About 150 turtles inching their way across a runway at New York's Kennedy International Airport reduced some flights to a crawl this morning.
The Federal Aviation Administration said delays reached 30 minutes for some flights.
FAA spokeswoman Arlene Salac said that the turtle procession started at 7:30 a.m. ET across Runway 4L. The runway was shut down at 9:30 a.m. when "the bulk of turtles started to go across."
Saac said that most of the flight delays were caused by changes in configuration as aircrafts lined up at alternate runways.
JetBlue acknowledged some delays with its flights because of the turtles and said, "We hope for faster animals next time."
The airline was quick to joke about the delays, tweeting around 10 a.m. that the creatures were diamondback terrapins, adding: "Though… there are rumors some of the turtles are of the ninja variety/subspecies."
According to ABC News' New York affiliate WABC, the turtles were trying to reach sand along the other side of Runway 4L, which juts out into the water. Workers from Port Authority of New York and New Jersey picked up the animals and moved them to the sand.
Turtles Tie Up Air Traffic at Kennedy Airport
"Our staff and the USDA were out there helping to speed the turtles along to their destination which is to lay eggs on a sandy, beachy area on the other side of the runway," Port Authority spokesperson Ron Marisco told ABC Radio.
According to Marisco, the turtles started crawling across the runway about two weeks ago. There could be further delays because the turtles are expected to continue their egg laying trek throughout July.
"It's kind of an annual event and our staff takes precautions to make sure the turtles get safely across the runways and taxiways and that the flights are not delayed too much," he said.
Salac said that the FAA cannot predict if future turtle behavior will cause flight delays this summer, but that "we would deal with situation the same way we dealt with it today."
The FAA database indicates that jets hit turtles a few times each year at JFK Airport, usually in the final days of June or earliest days in July.
The same type of turtle invasion occurred at the JFK airport in July 2009. Dozens of turtles shut down the runway for 35 minutes that year, causing 90 minute delays before nearly 80 turtles were removed from the tarmac.