Under the fluorescent light of a Discount Tire sign, hundreds of people gathered in a strip mall parking lot near Austin, Texas. In between chats with volunteer naturalists, many lounged in lawn chairs or lay on blankets atop the warm concrete and grass. Then as dusk turned to dark, the show began. A chorus of chirps filled the air, and a cloud of swirling birds descended onto the trees before the crowd, who were ready with their poop-shielding hats and umbrellas.
The guests of honor? Hundreds of thousands of Purple Martins settling in to roost. For decades, birders have congregated in the area’s parking lots to watch the phenomenon. In 2010 Travis Audubon began organizing formal Purple Martin parties from mid-July to early August. The events now attract up to 700 annual attendees and have inspired similar celebrations in other cities. “A lot of people who would not consider themselves to be birders—or maybe even nature lovers—come out to our parties,” says Shelia Hargis, board president of Travis Audubon.
With their cheery calls and ultramarine plumage, Purple Martins are a familiar sight for many in the United States. In early spring, the aerial insectivores migrate from South America—primarily the Brazilian Amazon—to nest and raise young, breeding across much of eastern North America and in patches of the Southwest and Pacific Coast. But before returning south as summer ends, these birds, like many swallows and swifts, congregate in giant roosts. The behavior is a key part of their life cycle, says Joe Siegrist, president of the nonprofit Purple Martin Conservation Association. By staging in large numbers, martins seek safety from predators, and fledglings learn where to forage from older birds. The gatherings typically coalesce in midsummer; over weeks, they build in size as more birds fledge from their nests.
Many roosts in the southern United States occur in urban parking lots: perfect settings for watch parties. From above, these concrete and asphalt expanses may look like the wetlands where birds would traditionally shelter. “A patch of trees in the middle of a parking lot mimics a patch of trees in the middle of water,” Siegrist says.
However, despite their huge head counts, roosts can be surprisingly difficult to locate. The birds flurry only at sunset and sunrise, and they don’t necessarily use the same trees year after year. So for a Purple Martin party planner, securing a venue may take days or weeks of searching, says Susanne Harm, a long-time volunteer for Travis Audubon. In mornings and evenings, she and another volunteer will drive north of Austin to stake out activity. If they can’t spot any martins from the ground, data offer clues: Roosting flocks are large enough to show up on weather radars, blooming into airborne donuts as they depart en masse.
Once she finds a roost, it’s time to court local businesses. “The first thing I do is educate them about this massive tornado of birds that will soon be descending,” says Harm. Such outreach is important because not everyone is thrilled when swarms of martins sweep into their neighborhoods; just this year, Travis Audubon almost canceled its parties due to a lack of buy-in from property managers. Meanwhile, in Nashville, Tennessee, when roosting martins blanketed the downtown symphony center with droppings in 2020, the staff enlisted pest control to get the birds to move on. Conservationists persuaded them to call off the effort—and set about inspiring an attitude shift.
In the following years, they launched a major advocacy effort, stationing volunteers at summer roosts to educate people about the species. After martins started roosting at the city’s Nissan Stadium, a series of Purple Martin parties there in 2024 was a grand success, drawing crowds of people to watch about 150,000 martins. “[The martins] create their own breeze, and they’re vocalizing. It’s almost spiritual,” says Laura Cook, bird research coordinator with Friends of Warner Parks, which cohosted the event.
Such spectacles can inspire action as well as awe. Travis Audubon uses the parties to educate people about how they can support birds, Hargis says, and some attendees go on to become Purple Martin “landlords”: devoted volunteers who hang groups of gourds or set up multistory condos to house colonies of the birds. East of the Rockies, Purple Martins now breed almost exclusively in these structures as tree cavities where they historically nested have dwindled.
Many landlords also provide data on their visitors to the Purple Martin Conservation Association, logging when martin parents first arrive and how many chicks they successfully raise. “It’s hugely valuable to what we’re doing as scientists,” says Maria Stager, a biologist at the University of Massachusetts Amherst who used the data to study the impacts of severe weather on the species. Volunteers play a key role in tracking down roost sites, too, which can help identify places to protect. While radar images suggest that around 250 roosts exist across the martins’ range in North America, most of their exact locations remain unknown.
As Purple Martin populations see widespread declines, likely tied to habitat loss and invasive species, conservationists hope that sharing more about the birds can help build better coexistence. For partygoers who flock to parking lots and downtown streets, roosting martins offer an incredible display—and a deeper connection with a familiar species. “It’s pretty amazing that they have this association with humans,” Cook says. “They’re the people’s bird.”
This story originally ran in the Fall 2026 issue as “Welcome Party.” To receive our print magazine, become a member by making a donation today.
