Purple martins return to Austin

Driving the news: The Travis Audubon's popular (and free) purple martin parties kick off Friday in Round Rock and continue each Friday and Saturday through Aug. 9.

• To get the best view, visitors should head to 3115 S. I-35 Frontage Road and follow Travis Audubon's parking and viewing guide.
• The weekend gatherings draw hundreds of spectators.

How it works: Purple Martins, identified by their indigo feathers and long, tapered wings, spend each summer in the Austin area as they prepare to migrate to South America.

• After eating insects all day, the birds put on a show, making a swirling pattern in the air as they head into their roosting sites for the night.
• As many as 100,000 purple martins will cram into one tree for the night.

• You'll start to see them trickle in around 8:30pm, as the sun begins to set.

Zoom in: Austin is home to a major roost site, where thousands of birds gather each summer near Round Rock's La Frontera shopping center.

• The birds also roost at other sites around the city, including resident Laura Joseph's home in South Austin. Joseph has made her property a purple martin haven for decades, using plastic, human-made housing.

The bottom line: Bring an umbrella or a hat. You'll get pooped on, but it's worth it.