Comparing Maps
Robins, Rainfall, and Human Populations

• Last week, you looked at maps that compared U.S. winter robin sightings with the location of the human populations. (Roll over the map below to see the comparison.)
• It looked like there were more robins in areas with more people. But we questioned that conclusion. There might just be more eyeballs searching for and reporting robins!
• We wondered, What else could affect where spring robins are reported?
  Let's explore! >>