Monarch Butterfly Update: June 20, 2012
Please Report
Your Sightings!
Report Your Sightings
Thank you, citizen scientists, for helping to track the monarch's spring migration! Summer is here, the migration is complete, and the breeding season is underway. How many generations will the monarchs produce—and which generation will migrate to Mexico?

This Week's Update Includes:

Image of the Week
Monarch Butterfly Caterpillar
How many generations?
News: Astonishing Observations in Alberta
What a Year!
Spring migration 2012 has been a record-breaking season and it's going out with a bang. During the past few weeks, monarchs have appeared in unprecedented numbers, early, and in places where they're rarely seen.

Look at the rash of sightings in Alberta on the migration map. According to observers, strong southeast winds led to an outbreak of butterflies there beginning June 7th. Very early!

One insect expert said he had never before seen a monarch in Alberta in his 36 years of living there.

A University of Alberta faculty member said of the sightings north of Edmonton, "This might be the farthest-north record for a monarch for a long time (at least since I saw one in about 1977)."

An astonishing gathering of nectaring monarchs was captured in a single photo in Ontario on May 25th. Four in one shot! In 19 years of tracking spring migration, we've never seen an image with more than one nectaring monarch—yet another sign of an unsually large population this spring.

Thank You Citizen Scientists!
As the monarchs reach the end of the migration trail we thank the people who made tracking it possible—you! The observations you have contributed are now part of the historical record. Over time, these data reveal how monarchs respond to changing weather, climate and the seasons. This work is impossible without your help. Thank you!

Fall Migration Only Two Months Away
The first monarchs will have begun their journey south by mid-August. We hope you'll return to report your fall observations. We'll post the first Fall Migration Update on August 30, 2012. Meanwhile, carpe diem!

Monarch butterfly in Alberta
Photo: Robert Hughes
Early in Alberta
Monarch butterflies on blooming lilacs
Photo: Vern Hibbard
Four in One!


Report Your First

No matter when you see your first monarch of 2012, we want to know about it.


It's the Breeding Season: How Many Generations?
A New Generation Each Month!
This annual cycle graphic shows when and where each generation of monarchs is produced during the breeding season. During the summer in the north, monarchs can produce a new generation in about 30 days. This typically results in three generations. The monarchs that migrate to Mexico this fall will be the great-great-grandchildren of those who left Mexico this spring.

An Extra Generation?
By arriving early this spring, monarchs may be able to squeeze in an extra generation in some places. An extra generation is possible where monarchs arrived early and/or where temperatures are unusually warm.

Monarch Butterfly Annual Cycle Graphic

Count the Generations

The Migration: Maps and Journal Page
Thank you for helping to track the monarch's spring migration. If you haven't seen your first monarch of the season yet, please report it whenever you do.

Monarch Butterfly Winter Sightings Map of milkweed emergence: Spring 2011 Worksheet: Journal Page
First Monarch
(map | animation | sightings)
First Milkweed
(map | animation | sightings)
The first FALL migration update will be posted on August 30, 2012.