The world famous migration

---

Monarch butterfly, member of the milkweed butterfly group known for its large size, its orange and black wings, and its long annual migrations. Monarchs are found primarily in North, Central, and South America but also occur intermittently in other parts of the world. Several subspecies are recognized. 

The annual migration of the Eastern monarch butterfly is one of the most impressive there is. Flying up to 2,500 miles from the US and Canada where they breed, all the way down to the forests in central Mexico where they hibernate, the monarch's migratory pattern is the most highly evolved of any known species of their kind. 

 The eastern population of North America’s monarchs overwinters in the same 11 to 12 mountain areas in the States of Mexico and Michoacan from October to late March. 

 As warm temperatures and lengthening days arrive, they become reproductive, breed and lay the eggs of the new generation. 

Flying South

Eastern North American monarchs fly south using several flyways then merge into a single flyway in Central Texas. It is truly amazing that these monarchs know the way to the overwintering sites even though this migrating generation has never before been to Mexico! 

Meeting sites

Monarchs only travel during the day and need to find a roost at night. Monarchs gather close together during the cool autumn evenings. Roost sites are important to the monarch migration. Many of these locations are used year after year. Often pine, fir and cedar trees are chosen for roosting. These trees have thick canopies that moderate the temperature and humidity at the roost site. In the mornings, monarchs bask in the sunlight to warm themselves. 

Flying North

This starts the northern journey back to North America. Unlike the generation before them, who made a one-generation journey south, successive generations make the journey north. 

Generation 1 monarchs are the offspring of the monarchs who overwintered in Mexico. Each successive generation travels farther north. It will take 3-4 generations to reach the northern United States and Canada. 

Migration tracking 

The northern migration is tracked by an organization called Journey North. You can help track the migration of the monarch butterfly by visiting this site.

Report your sightings!

The Western Monarch Milkweed Mapper project is part of a collaborative effort to map and better understand monarch butterflies and their host plants across the Western U.S. Data compiled through this project will improve our understanding of the distribution and phenology of monarchs and milkweeds, identify important breeding areas, and help us better understand monarch conservation needs.

Help us track monarchs and milkweed across the West!

To track the southern migration at Papalotzin, The Journey of the Monarch Butterfly.

For milk weed on the east coast, while we have no awesome tracker, you can see on monarchwatch.org what milkweed is best suited for your area.

MILK WEED MAP by state and country

Migration East

Millions of monarchs east of the Rocky Mountains make their 3,000 mile migration from Canada to Mexico every year. This sanctuary was discovered  in 1975 by Frederick Urquhart, a zoologist. Fred and his wife, Norah Roden Urquhart, along with co-workers Catalina Trails and Ken Brugger, discovered where the butterflies spend their hidden overwintering months in Mexico. Yearly the Monarchs make their way to their destination. As magical as it is, the decimation of the population has raised the idea that this may not happen every year..forever. It is with our help that we will see them for years on end.

Migration West

Monarchs over-wintering in The Butterfly Grove at Pismo Beach  as well as The Monarch Grove Sanctuary in Pacific Grove, California celebrates this over-wintering event from October through February. Recent years have been much different than most. The attendance has dwindled. At times there were butterfly no shows. Very disheartening when Monarchs used to arrive in droves. Hopefully the populations increase in the coming years and us humans can get back to visiting one of the wonders of the world.