Gabriel Willow.

"The piers were slated to be at least partially demolished," Willow said, "but the presence of the terns influenced the decision to keep them. Overall common terns are declining in the United States. They are a New York State Threatened Species. However, with the presence of this colony, they would seem to be increasing in New York City."

Common terns.

He said that common terns breed between Newfoundland in Canada, south along the coast to South Carolina. They winter in Central and South America, flying as far south as northern Argentina. This June, scientists from the New York City Audubon Society captured a common tern nesting on Governors Island that had been tagged in Argentina in March.

The boat picked up speed as it traversed New York harbor's upper bay and crossed under the Verrazano-Narrows Bridge to the lower bay. It paused at Hoffman and Swinburne Islands, two man-made islands that lie between Staten Island and Brooklyn. Once used to quarantine immigrants to New York City who had arrived by ship, they are now bird colonies, largely populated by gulls, cormorants and egrets.  

Then, with some distance still to go before arriving at Jamaica Bay, the Water Taxi sprinted past Coney Island toward Breezy Point, Queens at the western end of the Rockaway peninsula. On this tranquil summer afternoon, people sat in their lawn chairs on the beach with their sailboats and motor boats tied up in the shallow water. Behind them, were houses draped with bunting and American flags. Some of them were still being repaired after flooding and fires caused by Superstorm Sandy almost two years ago.     

Peregrine falcon on the Gil Hodges Memorial Bridge.

At the Gil Hodges Memorial Bridge that crosses Rockaway Inlet, connecting the Rockaway Peninsula with the Marine Park neighborhood in Brooklyn, the boat paused. Willow said that peregrine falcons nest on top of the bridge and that they might be visible. They were.

There are 16 pairs in New York City, the largest concentration of peregrine falcons in the world, according to Willow. Remarkable predators who can swoop down on a pigeon or other prey at speeds of up to 240 miles per hour, catching the other bird in mid-air and killing it with a well-placed bite to its neck, the peregrine falcons were wiped out in the eastern United States by the pesticide, DDT. It weakened their egg shells so that the adult birds literally crushed the eggs when they sat on them as they waited for them to hatch. After DDT was banned in the late 1970s, peregrine falcons were bred in captivity and re-released in the wild to restore the population.

Peregrine falcons mate for life and return to the same nesting sites year after year. In the wild, peregrines can live up to 15.5 years.   

After passing another bridge used by the subway line that services the Rockaway Peninsula, the expanse of Jamaica Bay opened in front of the visitors, its saltmarshes and mudflats bordering low-lying islands.   

The bay connects to the Atlantic Ocean via Rockaway Inlet, making its water both saline and, in places, brackish.  

Although it is now only 30 percent of its original size (JFK International Airport and Floyd Bennett Field snatched much of Jamaica Bay's original acreage), most of Jamaica Bay has been protected since 1972 as part of the Gateway National Recreation Area. It is a Garden of Eden for many kinds of wildlife. It is visited by, or home to, more than 325 species of birds, 50 species of butterflies and 100 species of finfish.    

Laughing gull.

The group aboard the New York Water Taxi spotted great egrets and snowy egrets prowling at the water's edge. American oystercatchers, striking in black-and-white plumage with orange beaks, hunted for dinner in the shallows. Common terns flew overhead along with the four kinds of gulls that are found in New York harbor, among them, laughing gulls with coal-black heads.

"They breed in tidal marshes, so Jamaica Bay is their primary breeding ground in New York City," Willow said, "but they can be seen and heard throughout the city from April through October or so."    

A great blue heron also made its way over Jamaica Bay, an unusual sight in the summertime. "They pass through in migration and in winter, but they breed in freshwater swamps with trees, so they're not usually around here in summer," Willow observed.  

By the time the boat turned around to head back to Manhattan, the sun was setting. Some fishermen were still casting their lines from small motor boats anchored in the bay, but the bird fishers had mostly called it quits for the night.  

Jamaica Bay and the Manhattan skyline.

The skyline of Lower Manhattan was visible above the saltmarshes. "We used to say that Jamaica Bay was the back door to the city," said Willow. "Now, we know it's the front door."

Jamaica Bay's saltmarshes and native spartina grasses (Spartina alterniflora and Spartina patens), heedlessly destroyed by previous generations, are now known to be essential protections for New York City's populous neighborhoods.   

On July 17, the National Park Service, which administers the Gateway National Recreation Area, announced that the Science and Resilience Institute at Jamaica Bay had been awarded $3.6 million from the Department of the Interior's Hurricane Sandy Mitigation Funding to support 10 research projects. The institute is a collaboration between the National Park Service, New York City and a consortium of nine top-tier research institutions headed by the City University of New York. 

The grant from the Department of the Interior will advance knowledge of resilience in urban coastal ecosystems, with work beginning immediately and continuing through 2016.

At one time, wetlands like those of Jamaica Bay ringed the islands of New York harbor. Given climate change and rising sea levels, a visit to Jamaica Bay may reveal both the city's past and its future.  

- Terese Loeb Kreuzer 

The next New York Water Taxi/New York City Audubon Society ecocruise to Jamaica Bay takes place on Sunday, Aug. 10, followed by one on Aug. 17. The cruise is three hours long (6 p.m. to 9 p.m.). On Sundays, July 20 and July 27, Gabriel Willow will lead a two-hour ecocruise, "Bridges and Birds," to Hoffman and Swinburne Islands. (Time: 7 p.m. to 9 p.m.) On Sunday, Aug. 3, he leads a two-hour cruise to the Brothers Islands in the East River. For more information and to buy tickets, click here.