Monarch Migration

When fall arrives, look to the skies—the monarch butterflies are taking flight. Learn about monarchs, why migration occurs, reasons to protect this priority species, and how to make your backyard better for them. 

Why do monarchs migrate?

Monarchs are unable to survive cold temperatures in northern climates, so in fall, they migrate south to overwintering locations to roost (or rest!). The monarchs in Mexico roost in oyamel fir trees, while monarchs in California roost in eucalyptus, Monterey pines, and Monterey cypresses. Regardless of location, the butterflies will roost in massive clusters, sometimes with thousands upon thousands of butterflies located on a single tree. 

 

Sunday Fun Fact: Not all monarchs migrate! There are populations of monarch butterflies in Florida able to survive throughout the year without the need to migrate to warmer climates. 

What does monarch migration look like?

 

When do monarchs migrate?
Similar to
birds, monarchs complete a two-way migration (north and south). Fall migration season for monarchs occurs from September through early November and begins when temperatures start to cool in their summer regions. Monarchs are only on the move during daylight hours.

How do monarchs migrate?
How monarchs navigate is still not entirely known, but might be related to magnetic pull or the direction of the sun. What we do know is monarchs use a combination of air currents and air thermals (columns of warm rising air) to travel up to 3,000 miles to overwintering grounds. 

Where do monarchs migrate?
Migration pathways stem from across the US and Canada and lead into warm coastal areas of California, Baja California, central Mexico, and southern Mexico. Monarchs east of the Mississippi head to Mexico, while western monarchs overwinter in California.

How to build a stop-over habitat for monarchs

Monarch migration is one of the longest-standing migrations in North America. Additionally, monarchs help pollinate ecosystems, bring attention to critical habitat conservation needs, and help bring attention to pollinator protection actions we can all adopt in our sustainability journey.

Plant milkweed.
Milkweed (Asclepias spp.) is the host plant for monarchs. We can’t emphasize enough that this is the only plant monarch butterflies can lay their eggs on and the only plant monarch caterpillars can consume. In short, it’s 100% essential to every phase of the monarch lifecycle. Find the best milkweed species for your yard hereSunday Tip: There are milkweed lookalikes that are poisonous to monarchs and other wildlife, so beware of swallow-worts!

Install a pocket prairie. Nectar sources are the second most important habitat component for monarchs. While milkweed is vital for monarch caterpillars, adult butterflies can’t survive off of milkweed alone, so make sure to plant a variety of valuable flowering native plants to provide nectar for adult monarch butterflies.  

Provide water and heat sources. Cold-blooded monarchs need places to warm themselves and stop for a drink during their migratory journeys. Strategically placed rocks and areas where water can collect will help our winged-friends thrive.

Think before managing your yard. Monarchs already have enough obstacles in their way when migrating to and from overwintering locations. When you care for monarchs, you’re also doing better for your family, pets, and the planet as a whole. 

  • Avoid planting invasive species that overtake native habitats.
  • Use pesticides only as a last resort; if needed, use them responsibly, sparingly, and according to label instructions. 
  • Never spray flowering plants with chemicals that harm pollinators. 

Help monarchs find their way

Support monarch conservation through learning, volunteering, advocacy, and more. Anyone can be a pollinator advocate—and it can be as easy as keeping up to date with the latest pollinator news, or as involved as becoming a community scientist!  

  1. Follow Sunday’s 1% for the Planet partners: Xerces Society, People & Pollinator Action Network, and Audubon Rockies
  2. Join Monarch Watch — a cooperative network of students, teachers, and researchers dedicated to the study of the Monarch
  3. Register your native garden with the Monarch Waystation to support monarch conservation.
  4. Get involved with the Monarch Joint Venture program to take part in community science efforts and learn how you can support pollinators in your community.  

CITED SOURCES

Monarch Butterfly. Texas A&M Extension.  

Monarch Butterfly Fact Sheet. University of Maine Extension.

Monarch Butterflies. Cornell Cooperative Extension. 

Monarch butterflies facing a crisis. University of Illinois Extension.

Fall-Migrating Monarchs. Penn State Extension.  

viceroy butterfly – Limenitis archippus (Cramer). University of Florida Extension. 

Monarch Butterflies Bring Together Conservation and Culture. The Nature Conservancy. 

Monarch Butterfly (Danaus plexippus). U.S. Forest Service.   

Monarch Butterfly Conservation in North America. U.S. Forest Service.