Along the Atlantic coast, summer afternoons arrive on the wings of the glossy ibis (Plegadis falcinellus). These dark birds seem to appear magically, suddenly haunting shallow mud flats and wet meadows where just minutes earlier none had been.
Johann Schumacher Even in the velvety late afternoon light, it is hard to call the glossy ibis beautiful. It seems as if every ibis hides an inner dinosaur. Up close, there is something primitive about them, almost vulture-like, and even in flight - where their grace is on display to its greatest visual effect - their long outstretched necks seem to hark back to something more ancient than lovely.
Ibises' charms are never wasted on children, though, who are generally more familia r with dinosaur books than field guides, and frequently make comments like: “Look, Mommy, a pterodactyl!â€
They probably are not far from right, and theories about modern birds' reptilian ancestry aside, the ibis's ancient lineage plays nicely against a 21st-century New York City skyline.
Until recently ibises were not a part of this modern landscape. Indeed, for a beginning bird-watcher in the early 1970s, an ibis was a bird of some note, worth a visit to Jamaica Bay in Queens or Pelham Bay in the Bronx. Glossy ibises first arrived in South America from Africa in the mid-19th century. They have been steadily expanding their range northward since. The bird is quite cosmopolitan and can be found in Europe, Asia, Africa and Australia.
In flight, an ibis is easily distinguished from other waders like herons and egrets, as it flies with its neck outstretched, an odd posture that serves to further emphasize its long, down -swept bill.
Johann Schumacher The birds use their bills as highly effective probing tools, searching the soft mud with their heads bobbing up and down like sewing machines. When the bill hits the bird's preferred prey (crustaceans, worms, snakes, small fish and mollusks), the unfortunate food item is quickly dispatched with a simple nod of the head. At times, just the tip of a hapless tail remains briefly in view until it, too, is maneuvered down the bird's long gullet.
At a distance ibises appear to be uniformly dark, which accounts for one of their early common names, black curlew. When observed through binoculars or a spotting scope, however, the birds are a rich chestnut brown, with a greenish or purplish iridescenc e spreading across their shoulders, lower backs and wings. Their interesting behaviors and unusual colors have sold many pairs of binoculars over time, as the bird fascinates many a neophyte bird-watcher.
Glossies have made themselves at home along our shorelines and now breed within New York City. The birds build twig nests in low shrubs on the city's remote islands, generally in mixed colonies of other long-legged wading birds like egrets and herons. Ibises depend upon soft mud and open water for survival, so come September, the birds can be observed making their way southbound to the Carolinas and beyond, well ahead of fall's first frosts.
A version of this article appeared in print on 06/30/2013, on page MB4 of the NewYork edition with the headline: ‘Look, Mommy, a Pterodactyl!'.