07/09/2026
200 nesting terrapins/hour- sounds like the perfect day!
Every summer, hundreds of diamondback terrapins crawl out of Jamaica Bay and onto the runways at John F. Kennedy International Airport to lay their eggs. Pilots report turtles to the air traffic control tower. Flights are delayed. Port Authority wildlife staff sprint across the tarmac collecting them by hand. On peak days, nearly 200 terrapins have been documented nesting in a single hour.
Nobody planned this. When JFK was built in the 1940s, engineers filled the marshland at the edge of Jamaica Bay with sand and gravel to create the runway infrastructure. That sandy fill, elevated above the high tide line, accidentally became the best nesting habitat for diamondback terrapins in the entire bay. Female terrapins need loose, sandy soil above the tidal flood zone to dig nests and bury their eggs. The airport gave them exactly that, mile after mile of it, surrounded by chain-link perimeter fencing that happens to keep raccoons out.
The raccoons matter. In the surrounding Jamaica Bay Wildlife Refuge, raccoons are the primary predator of terrapin nests, digging up eggs and eating hatchlings. Inside the airport perimeter, the security fencing excludes them. A turtle that nests at JFK has a better chance of her eggs surviving than a turtle that nests in the adjacent national park. In 2008, a canine distemper outbreak killed a significant number of raccoons in the Jamaica Bay area, which further reduced nest predation. Terrapin numbers at JFK climbed sharply in the years that followed. By 2012, airport staff collected, marked, and released more than 1,300 terrapins during a six-week period. The turtles were not invading the airport. They were choosing it.
The problems started when they chose the runways. Runway 4L runs along the edge of Jamaica Bay. At high tide in June and July, female terrapins haul themselves out of the water and head for the nearest sandy ground above the tideline. Some of them cross active taxiways and runways to reach it. In 2011, Laura Francoeur, the Port Authority's chief wildlife biologist, watched 20 females crawl across the tarmac at once while aircraft operations scrambled to clear them. Pilots discussed the terrapins on the radio with the control tower. Every time staff reopened the runway, another turtle appeared. The delay was only 10 to 15 minutes, but at JFK, 15 minutes of runway closure cascades into delays at airports across the country and around the world. JetBlue alerted customers with a tweet and the hashtag . A passenger replied that it was the only delay excuse they had ever found endearing.
The Port Authority's response was not to remove the turtles or destroy the nesting habitat. It was to build a barrier. In 2012, crews installed 4,000 linear feet of black plastic irrigation tubing along the edge of Runway 4L, high enough that a terrapin cannot climb over it. The barrier reduced runway incursions by roughly 45 percent in its first year. Terrapins that breached it were collected by hand, scanned for microchip transponders, marked with nail polish and shell notches, injected with PIT tags if they were new, measured, weighed, aged, and released back into Jamaica Bay. By 2016, the Port Authority had processed 2,266 individual terrapins through the program.
Francoeur said the airport never could have predicted this. The original planners never imagined that all the sandy fill they put down would one day become the perfect nesting habitat for terrapins. She added that the turtles may prefer the airport specifically because the perimeter fencing keeps out the predators that would eat their eggs anywhere else in Jamaica Bay. The airport is, from a terrapin's perspective, a predator-free beach.
Diamondback terrapins have been nesting in Jamaica Bay since at least the late 1800s, when they were harvested commercially for turtle soup served in New York City restaurants. The population crashed under that harvest pressure and has been rebuilding ever since. The turtles nesting at JFK are younger on average than those nesting at the adjacent wildlife refuge, which suggests that the airport population is still growing, still recruiting new females, still choosing Runway 4L over the marshes their grandmothers used.
Image is for illustration purposes only
Source: U.S. Fish and Wildlife Service / Port Authority of New York and New Jersey / CBS News / AP / Untapped New York.
