One sign of the coming fall in North Carolina is the swirl of thousands of small birds that circle large chimneys or smokestacks each evening before dropping down inside to roost for the night.

The mesmerizing pre-migration ritual of the chimney swift is becoming rarer as the bird’s population continues a long decline that began in the 1960s. While it’s not clear how much of that can be blamed on a lack of roosting places, few modern buildings have big chimneys or smokestacks, and people who are concerned about the birds try to preserve as many of the existing ones as possible.

Which is why John Connors of Wake Audubon approached the owners of the Transfer Co. Food Hall on the east side of downtown Raleigh. The food hall, which opened earlier this year at 500 E. Davie St., was built in 1926 as the garage for the Carolina Coach Company, where buses were stored and repaired, and has a square brick chimney on the south end overlooking what is now a patio with outdoor tables.

Read the full story in the Raleigh News & Observer.