How To Save The Monarch Butterfly

Monarch numbers are rising but can they fully recover?

Monarch butterfly
Monarch butterfly numbers are dwindling, despite strong efforts at protection. Sarah Orsag/Getty Images

Here's the good news: Monarch butterfly numbers are on the rise.

The bad news? Experts say that the overall, the species is still on the decline, despite strong efforts at conservation.


Monarch Butterflies: Some Background

First, a little background. The monarch butterfly is probably the most recognizable butterfly species in North America. And its primary claim to fame is the amazing migration it makes every year from its breeding grounds to its wintering grounds.

In Eastern North America, these beautiful orange and black butterflies spread across the United States and Canada in the warmer months, but travel 3,000 miles south to survive the colder winders. Every year, generations of monarch butterflies make this epic journey up and down the North American continent.

This monarch butterfly's migration has been described as one of the world's most amazing natural phenomenon. But a few years ago, ecologists noticed that there were fewer and fewer monarchs making the migration journey each year.


Monarch Numbers Are Rising, But Is It Enough?

So it is good news that the monarch numbers are starting to bounce back. In Mexico, the monarchs primary wintering ground, conservation efforts have led to a population increase of 255 percent. Due to their small size, ecologists count their numbers in acres covered rather than trying to count individual butterflies.

In the winter of 2015-1026, monarch butterflies covered 10 acres, a dramatic increase over the 2.8 acres covered just the winter before. While these numbers are an improvement from the record low of 1.6 acres in 2013-2014, they are still far less than the population peak of 44.5 acres noted in the winter of 1996-1997.

So while ecologists are happy with the population increase, they know that the species still has a long way to go before it is out of danger. And many experts think that current protection levels are not enough to support a full recovery.


Threats to Monarch Butterfly Numbers

Monarch butterflies face a number of threats. In Mexico, their wintering habitat has declined thanks to illegal logging. In North America, the monarch butterflies primary food source - the milkweed - has been on the decline.

Like all butterfly species, the diet of the monarch changes as it develops. In the caterpillar stage, monarchs live exclusively on milkweed plants. Milkweeds are wildflowers in the genus Asclepias. Adult monarchs consume nectar from a wide range of flowers, including milkweeds. Monarch butterflies also lay their eggs on milkweed, seeking out the plants in meadows, parks, and fields.

It goes without saying that the milkweed plant is critical to the survival of the monarch butterfly.


Monarch Conservation Programs

Conservation programs over the last few years have focused on protecting the land where monarch butterflies winter in Mexico and protecting milkweed in the U.S. and Canada. In Mexico, efforts to support local communities through business opportunities and provide greater security to conservation areas has reduced the threat of illegal logging on forests.

In the U.S., a multimillion dollar project has supported efforts to replant milkweed and nectar-producing crops along field borders and pastures. 


But many who study the monarch butterfly think that these efforts may not be enough to counteract the bigger threat to the species - the use of the pesticide glyphosate which has destroyed much of the monarch's milkweed supply throughout the U.S.

Records show that milkweed habitats have been decreasing since 1996 which just happens to coincide with the introduction of genetically-modified crops that were engineered to tolerate the herbicide glyphosate.

Since 1996, studies have documented a dramatic decrease in milkweed numbers, particularly in agricultural areas, resulting in a loss of milkweed density of around 50 percent from 1999 to 2009. As glyphosate use continued to increase, milkweed numbers continued to decline - and with it, so did the monarch butterfly population.


How To Protect the Monarch Butterfly

So what can you do to protect monarch butterflies? 

  1. Protect America's grasslands. These lands contain more than just grasses. They are also home to milkweed, the monarch butterflies primary food source.
  2. Plant milkweed. If you have room in your backyard or garden, why not plant some milkweed? Every little bit helps provide food, shelter, and breeding grounds to support monarch butterflies.
  3. Pass on pesticides. Pesticides that kill milkweed destroy the food that monarch butterflies need to survive. Don't use them in your own backyard and support efforts in your community to use non-chemical methods in local landscaping.