A couple of weeks ago the International Union for Conservation of Nature declared the monarch butterfly to be an endangered species. Mark Garland, naturalist and former director of the Cape May Monarch Monitoring Project, joins to talk about how monarch migrations have changed over the past few years, what their new designation means for conservation, and how listeners can help the species rebound with butterfly gardens.
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Matt Katz: It's The Brian Lehrer Show on WNYC. Good morning again, everyone. I'm Matt Katz, filling in for Brian who's off today. We're going to end the show today, as Brian often does, with a look at a local slice of nature. You've heard Brian's BLTrees series, but now we'll turn to monarch butterflies, which maybe you've heard were just classified as endangered by the International Union for Conservation of Nature.
That announcement came about two weeks ago, maybe it's confusing to hear that because maybe you've also seen some recent articles about monarch populations coming back from diminished numbers in places like California or Mexico. What's going on here? More importantly, what will it take from policymakers and citizens to help monarch butterflies make a comeback?
We'll talk about butterfly gardens later for all your green thumbs listening, but before we get to that, let's welcome someone to help us take stock of the current situation as it is. Naturalist Mark Garland who's done a lot of work with the New Jersey Audubon Society, and just recently retired from his longtime post as director of the Cape May Monarch Monitoring Project is joining us now. Hey there, Mark. Thanks for coming on WNYC. Thanks for coming back to WNYC.
Mark Garland: Hey, happy to be with you.
Matt Katz: Great. We are a little bit confused here because are monarch butterflies going away? Are they surging in population? This international non-government organization is calling the monarch endangered. Can you explain this, sort this out for us a little bit? What standards are they using to put the monarch on what they call the Red List of endangered species, and how does that jive with monarch butterfly populations doing well elsewhere?
Mark Garland: Well, doing well is a relative term. Monarchs have at least four generations a year and each female can lay more than 200 eggs at a time. Like many insects, their population goes through these wild fluctuations normally. What happens from one year to another is pretty insignificant. What we've got to look at is the long-term data. We've got a couple of studies, one in Mexico, where they overwinter, and one here in Cape May that have been looking at the populations for 30 years.
In that 30 years, you'll see these cycles of up and down, but the trend, especially down in Mexico is a dramatic downswing. Yes, the numbers in the last couple of years have been up a little bit from the absolute low point, but a lot of conservation biologists think we're still below the number needed in Mexico to keep the population going in the event of some environmental crisis that really knocks the population down.
One of the things that's happened four times in the last 20 years is a freak winter storm hitting the mountains of Mexico where the monarchs overwinter and up to an 80% mortality down there. At what point if one of these events which naturally occur periodically, one of these events happens will the population not be able to recover? The IUCN sees that long-term trend, also sees climate patterns changing with climate change where these type of storms hitting the wintering areas in Mexico are occurring more frequently. They see it as a vulnerable population.
Matt Katz: The IUCN being the International Union for Conservation of Nature. It's interesting because that designation, this endangered designation as a dweller of a large metropolitan area when I hear the word endangered, I think of blue whales, orangutans, black rhinos, animals in far-flung habitats, but the IUCN designates it differently when it's part of our lived environment. Is that right? Am I getting that correct?
Mark Garland: Well, I think wherever it happens to be, if a creature is in a vulnerable situation where there's a possibility it could disappear from the earth, whether it's in an urban, suburban, rural, whether it's in North America, in Africa, wherever, this is an international organization supported by something like 1,400 different agencies around the world, coordinated through the United Nations that is really looking at biodiversity and conservation on a global scale. Just because you're in an urban area doesn't mean you don't have wildlife that is of some significance.
Matt Katz: Listeners, we want to hear your monarch butterfly questions. What do you want to know about these beautiful creatures, their migration patterns, or what it means now that they've been classified as endangered, call 212-433-WNYC, 212-433-9692. We'll also take your butterfly garden stories and tips and anything else you want to bring to our conversation with naturalist Mark Garland who until recently was the longtime director of the New Jersey Audubon Society's Cape May Monarch Monitoring Project. 212-433-WNYC, or you can tweet us @BrianLehrer.
This international organization considers monarchs endangered, Mark, but the US government has not classified them that way even though they've been apparently a candidate for government protection since 2020. Why hasn't the government made that leap and made monarchs a protected species?
Mark Garland: Oh, it's a funny, in a sad way, a funny situation. I've actually got the wording from the US Fish and Wildlife Service in front of me, and here's what they say. "In December 2020, after an extensive status assessment of the monarch butterfly, we determined that listing the monarch under the Endangered Species Act is warranted but precluded at this time by higher priority listing actions."
That's a funny way to put it. They see that it's worthy of protection, but once a species is put on the endangered species list by US law, the federal government is required to develop a species recovery plan and that takes a lot of money, a commitment that the Fish and Wildlife Service wasn't prepared to take, partly because of their budget restrictions, and partly because an assessment that other species were, in someone's opinion, of greater concern, of greater vulnerability.
Matt Katz: Can you give a sense of the importance and the role of the monarchs' migrations? How these butterflies interact with local flora and fauna as they make their ways North for the warm months and South again when it gets colder?
Mark Garland: It's a remarkable long-distance, multigenerational migration that covers most of the United States, Southern Canada, and of course, virtually, all of them with a few exceptions are ending up in the mountains of Central Mexico for the winter four or five generations removed from the ones went there a year ago. There's two things they need. The caterpillars have to have some member of the milkweed family. Like many insects, they've got a very, very specific relationship with a certain group of plants. Those are the only things that the caterpillars can eat, are the leaves of milkweed plants.
I like to joke that it's the kids who are the picky eaters. Adult butterflies actually don't eat, they drink. They sip nectar from flowers, and they're not picky. They will feed on the nectar of pretty much any nectar-producing flower, native ones as well as garden ones. You mentioned butterfly gardening to try and support monarch butterflies, it's two simple things, have some milkweed for the caterpillars, and some flowers that have nectar for the adults. What's especially important is to have flowers that are still blooming in September and October when the big numbers of monarchs are heading to Mexico and migrating.
Matt Katz: You mentioned milkweed, can you explain why that's a good plan to have in order to support this species?
Mark Garland: I wish we'd call it something different, because weed in its name makes people think it's a bad thing. Milkweeds are native plants, there's a number of different species. A lot of garden centers and nurseries now have several species. The orange milkweed sometimes called butterfly weed is beautiful for dry areas, and swamp milkweed which doesn't need to be in a swamp has beautiful pink or white flowers.
The milkweed is able to incorporate into its system certain chemicals that the monarch caterpillars then incorporate into their bodies, which makes them toxic to vertebrates, birds, mammals, lizards can't eat monarch butterflies without getting sick. They've evolved to have this relationship with milkweed because it gives them protection from many potential predators.
Matt Katz: We're going to go to the phone lines, got a lot of callers with questions and experiences with these butterflies. Eric in Manhattan. Hi, Eric. Thanks for calling in.
Eric: Hello, thanks for taking my call.
Matt Katz: Sure thing. I understand that you have a milkweed story.
Eric: I do have a milkweed story. The last couple of weeks going to the 14th Street Farmers' Market I've been buying some milkweed, I come home and I find caterpillars on it. Now in my apartment, I have two Chrysalis and one caterpillar that I'm trying to keep the milkweed going as long as I can in its vases around the apartment to hatch some butterflies and put them out in the nature when it's done.
Matt Katz: Oh, that's great. Mark, what Eric should be doing, is that make sense? Is that what everybody should be doing?
Mark Garland: We can't actually raise enough in our houses to make a major impact on the population, but it's a wonderful activity. It's not that difficult to do. It's very inspirational if you're able to watch the whole process of a caterpillar growing and going through the metamorphosis. It's a great educational tool, a lot of school teachers will do it in the classroom.
It's a wonderful thing. Indeed, in the middle of Manhattan, you can support Monarch butterflies, whether it's that way you get them by accident when you're buying milkweed at the farmer's market or you have plants out on a balcony or a stoop or something and the monarchs that are migrating through because they will come right through the city may find it, may lay their eggs, may visit the flowers. Yes, that's a great thing. If you are really, really lucky, you'll be watching at the right moment when the Monarch bursts out of that chrysalis as an adult, it's a miraculous thing to see.
Matt Katz: Oh, that must be so cool. Scott in Basking Ridge. Hi, Scott. Thanks for calling in.
Scott: Oh, thanks for having me. Great show. Like the previous caller said, I've also done something like this. My wife and I are members of the North American Butterfly Association and we have a certified butterfly garden and also a monarch waypoint so they can have a place to rest as they're coming and going.
We raised over 36 monarch butterflies in aquariums in our house, and we got, like your previous caller said, we got eggs from the underside of milkweed plants, which we have a lot of on the property. I think your guest touched on it, but I was wondering if these are some programs that would make a difference. Even other than individuals doing it, are there any other large scale programs that might be able to help with something like this because it is fascinating to see it happen and then release them back into the environment?
Matt Katz: Thanks for the question, Scott.
Mark Garland: Now there's some evidence that raising monarchs inside doesn't end up with the healthiest monarchs. When you consider the estimate of the healthy population to migrate to Mexico should be in the range of a billion monarch butterflies, ideally, it's hard to imagine any mass rearing project could have a significant impact on that. Now, on the other hand, as I said, raising them inside can be an incredibly inspirational thing, a wonderful education tool, but of more value than bringing them inside and raising them is to maintain the proper habitat out there in the wild.
Fortunately enough, people have done that, especially along the Eastern seaboard, that the populations that migrate along the east coast are doing much better than the ones in the central part of the US. Different people have different opinions. My thought is, we can't possibly raise enough to have a significant impact on the population, but raising them inside is just a fabulous thing to watch.
Matt Katz: Let's go to another caller. Garrett in Cobble Hill. Hey Garrett, you're on WNYC.
Garrett: Hi, thanks for taking my call. I'm here in Cobble Hill, Brooklyn, and I got a garden. Been gardening for 30 years and had monarchs come through because I had buds and other plants they like. I can't grow milkweed because my garden is a little too shady, but I have noticed a decline. Over the past 10 years, I've mounted a personal campaign here in my neighborhood with the hardware stores to stop carrying Roundup.
I'd like to have your guest say something about the use of insecticides, especially in urban areas where it's not really necessary. I only use things like Nemo and insecticide soap and I have no problems in my garden. I'd like to get a response to that.
Matt Katz: Thanks, Garrett.
Mark Garland: Yes. That's to be commended. So many people with gardens want to take the easy way out. They'll hire a landscape company, which wants to take the easy way out and just use agricultural chemicals. In the widespread agricultural industry in the last 30 years, we've seen a dramatic increase in the amount of herbicide that's being used because there are genetically modified crops that are resistant to the herbicide.
Glyphosate, the active ingredient of Roundup is being used 10 times more than it was 30 years ago. The old farm fields if you think back 50 years ago, they'd have weeds along the edges and growing up between the corn plants and didn't impact the yields very much and among those weeds were milkweeds supporting monarchs and other native plants supporting other beneficial insects.
Yes, the use of agricultural chemicals, whether it's in a local garden or big scale is one of the things that the IUCN pointed to as part of the problem with the monarch population. Yes, here to be commended for avoiding the use of those toxic chemicals in your gardens.
Matt Katz: Wish we could get to all the callers who had questions and comments about butterflies. We got a ton, but one caller did want to tell us that there's a watershed butterfly festival going on this weekend in Pennington, New Jersey if you haven't gotten enough butterflies. Mark Garland, naturalist and butterfly expert, really appreciate you coming on WNYC again. Thanks.
Mark Garland: My pleasure.
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