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You Know You Want To Help (6-Legged) Monarchs. Here’s How.

Last year, a hard year by monarch butterfly migration standards, 60 million monarchs showed up at their misty wintering grounds in Mexico. This year, so far, a mere 3 million have straggled in — and late, too, according to a disturbing must-read piece (“The Year the Monarch Didn’t Appear”) published last Friday in the New [...]

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


A gorgeous monarch butterfly caterpillar on an equally gorgeous native American milkweed, Asclepias tuberosa. Photo by Marshal Hedin; used with written permission. Click image for source.

Last year, a hard year by monarch butterfly migration standards, 60 million monarchs showed up at their misty wintering grounds in Mexico. This year, so far, a mere 3 million have straggled in -- and late, too, according to a disturbing must-read piece ("The Year the Monarch Didn't Appear") published last Friday in the New York Times Magazine.

The reasons are straightforward: we've converted most of monarchs' habitat to crops, pasture, and lawns. Where we grow crops, we now often spray herbicides that kill everything but the particular plant we want. Where we grow gardens, we plant grass or showy but often nutritionally bankrupt species, at least from an insect perspective. And we aren't planting enough milkweed to make up for the resulting losses. Monarch caterpillars must eat milkweed, a somewhat dowdy plant that many gardeners ignore.


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But, to believe a new study in Conservation Letters led by scientists at the U.S. Geological Survey, lots of Americans who aren't helping already seem willing to do something about this problem, to the tune of hundreds of millions of dollars. The study's authors analyzed a survey commissioned by the National Gardening Association, run by Harris Interactive, and mailed to a random sample of all U.S. households. 2,290 responded.

Black dots indicate locations of this survey's respondents. Blue arrows indicate migrations. Two overwintering grounds are shown: one in California and one in Mexico. From Diffendorfer et al., 2013. Click for source.

The scientists asked, “What is the one-time amount you would spend, or have spent, to grow flowering nectar plants or milkweed that benefit monarchs at your home?” Based on the responses, the scientists estimated American households who are not already growing butterfly-friendly plants would be willing to spend a total of $933 million for nectar-bearing plants and a total $473 million for milkweed. The survey also asked about pure interest in growing butterfly-friendly plants. Some 16 percent of the respondents who don't already grow nectar plants said they "would" grow nectar plants in the future, while 20 percent said the same about milkweed. But of course, even the best intentions can go by the wayside when life intervenes.

So what's holding you back, assuming you have access to a place to plant and sufficient interest? Is it just the final step -- connecting the People Who Want to Help with the People Who Have the Stuff They Need to Do It? Allow me to help.

Finding native milkweed plants or seeds can be a challenge at garden centers focused on growing what sells. They may also offer species that aren't the best adapted to your particular growing conditions. Search out nurseries in your area that focus on selling native plants to increase your chance of getting well-adapted milkweeds.

But there's an important question you should ask before you purchase. According to the Conservation Letters study, it has apparently become standard practice at many nurseries to spike the potting soil with broad-spectrum insecticides like neonicotinoids -- related to the plant-made insecticide nicotine (yes, that nicotine), but that's another story -- that permeate leaves and nectar. The resulting plants may please gardeners who purchased the plants by bearing leaves that don't get munched and ragged, but also kill many beneficial native insects, including caterpillars and adults of moths and butterflies. So if you do buy a milkweed or nectar plant, it's worth asking your nursery or garden center about their potting soil practice.

Growing your own plants from seed may guarantee pesticide-free plants but unfortunately may not be as straightforward as sprinkling seeds in the ground. I received a catalog in the mail last month from a company called "Native American Seed" with a description for a clever product designed to help you carry out your good intentions to help monarchs -- a "Sustain the Migration Kit" -- that implied as much, but also offered to help.

Have you struggled to get milkweed seeds to sprout? Do you think your green thumb just isn't so green? Would you like to help the Monarch Butterfly by providing Native Milkweeds but think they just aren't available in the marketplace? Do you have a little room in your refrigerator? Do you have a little room in your flower bed? Are you willing to make a move? If so, let's get going. With our Sustain the Migration you will be a hero to all those hungry Monarchs.

This is but one example -- and I know nothing of this company and cannot endorse it or vouch for it. Caveat Emptor. It also includes species selected for Texas, though they may grow well elsewhere too. There are others -- a quick Google search turns up many, as likely would a trip to your local native-friendly nursery. And again, I am not endorsing and cannot verify the trustworthiness of any of these organizations, but here are a few:

Monarch Watch

The Butterfly Farm

Live Monarch

If you want to plant but milkweed proves too hard to find or grow, consider planting native nectar-bearing butterfly-friendly flowers and flowering shrubs, which like milkweed also benefit a wide variety of pollinators. And if you can't or don't have room to plant, think about your friends and family. Right now is the time of the year that gardeners start dreaming up plots for the spring. Native milkweed seeds could be a great gift to people who love growing things -- or to kids. And if none of this sounds good, you could always contribute to monarch conservation organizations, of which there are several a quick Google search away.

But really -- how can you resist the chance to run a butterfly conservation experiment in your very own yard or balcony, wherein you might just get to watch for yourself the miracle of metamorphosis, and really feel that you made a difference? Nearly everywhere in the Lower 48 is monarch habitat, as you can see from the map above, so nearly any American (and lots of our friends in Mexico and Canada!) can help.

It is hard for me, as I'm sure it is hard for you, to watch the depressing ending to nearly every d--- natural history documentary. It is easy, so easy, to feel powerless. This is one thing you can do, people. Be a hero to some hungry monarchs.

Reference

Diffendorfer J.E., Loomis J.B., Ries L., Oberhauser K., Lopez-Hoffman L., Semmens D., Semmens B., Butterfield B., Bagstad K. & Goldstein J. & (2013). National valuation of monarch butterflies indicates an untapped potential for incentive-based conservation, Conservation Letters, n/a-n/a. DOI: 10.1111/conl.12065