The Energy Costs of Flight
How Much Fuel Do Monarchs Burn?

A monarch with a full tank can carry 140 mg of fuel. When it flies without flapping it can travel 1,060 hours on that single tank of fuel.

In contrast, when a monarch flaps its wings it burns its fuel quickly. When it flies its fastest a monarch flaps up to 12 times every second! This fast flight is called “escape flight.” A monarch burns 12.7 mg of fuel every hour during escape flight.

Try this monarch math. You’ll see why soaring, gliding and riding with the wind are so important to migrating monarchs:

  • For how many hours can a monarch butterfly fly before it runs out of fuel?
  • Assume:
    • the butterfly starts with 140 mg of fuel
    • the butterfly is flying its fastest, using escape flight.

Try the math yourself. Then check our answer. >>


* Based on research by Dr.David Gibo >>

"Butterflies get to travel all the way to Mexico and don't even have to pay $4.00 a gallon for fuel!"

2nd grade student, Muncie, Indiana.