Last week, we hosted a monarch tagging field trip at Patrick Marsh. Twenty volunteers came out to catch, tag, and release monarchs before they migrate to Mexico.
Tagging monarchs is part of a citizen science project that spans the continent. When the monarchs reach central Mexico, local guides and farmers collect the tags and report them to Monarch Watch. This project helps us understand how monarchs migrate and reproduce so we can protect their habitat in meaningful ways.
My favorite part of this work is connecting with an international community of land stewards. The farmers who report these tags work on ejidos, which are communal agricultural lands. From one community land project to another, pa’lante!
A tagged monarch is released. Photo by Sterling Ruemmler.
How Monarchs and Milkweeds Evolved Together
Monarchs and milkweeds have a special relationship. Monarch larvae rely exclusively on the milkweed genus for food, despite a toxin the plants produce to keep animals and insects away. Monarchs have not only evolved to eat these poisonous plants, but also to use its toxins for defense.
Monarch butterflies are an endangered species. Habitat loss in both their breeding grounds and overwintering sites is the primary driver of their decline. At Westport Prairie, we’re the proud steward of three species of milkweed, though there are 13 native milkweeds in the state. We’ll give a Groundswell hat to the first person who knows which three!
Researcher Jillian Neece at Westport Prairie. Photo by Timon Keller.
Westport Prairie: A Host Site for Milkweed Research
If you’ve walked the drumlin at Westport Prairie this summer, you may have noticed flags and cages scattered across the hillside. These mark Jillian Neece’s graduate research at UW-Madison where she’s studying milkweed pollination.
She’s excluded certain pollinators from milkweed flowers with mesh of varying sizes, and is now testing the seeds for successful pollination as they mature. In essence, Jillian is working to understand which insects actually pollinate milkweeds and whether milkweeds depend exclusively on larger insects to set seed.
In Jillian’s words, “as populations of large pollinators that commonly visit milkweeds such as monarchs and bumblebees decline, the effect on milkweed seed production remains unknown.”
For further reading about monarch butterflies, here are two publications we enjoy: A Wing and a Prayer by Mark Leviton in this month’s edition of The Sun and A Tale of Coevolution: Monarchs and Milkweed by Clara Jordan.
Short Green Milkweed. Photo by Timon Keller.
Come collect milkweed pods with us!
Finally, we’d like to invite you to collect prairie seed with us. Seed collection is a great volunteer opportunity for beginners. We’ll teach you everything you need to know, and you’ll almost certainly leave knowing a new plant.
Meet us at Westport Prairie at 5208 Bong Road in Waunakee on these dates:
September
Wednesday, September 30, 9–11 a.m.
October
Wednesday, October 14, 9–11a.m.
Thursday, October 15, 4–6 p.m.
Thursday, October 29, 4–6 p.m.
To register for these events, please visit groundswellconservancy.org/events.
We also collect seed at our regular outdoor volunteering events, which take place at Westport Prairie each second Saturday of the month from 9–11:30 a.m. Sign up to receive outdoor volunteering emails at groundswellconservancy.org/get-involved/outdoor-volunteering.
Volunteers at Westport Prairie in September 2025. Photo by Roberta Herschleb.
Take care,
Sam Douglass
Farm & Land Manager
P.S. If this work inspires you, please consider making a gift to Groundswell to keep the momentum going!