Temperature and Migration in our Hometown
Slideshow Overview

Monarch butterflies are in a race against time during fall migration. They must leave the north before they're trapped by the cold. If a monarch's thoracic (body) temperature is below 55° F (13° C), it cannot fly. Use these activity ideas to explore how your hometown temperatures affect monarchs during fall migration.

Observe: Watch How Temperatures Fall...in the Fall!

Take a look at this map to observe how quickly temperatures change week-by-week in the fall. With each passing day, monarchs have a smaller and smaller window of time in which they can fly.

Select a location on the map and have students predict when it will be too cold for monarch flight.

Explore: Temperature and Migration in Your Hometown

1. Predict: How many hours could monarchs fly in your hometown today? Remember, migrating monarchs do not travel at night and they cannot fly if they are too cold.

2. Measure daylight hours: Calculate today's day length using sunrise/sunset data. What time in the morning could the monarchs lift off? Remember: Monarchs can raise their temperatures above air temperature by basking in the sun and/or shivering. What were the sky conditions: sunny or cloudy? Do you think the butterflies were able to bask in the sun to warm up their flight muscles? What time in the evening must the butterflies come down to rest? How many hours do you predict monarchs could fly between sunrise and sunset?

3. Measure outside temperatures periodically during the school day. How many hours could a monarch fly today? How will the sunny or cloudy conditions affect temperatures and monarchs? As a general rule, monarchs need air temperatures of at least 50°F on a sunny day (or 60°F on a cloudy day).

4. Analyze! Between sunrise and sunset, how many hours could monarchs have flown? How many hours was it too cold to fly? How did these results compare to your predictions?

5. Continue gathering data as the season continues. Each day, check the previous day's temperatures. Go to weather.com. Put in your zip code. Choose "yesterday" from the menu and then choose "hourly reports." (You'll find times and temperatures in the lefthand columns.) Make a graph that shows how many hours in each 24-hour day the temperature is above (or below) 55 degrees Fahrenheit.

6. Predict where in the country monarchs will be able to fly today or this week using this interactive map.

National Science Education Standards