Monarch Migration News: Nov. 3, 2011
Please Report
Your Sightings!

"The monarchs are truly arriving now," exclaimed Estela on Friday from Angangueo. Why do monarchs fly across the continent to reach this part of Mexico? What's so special about this place?

This Week's Update Includes:

Image of the Week

Monitoring monarch butterflies arrival at overwintering sites in Mexico.

Off the Chart!

News: Arriving En Masse!

"Monarchs adorn the sky while people in town prepare one of our most significant festivities in all México," Estela Romero wrote this week. "The ancestral belief for us that Monarchs are the souls of our dead relatives who arrive on this date to visit us, expressing with it the deep spirituality and festivity of Mexican people."

Dia de los Muertos in Angangueo, Michoacan, Mexico

Students display artistic and original ofrendas.

Warm October: More on the Way

NOAA reports unsually warm October temperatures around the globe. Did unseasonable temperatures extended the migration in the monarch region? People reported monarchs from over 80 places during the past week, including the northernmost report from Toronto, Ontario. Observations from students at Ann Arbor Open School in Michigan show monarchs are still coming down from the north.

In Texas, a steady stream is passing through. As Cold Front Number 9 swept southward last week, monarchs moved swiftly toward their winter home. A substantial flow of 10,000+ monarchs was reported from the Texas Gulf Coast on Saturday.

Warm October

California School Reports: Monarchs Arriving Too!

On the West Coast, monarchs are arriving now at their traditional wintering sites along the California coast. From Pacific Elementary in Santa Cruz, 3rd grade teacher Julie Notle sent pictures and news:

"We have observed many monarchs flying over our schoolyard. As of this evening, there are hundreds fluttering around the eucalyptus trees of Lighthouse Field in Santa Cruz, about 100 yards from the ocean.

Explore this distribution map to learn more about North America's two monarch populations. Although there is an unknown degree of overlap, monarchs in the eastern population fly to Mexico for the winter. Monarchs in the western population fly to the California coast.

Over-wintering monarchs on the California coast.

Over-wintering on the California Coast.


Slideshow: Why is this place so special for monarchs?

Hundreds of millions of monarchs are migrating to Mexico to spend the winter in an astonishingly small region. The butterflies will gather on a dozen mountaintops in a region only 73 miles wide. What conditions make the habitat in this region ideal for monarch survival? In this week's slideshow, find out what scientists are learning about the unique microclimate of the monarch overwintering region.

Slideshow: Why is this place so special for monarch butterflies?Slideshow

The Migration: Maps and Journal Page
Monarch Butterfly Migration Map: All Sightings, Fall 2011 Monarch Butterfly Migration Map: Fall Roosts, Fall 2011 Journal

All Sightings

(map | sightings)

Fall Roosts

(map | sightings | archives)

Seeing Monarchs? Please let us know!

The FINAL Monarch Migration Update will be posted November 10, 2011.