monarch butterfly migration maps and sightings Monarch Migration and Milkweed Maps Monarch Butterfly Facts Monarch Migration News Monarch Butterfly Home Page Report Your Sightings! Monarch Butterfly Resources Monarch Home Page Journey North Home Kids Monarch Butterfly

How Many Monarchs in Mexico?
Winter Population Estimates

All of the known butterfly colonies in Mexico are measured once each winter. Like a snapshot in time, these annual winter measurements give scientists a chance to estimate the size of the entire overwintering population.

Winter 2006/2007: The butterflies covered 6.67 hectares. (One hectare equals 2.47 acres.)

How will the winter of 2007/2008 compare?

The graph above shows each winter's population estimate since the winter of 1994/1995. Since that time, when was the population the highest? The lowest? How do this year's numbers compare?

What is a monarch colony? Look at the photo to the right. The orange you see in certain trees are monarch butterflies! This is a monarch colony. Find out how scientists measure and estimate monarch numbers.

Learn More!

Butterfly Trees
From above, a monarch colony looks like a golden carpet.

How many football fields would last year's population cover? >>

Education Standards >>

Journey North Home Page   Facebook Pinterest Twitter   Annenberg Media Home Page
Copyright 1997-2017 Journey North. All Rights Reserved.   Contact Us    Search