Using advanced tracking technology, U.S. researchers have discovered new migratory corridors and feeding areas for leatherback sea turtles along the U.S. East Coast, specifically in the South Atlantic Bight, Mid-Atlantic Bight, and southern New England. The findings, published in Frontiers in Marine Science, highlight important feeding areas and have important implications for the conservation of this endangered species, especially in the face of threats from fisheries and offshore wind farm development.
Leatherback turtles are the largest of the living sea turtles and they undergo massive migrations that can last for several years. These turtles migrate from warm subtropical and tropical nesting grounds to cooler temperate areas to feed. Even after years of tracking, there are still gaps in knowledge, particularly regarding their migration paths and feeding grounds in certain areas, such as the northwest Atlantic.
A U.S. research team has used new, more advanced tracking technology to identify migration corridors and potential feeding areas for leatherback turtles along the U.S. East Coast. The research results were published in Frontiers in Marine Science.
"Using mobile behavior modeling, we found that leatherback turtles migrating along the U.S. East Coast exhibit inferred foraging behavior in specific areas of the South Atlantic Bight (SAB) (the coastal area from North Carolina to the upper Florida Keys), the Mid-Atlantic Bight (MAB) (the coastal area from Massachusetts to North Carolina), and Southern New England (SNE)," said Dr. Mitchell Rider, a postdoctoral researcher at the University of Miami. "It appears that the MAB may be an important feeding site for leatherback turtles."
Discover new feeding spots
To track the turtles, researchers attached satellite transmitters to two groups of leatherbacks. The first group tagged in the summer off Massachusetts, and the second group tagged in the spring off North Carolina.
Near Massachusetts is a known feeding area from which leatherback turtles migrate north after feeding. Tracking them there allowed researchers to identify secondary feeding and overwintering areas along the continental shelf. By tracking sea turtles captured near North Carolina, researchers are able to assess diving and movement behavior along migratory routes and identify subsequent foraging areas. Between 2017 and 2022, 52 leatherback turtles were successfully tracked, with tracking periods ranging from 15 to 302 days.
The researchers' findings indicate that in addition to their known feeding areas in New South Wales and Nova Scotia, leatherback turtles use the New South Wales, MAB and Nova Scotia MAB regions as migration corridors and feeding areas. "The heavy use of man and biosphere by both groups of leatherback turtles is the most important finding of our study. The main characteristic of high use is inferred foraging behavior," said Rider. "Several studies have so far tracked leatherback turtles entering this area, but ours is the first to go a step further and describe the behavior associated with their movement patterns."
protect knowledge
New insights into the foraging areas and movement ecology of leatherback turtles on the northwest Atlantic shelf are likely to open new doors for future work studying leatherback turtles in the MAB and South Atlantic Biosphere, the researchers say. "Now that we understand the main hotspots of foraging, we need to focus our attention on these specific areas by using methods that enable direct observation. To do this, we need to implement more field research methods, such as animal-borne video surveillance," Reed explained.
Researchers say that although they now have a better understanding of the leatherback's movements and foraging, there is still much work to be done. This includes studying leatherback turtle movements in South Atlantic waters, as this area appears to be where leatherbacks overwinter, nest in the spring, and forage in the summer.
The researchers say their findings could also be important for protecting endangered species. Leatherback turtles are easily caught accidentally or struck by fishing boats. The new findings could be used to highlight key areas for protection and help prevent these accidents from happening. Additionally, MAB and southern New England will see significant offshore wind farm development, and conservationists can use this knowledge to help mitigate impacts to endangered sea turtles.
Compiled source: ScitechDaily