Spring Fever Testing a Temperature Theory About Robin Migration Time: 1 period + occasional time over several weeks Standards Background An age-old theory about robin migration says that robins arrive in an area when the average temperature is 36 degree F. Is it accurate? Why not test the theory yourselves? Preparation To test whether robins seem to travel with average temperatures of 36 degrees, first find out when robins generally return to your region each spring. Begin the study about a month before their average arrival date. Exploration Average Temperatures (last week) Click on this map to see a larger one. The lines and colored bands show places that had the same average temperatures last week. These will migrate across the continent as temperatures warm in the spring. (Look at or print a new map each week!) * Can you find the approximate location of your hometown? What was its average temperature last week? * How did that compare with your temperature records? If they varied, explain why you think they did. * Name 2 states that could have had 36 degree F average temperatures. * Name 3 states you think were too cold for robins. Explain why. (Definition: The lines that connect places with the same average temperatures are called isotherms.) Calculate your average weekly temperature. Think about how you could find that — or simply use Our Average Weekly Temperatures data sheet. Each week, ask yourselves, "Have we seen any robins yet?" Continue to calculate your average weekly temperature and keep your eyes peeled! When your robins show up, how will you answer these questions? Did the robins show up . . . a) before your average weekly temperature reached 36 degrees F? b) right around that time? c) once the average temperature was above 36 degrees? Making Connections — Journaling and Discussion Questions Does the isotherm theory seem to hold true where you live? Why or why not? Which of robins' basic needs could be affected by temperature, and how? > What other factors might influence the date of the robins' arrival? Do you see a connection between the arrival of robins and the appearance of earthworms? What do you think causes earthworms to appear? Digging Deeper Remember to report the FIRST migrating robin you see this spring. Look at an average weekly temperature map and figure out about where the 36 degree F average temperature line appears. Next, look at a map of Journey North's reported robin sightings for the same week. Do you notice any correlations? Watch for the first earthworms and note your average weekly temperatures when worms appear. When you see the first earthworm of the season, report it to Journey North! Choose a faraway Journey North school and see if you can predict the arrival of the first robins and earthworms in their location. You can find the daily high and low temperatures of most cities via these links or in the newspaper. You can also exchange temperature data online with another class. Why follow the 36 degree average temperature line (isotherm)? Scientists believe that by migrating north just behind the advance of this isotherm, migrating birds will find food and open water available. It also allows them to have as long a breeding season as that climate will allow. This Season Teachers Kids Orientation Registration Search Copyright 1997-2008 Journey North. All Rights Reserved. Questions or comments? Contact us.