A shadowy flight, around the Ft. Sam Houston national cemetery and the adjacent golf course. They’re not bats, they’re nighthawks, and in late summertime they congregate to cruise low over the marble headstones in the gathering dusk.
Despite their name, nighthawks are most active not at night, technically, but around dusk — they need a bit of light to target flying insects, their preferred prey. They often congregate around street lamps and lighted parking lots, and their calling is one of those unremarked background sounds that typifies summer evenings in South Texas:
The lesser nighthawk, however, is more of a local specialty; normally a resident of southwestern deserts and washes, it has found a similar breeding habitat on the flat asphalt rooftops and tarmacs of Fort Sam and nearby neighborhoods, where it scrapes out shallow nest sites from pebbles and tar. If you’re blessed with a flat roof and window screens — or if you’ve spent evenings around the Pearl Brewery, the Riverwalk and the museums near Brackenridge Park, you may already be somewhat familiar with the sound of its hollow humming and giggling around the nest.
By early August, many local nighthawks have finished nesting, and as the sun sets they can be seen making their way across Harry Wurzbach to Fort Sam Houston to pursue flocks of insects over the golf course and cemetery grounds — creating a big swirl of batlike fluttering wings for a few astonishing nights.
During the 2011-2013 drought the phenomenon was especially noticeable — perhaps due to the abundance of insects over the comparatively well-watered grounds of Fort Sam, thanks to its recycled water supply.
Common nighthawk recording by Andrew Spencer, Yellowjacket Canyon, Colorado 5-27-2007
Lesser Nighthawk by Bobby Wilcox, La Paz County Arizona 5-5-2015