Vultures are a common sight in Houston, and indeed all over the US. We often see them gliding around looking for food. Roadkill is a great attraction. A couple of years ago we saw a gang of about 15 around what was probably a squashed squirrel, seizing the opportunities to grab a bite between the traffic.
A large group hangs around the Terrey Hershey park near the I10, and seem happy to pose for photographs.
Mostly you see the distinctive outline as they soar through the air, seeking out their staple food, carrion. The one below, which I took some time ago in southern Texas, is a turkey vulture, which you can tell by the red head.