Enter The World of the Monarch Butterfly

Why the Monarch?

Image Credit: Chris Frost/

The monarch butterfly, Danaus plexippus, is perhaps the most well-known and beloved butterfly in the world. A favorite topic in classrooms throughout North America, it may also be the most well-studied butterfly in the world, the focus of many thousands of scholarly articles. Native to North and South America, monarchs can now be found as far afield as New Zealand with populations expanding their terrain in search of  warm areas where milkweed grows, the essential food source for monarch larvae. Relatively large (for a butterfly) and beautifully marked, each year millions of monarchs from the central and eastern US fly thousands of miles to reach their wintering sites in central Mexico. 

Most monarchs live relatively brief lives, around 4-5 weeks, but these migratory generations must live long enough to survive their arduous journeys to Mexico with enough stored energy to outlast the winter and begin the migration back to the US the following spring—a return journey that will only be completed by their progeny. 

The species currently faces a severe decline in numbers. Populations in the western US may already have fallen below extinction-level thresholds, having decreased by 99% over the past few decades. Populations in the central and eastern US are not faring much better, with decreases of 70%, putting the annual migration itself under increased risk. 

There are many reasons for this decline, including habitat destruction, pesticide use, and, of course, the warming temperatures and increased frequency of extreme weather brought on by climate change. A petition to list the species as officially “threatened” under the Endangered Species Act stalled-out in December, with the US Fish and Wildlife Service stating in a press release that while “adding the monarch to the list of threatened and endangered species is warranted” it is “precluded by work on higher-priority listing actions.” 

Saving the monarch means rebuilding its natural habitat and halting climate change. Both are hard problems to solve. But climate change, in particular, is a notoriously difficult challenge to address as people have a hard time rallying around gradual, somewhat nebulous issues that often don’t seem to impact them directly. The fact that climate change has become so politicized in the US makes the problem even more challenging. I hope The Monarchy will help inform the public about these issues and inspire them to do what they can to support monarch populations and build healthy, natural habitats in their own communities.


Special thanks to:


Dr. Anurag Agrawal, Cornell University

Dr. Adriana Briscoe, UC Irvine

Katie-Lyn Bunney, Monarch Joint Venture

Wendy Caldwell, Monarch Joint Venture

Dr. Chip Taylor, University of Kansas

Dr. Karen Oberhauser, University of Wisconsin-Madison

Dr. Stanley Heinze, Lund University

Dr. Jayne Yack, Carleton University

Maine Audubon

Journey North

Monarch Joint Venture

Monarch Watch

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