Highland Mall Purple Martin Roost

After Danielle saw a post on the Birds of Texas Facebook page, we drove down to the Highland Mall in Austin to see the Purple Martin Roost that occurs here each summer. According to members of the Travis Audubon Society, which leads field trips to the mall, tens of thousands of martins roost in a few trees as they stage for their migration down to Brazil. The cluster of trees in which the martins are roosting this year is circled below

We arrived in the parking log behind Jack in the Box on the north side of the mall around 7:30 PM. Initially, we saw martins arriving in small group, swooping over our heads. This gave me some practice photographing birds in flight such as this female Purple Martin.

Canon EF 100-400mm f/4.5-5.6L - 400mm, f/7.1, 1/320s, ISO-400

As sunset approached, the waves of birds became larger and larger. Per the suggestion of the Travis Audubon Society, many spectators were sporting umbrellas to keep off the droppings. At sunset, the birds began to settle into the roosting trees. Unlike the spectacle of Mexican Free-tailed Bats, the birds do not stream like smoke trails. Rather, they circle and swoop in bunches, not nearly as tight as Starlings, but still very impressive. Especially so as I realized that these were Purple Martins which I have only ever seen in small groups.

Single frame extracted from iPhone 5 movie

Single frame extracted from Canon 60Da movie

This short video clip does not do justice to the number of birds. Next time, I need to bring a wide-angle lens!

After dark, we moved up closer to the roost for a better view and were able to stand right next to the low trees. Wow, it was like a solid wall of birds - each new arrival trying to find a spot to roost was greeted by irate neighbors staking out their spot. The air was thick with the smell of droppings which covered the ground below.

Canon EF 100-400mm f/4.5-5.6L - 135mm, f/8, 1/100s, ISO-800, (Flash)

Canon EF 100-400mm f/4.5-5.6L - 400mm, f/16, 1/100s, ISO-800, (Flash)

I notice that some of the birds have orange mouths and some pink mouths. I have read that baby martins have bright orange mouths that serve as a beacon for the parents to drop food into in their dark nest cavities. I wonder if the orange-mouthed bird below is a juvenile.

Canon EF 100-400mm f/4.5-5.6L - 400mm, f/8, 1/100s, ISO-800, (Flash)

Canon EF 100-400mm f/4.5-5.6L - 285mm, f/16, 1/100s, ISO-800, (Flash)

Canon EF 100-400mm f/4.5-5.6L - 285mm, f/16, 1/100s, ISO-800, (Flash)

On the whole, an amazingly social bunch of birds to tolerate such close proximity. They eventually began to settled down for the night as we and the last of the spectators packed up around 9:30 PM.