Many people are familiar with the Mexican free-tailed bats who live in and around the Austin area, especially those inhabiting the world’s largest urban bat colony found under the Ann W. Richard Congress Avenue Bridge.  Austinites and tourists thrill at the site of the 1.5 million bats leaving their roost late each summer day for their nightly insect foraging, before migrating to Mexico for winter. Less well-known, but also a remarkable natural event, is the annual migration of the Purple Martins, Progne subis.

Photo courtesy of The Cornell Lab of Ornithology  All About Birds

The Purple Martin is North America’s largest swallow.  Like many other species of birds, they winter in South America, but breed in North America during spring and summer, migrating back and forth during the course of their lives.  Purple Martins are gregarious birds and it’s long  known that they’re comfortable around human habitation. According to the Audubon Society, Native Americans learned that the Martins were valuable assets to their crops and placed hollowed gourds to encourage the Martins to nest nearby.  The Martins chased crows away from crops and vultures away from drying meat.   In modern times, most Purple Martins nest in human provided housing during their breeding season throughout a large area of North America. From July to early August,  they leave their individual nesting sites and converge in enormous roosts preparing for their migration to South America for winter.

Here in Austin,  Purple Martins gather by the hundreds of thousands, roosting in trees along I-35.  Austin is located along one of three major flyways for this Neotropical bird. This year, the birds decided to change things up a bit and instead of roosting in oak trees at Highland Mall, as they have for a couple of years, they’re roosting in trees at the nearby Capital Plaza Shopping Center.

At about 8pm, you can witness a few birds in the air,

…and a few Austinites on the parking lot, settling into their lawn chairs, getting ready for the show.

Travis Audubon  hosts Purple Martin Parties on weekend evenings from mid-July to early August and have knowledgeable volunteers ready to answer questions about these cool birds and their life cycle. The evening we visited, one of the volunteers told us that there were an estimated 400,000 birds roosting for the night. It takes a while for the action to kick into gear, but by sundown, there are thousands of birds congregating above the parking lot.

Swirling in flocks, the Martins fly in unison, flitting into one tree, then another, seemingly indecisive about where to rest their weary beaks for the night.

The birds are chatty, beautiful and swift flyers, and downright doodee dangerous if you’re standing nearby and don’t hold an umbrella over, or sport a hat on your vulnerable head.

If you know what I mean.

I always wear a hat when I watch the Martins.

The Husband didn’t wear a hat this year and he had to wash his hair when we came home that evening.

If you know what I mean.

As more birds gather, they swoop and sway in the air and by sundown, many are perched in the trees for the night.

I ventured closer to get photos of the roosting birds.

Yes, I was wearing my hat.

It was very windy that particular evening and I had a hard time getting clear shots of the birds in the swaying branches.

Most of these birds are females and fledgling chicks, though there are males here too. The male Purple Martin is a deep, iridescent purple and the female is drab, with a light gray chest and white tummy.

Martins are insectivores who fly fast and high, catching prey on the wing.  They feed during the day, resting at night.

I once placed a Purple Martin house on our property, but it was an abject failure at attracting these lovely birds.  Martins like open space in which to fly and hunt and there are too many large trees around my home to attract these birds.  Most Martins nest in human provided houses, though Martin lovers must contend with European Starlings and House Sparrows who will aggressively displace Purple Martins from their homes. Those wishing to attract Martins must be vigilant in removing the invasive birds if they want Martins to breed.  Older, male scout Purple Martins arrive as early as February to check out  nesting sites, followed a few weeks later by the females and the younger males.  They are fun and interesting to observe during their breeding period and fascinating as they prepare for their trip to South America.

Purple Martin magic.

Ain’t nature grand?

Thanks to the enthusiastic Travis Audubon members who teach others about the importance of birds, to the businesses who encourage visitors to view the roosting Martins, and to the many Purple Martin lovers who host them during breeding season. You’re all part of the solution.

Have a good migration, Purple Martins, and a safe trip back next February.  Swing by and say “Hi!”.