)?
• Where do you find the first red dot? How about the first pink dot? The first blue dot? These bottom dots show the southern range of "first sightings." What direction does the migration seem to be moving (e.g., north or south)?

Next, look at the sightings that are farthest north for each date.

Read these instructions first, and then scroll to see the top half of the map on your screen. Hold your string on the top of the screen and move down, looking for the first triangle, and the first red, pink, and blue dot as you move the string down. After you do this, come back here and read on.

• Did you see the same clear progression as you saw when you moved your string up from the bottom? Probably not. Here's why:
The very first robins to move are the ones most sensitive to weather, daylength, and other signs of spring; some robins are also more restless than others. The birds at either extreme don't always follow the "rules"!

Finally, try to see the clusters of color.

Find the latitude at which:

* half the red dots are above it and half below it.
* half the pink dots are above it and half below it.
* half the blue dots are above it and half below it.

• Is the biggest cluster of pink dots a bit north or south of the biggest cluster of red dots? Where is the cluster of blue dots in relation to the others?
• What does this tell you about the general (average) progression of the migration?
 You Are the Scientists! By trying to make sense of the dots (data) on this map, you are thinking like scientists. You are able to "eyeball" the dots and look for patterns. Scientists might use different types of graphs and math equations to more precisely analyze what the data points reveal about the progression of migration.

Part 3: Final Migration Map for the Year