It’s snake-bird season in North Carolina. The ostrich-necked, fan-tailed fish hunter also known as a water turkey, or anhinga, typically resides in the bayous of Louisiana and Florida. However, it will migrate north in the summer if it finds a swampy, low-lying lake with trees to perch onnot around, but inside the lake. As the Audubon Society notes on its Web site, “The more retired and secluded the spot, the more willingly does the snake-bird remain about it.”

Falls Lake, built by the U.S. Army Corps of Engineers in the early 1980s to prevent flooding and provide a water source for the region, is a summer refuge for snake-birds. Navigating the muddy brown waters, our motorboat passes a flock of them gathered on the branches of dead trees. Three birds are perched on what looks like the points to a wooden crown, barely jutting through the low-lying waters near Lick Creek.

As they lift off, they do not go far. Unlike most aquatic birds, their feathers do not repel water; instead, as they dive, horizontally, they allow the water to drag them down, until they just skim the surface, like a river snake. If they need to, they will completely submerge.

After we gawk at the snake-birds, the Neuse Riverkeeper boat stalls in the lake near Lick Creek, where deposits of silt and mud cause the lake’s depth to quickly fluctuate from 15 feet to 2 feet. As the motor restarts, greenish-brown muck shatters the reflective pool, and power lines in the distance reminds us that we are in the middle of a metropolitan area.

The Raleigh-Durham area has not always been kind to Falls Lake. Since the late 1990s, three streams snaking into East DurhamEllerbee, Lick and Little creekshave been classified as impaired by the Environmental Protection Agency due to runoff from development. Roads and roofs and other impervious surfaces are the largest sources of pollution; they prevent water from being naturally cleansed of pollutants, which then drain into the lake and kill or damage aquatic life.

Floating by stumps and strange birds, we look to the water’s edge, where trees’ roots are exposed to a shoreline that looks like a mountain cliffa reminder of how quickly this man-made lake can evaporate.

The drive back to Durham is remarkably rural: farmhouses and modular homes are set back from gravel driveways. Mailboxes begin to appear, though in the shapes of tractors and letter-devouring bass. Someone has hand-printed a “Yard Sale” sign on cardboard and slung it over a picket fence. A few scattered headstones in a clearing along the road lie kitty-corner to a church, and down the road from a golf course. This is the country, it feels like, and yet I am driving between Durham and the state capitalaway from the 28-mile long water source that, last year, nearly ran dry.

Falls Lake info: N.C. State Parks and U.S. Army Corps of Engineers