Issues of the Environment: Exploring and tracking Ann Arbor's butterfly population
- For the past 17 years, a handful of citizen-science volunteers have been dutifully documenting the species and abundance of butterflies in Ann Arbor Park, Greenview Nature Area. John Swales, professor emeritus of linguistics, began systematically documenting numbers and types of butterflies on his own nearly two decades ago as an amateur observer with no special training.
- This month, he and two other retired university professionals published a compilation of their citizen-science data and an account that demonstrates why long-term projects that track local species are not only uniquely valuable to the historic record, but also potentially informative for future conservation decisions.
- Conservation biologist Scott Hoffman Black, executive director of the Xerces Society for Invertebrate Conservation, says that citizen-science surveys for butterflies are “elegant” in its combination of academic and community data. “It adds to our growing understanding of what’s going on with insects and insect decline across the globe,” says Black, who wasn’t involved in the study. “The overall conclusion that climate is a major driver when it comes to butterfly decline is the important takeaway.”
- Aside from the value of the data, the book’s authors hope to inspire other amateur scientists to collect data for research. Point-in-time data spanning decades can capture environmental changes that are subtle but telling. Swales and his co-authors were drawn to butterflies partially because they are elusive and lovely, but also because butterflies are sensitive to environmental changes. Butterflies are environmental indicators, and their movements and migration patterns are altered with environmental changes.
- Many species of butterflies that can be observed locally are declining at the population level due to habitat loss, pesticide use, agricultural monoculture, and climate change. However, citizen-science illuminated some good news for the Monarch butterfly. This June, citizen-science and academic population studies spanning decades showed that while the wintering population of Monarchs has plummeted, the eastern population of Monarch butterflies appears to be increasing. The butterfly seems to be having good breeding success in the United States and Canada during the summer that is making up for the die-offs during the winter in Mexico due to habitat destruction.
- “Therefore, we offer this booklet as an encouragement to those who might otherwise not be inclined to turn their years of natural observations into substantive, useful and publicly available reports”, they write. The book is not a field guide, but it does give species specific accounts as to how and where to find butterflies in the park and elsewhere. Tips include looking low for smaller species that might be overlooked, becoming aware of the host plant associated with certain species, and which species are found locally at different times of the year.
- Marcy Breslow, co-author of the new book “The Butterflies of Our Local Park” and local citizen-science volunteer, began her foray into butterflying a couple of years ago as a volunteer data collector in one of Ann Arbor’s Natural Area Preservation programs. Since her retirement, she has developed a passion for finding and documenting local butterflies with citizen-science.
David Fair: This is 89 one WEMU, and welcome to another edition of Issues of the Environment. One of the great parts about this time of year is the meditative practice of watching butterflies live their lives while decorating ours. I'm David Fair, and it's been my personal experience that I've seen less and less of our flittering friends over the past several years. That is, of course, anecdotal. But today, we'll explore the butterflies in our community and look into what's happening with these vital pollinators with a citizen expert. Marcy Breslow is coauthor of a book published this month entitled "The Butterflies of Our Local Park." It documents the findings and experiences of citizen science volunteers observing and monitoring butterflies in Ann Arbor's Greenview Nature Area. Marcy, thank you so much for making time for us today.
Marcy Breslow: Well, thank you.
David Fair: The research for this book began some 17 years ago and was launched by one of your coauthors, John Swales. At what point did you become involved?
Marcy Breslow: Actually, just last year. I met John and Judy at Greenview while I was doing butterfly monitoring for Natural Area Preservation for the City of Ann Arbor and was frustrated that I did not know that much. And so, John and I met and I globbed onto them and have been going out with them ever since.
David Fair: The Judy you referred to is Judy Lobato, the other coauthor of the book. Were you interactive with John and Judy while working on campus, or is it the butterflies that brought you together?
Marcy Breslow: It's the butterflies. I don't know when John and Judy met. I believe it was about 20 years ago and probably to do with birding.
David Fair: So, is the reasoning behind each of your interest in butterflies similar in nature, or did you each arrived there by taking different paths?
Marcy Breslow: Well, I think, to a great extent, it was similar because we were all longtime nature lovers and interested in what's around us and knowing who is who out there in the world. But I didn't really think that much about counting until I volunteered for NAP. John has been doing birding and butterflies for many, many years, and I can't remember if you mentioned that he was coauthor of "The Birds of Washtenaw County" back in the nineties. And Judy owns a farm in Scio Township. So, we all come from similar and yet somewhat different backgrounds.
David Fair: 89 one WEMU's Issues of the Environment continues. And today, we're talking with Marcy Breslow. She is one of the three authors of the book, "The Butterflies of Our Local Park." It focuses on citizen science volunteers and their work in Ann Arbor's Greenview Nature Area. I mentioned at the outset, Marcy, that I seem to be experiencing less interaction with butterflies in my rather suburban life. Does that bear itself out in the areas the three of you were exploring?
Marcy Breslow: It's not clear, because the numbers of butterflies over, like, fiveish-year periods--during the survey period--have remained roughly the same at Greenview. But there are huge variations from year to year. For instance, in 2008, they found over 2,300 individual butterflies. The very next year, in 2009, they found just over a thousand. And we don't really know the explanation. Now, one thing about Greenview that is different from many other places is that there has been extensive effort by friends of Greenview and Pioneer Woods nature areas to maintain the meadow as a meadow, as that is not particularly common. And many of the places in the county have become overrun with woody plants and invasives. So, Greenview is kind of special in that regard, even though its environment is--in general--is not that special in the area.
David Fair: As you conduct these counts and look at what you're seeing, assess it, and put it together, are you sharing that with the scientific community proper, so that we maybe get further understanding of the human and climate impacts on butterflies?
Marcy Breslow: Yes. We share the Greenview counts with the Natural Area Preservation. So, they, in addition to having the NAP surveys, which are usually only about six with a very specified route which happen to be different at Greenview from the one that John, Judy and I take, I send them the information, and John was sending them the information before that. And the information is also sent to at a state level and to North American Butterfly Association, which keeps counts. And then, NAP also sponsors several counts per year nationwide and up to, like, 450 different locations.
David Fair: In the conversations you have among yourselves, are you starting to come to some conclusions as to the primary reasons for the declines in some of the butterfly populations?
Marcy Breslow: Yes. Habitat loss is huge, and that is intertwined with the invasives that don't nourish them or provide a good habitat for their eggs. We're really concerned about climate change. Some of the immigrants that we used to see fairly often from the north we don't see anymore. One of those was a Mildridge Tortoise Shell, which apparently was fairly common in, like, 2008, but hasn't been seen in the county since maybe 2011. The weather, perhaps even the more torrential rains, could be a problem. And pesticides, of course, are a problem once again.
David Fair: We're talking with Marcy Breslow on WEMU's Issues of the Environment. She is one of three authors of the book published this month called "The Butterflies of Our Local Park" and focuses on citizen science volunteers and their work in Ann Arbor's Greenview Nature Area. So, as you assess the situation, as you've discovered personally over the last three years and in sharing research over the past 17, what are you most optimistic and pessimistic about the future of local butterflies?
Marcy Breslow: Well, I'm optimistic because this area--the county--has been very fortunate in that we have a lot of nature preserves. And so, those provide refuge for butterflies and other insects that pollinate and nourish birds and other creatures. So, there is some optimism there, and there are a lot of citizens who have become interested in trying to maintain habitats and improve the environment. So, that's also very optimistic. Climate change is a concern, and, at least in Greenview, although we're not entirely sure that the problem, but we have seen, we think, a slow decline in certain kinds of butterflies. For instance, the Littlewood, which has finished its first roof, or we wouldn't be seeing them right now. They hope to again--the numbers do seem to be down over the last several years. But we have some new species that didn't used to exist that have become resident. There are two in particular: the Common Ringlet, which, oddly enough, is an immigrant from, I think, the North, or at least sort of northeast. And the Common Shepherd's Skipper, which used to be abundant only in, like, Virginia and below and used to be seen clearly as a migrant late in the season has now fairly established itself as a resident at Greenview. I saw it too in May this year, so that's pretty exciting.
David Fair: Again, yeah, that has to be exciting when you stumble upon something that once wasn't there, and now it is. So, along that same line as our time together runs out for the day, do you have a favorite butterfly experience to this point?
Marcy Breslow: Mmm. Yes. Last year at Greenview was my first time ever seeing a Baltimore Checkerspot, and I had seen pictures of them. They're black, orange, and white. And there's one actually on the front cover of the book, and it was an absolute thrill to see it. It was at a distance through binoculars, but still. And I kind of fell in love from that. Oh, my gosh, this is fantastic. And I've seen two this year, and, actually, they are out right now. I found two last Saturday at Greenview. And there's another local spot, Liberty Pond Nature Area in Scio Township, which apparently have the most Baltimore Checkerspots in the entire county. So, if people want to try and see them, they can check those places out.
David Fair: Well, Marcy, I thank you not only for sharing your time today but sharing your passion as well.
Marcy Breslow: Well, you're more than welcome, and thank you for your interest.
David Fair: That is Marcy Breslow, coauthor of a book published this month entitled "The Butterflies of Our Local Park." You can find it at bookstores and order it online. We'll have all the information you need on our web site at WEMU dot org. Issues of the Environment is produced in partnership with the office of the Washtenaw County Water Resources Commissioner. And you hear it every Wednesday. I'm David Fair, and this is 89 one WEMU FM and HD one Ypsilanti.
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