Researchers have identified new feeding grounds for the endangered leatherback sea turtles along the central parts of the U.S. East Coast. Before this discovery, scientists were unsure of where these turtles traveled between their feeding grounds in the waters off Nova Scotia and New England in the summer and their breeding grounds off the Mid- and South Atlantic Bights in the colder months. Now, NOAA Fisheries researchers have found that the leatherbacks travel through locations like Cape Hatteras in North Carolina and Delaware Bay, where they feed, according to a study in the journal Frontiers in Marine Science.
Leatherback turtles are the largest species of sea turtles, measuring 5-6 feet long and weighing 750-1,000 pounds. They are primarily jellyfish eaters but may also consume other soft-bodied marine organisms, descending to depths of over 3,000 feet to hunt for food. Listed as “vulnerable” on the International Union for Conservation of Nature (IUCN) Red List, leatherback turtles are protected under the Endangered Species Act in the U.S. Their populations have declined by about 40 percent over the past three generations. They are known to migrate between the South Atlantic Bight and the Mid-Atlantic Bight up to the northern waters to feed during the summer and then south again during the winter months.
NOAA Fisheries researchers, along with others, tracked 52 leatherbacks using satellite tags off the coasts of Massachusetts and North Carolina. The tags provided information on the turtles’ diving depths and durations, indicating whether they were feeding or not. The turtles were observed to be engaging in feeding behavior off the coast of New England during late summer. Surprisingly, they were also found to be feeding much further south than expected, in Delaware Bay and Barnegat Bay in New Jersey, in the waters of the Mid-Atlantic Bight. This suggests that the Mid- and South Atlantic Bights are vital foraging areas for the turtles during their migrations, not just for breeding purposes.
Researchers were surprised to find that some male turtles deviated from their expected migration patterns, opting not to head towards the breeding grounds every year. This discovery challenges previous assumptions about male leatherback behavior and will impact estimations of adult sex ratios and population dynamics for each nesting population. The research findings will help scientists understand how changes in climate could impact these endangered turtles. The researchers aim to gather more data about the threats facing the turtles and plan to attach cameras to the turtles for further study, potentially shedding light on their daily lives and behaviors.
The discovery of new feeding grounds for leatherback sea turtles along the central U.S. East Coast has provided valuable insights into their migration patterns and behaviors. By tracking these endangered turtles using satellite tags, researchers have uncovered important information about their movements and foraging habits, highlighting the significance of the Mid- and South Atlantic Bights as crucial areas for these turtles during their migrations. This research not only contributes to our understanding of leatherback turtles but also has implications for conservation efforts and population dynamics modeling for these vulnerable species.
