Turtle history: leatherback migrations (Introduction)

by David Turell , Saturday, March 16, 2024, 18:23 (42 days ago) @ David Turell

A new study:

https://www.sciencedaily.com/releases/2024/03/240315160342.htm

"The waters off Cape Cod and Nantucket promote a high abundance of jellyfish in the late summer and early fall, which the leatherbacks appear to be taking advantage of. The scientists observed some of the leatherbacks tagged along Nantucket Shoals, stayed in the area for weeks to months after tagging before migrating back south.

"In the Mid-Atlantic Bight, the team inferred that there is food availability, given the high number of leatherbacks that displayed feeding-like behavior year after year. However, the team noted the lack of research on prey distributions in this area, and further observations for leatherbacks would benefit by returning to the site to deploy camera tags to determine what the leatherbacks are feeding on.

"The South Atlantic Bight appears to support several stages of the migration cycle: nesting, post-nesting foraging, and overwintering. Not as many leatherbacks frequented this area, but the ones that were tracked displayed feeding-like behavior especially along the continental shelf ridge. Previous research in the area indicates that blooms of cannonball jellyfish occur nearshore in the South Atlantic Bight primarily during the spring, which coincides with leatherbacks overwintering and nesting stages of their migration cycle.

"Our study revealed a significantly higher utilization of the U.S. coastline by leatherbacks, particularly along regions of the Mid-Atlantic Bight, South Atlantic Bight, and Southern New England. These areas emerged as possible major foraging grounds for leatherbacks migrating along the United States coastline, with notable activity observed off the coast of North Carolina.

"'A key finding was further defining the Mid-Atlantic Bight as a critical foraging ground for leatherbacks from past studies, identified through sophisticated behavioral analysis," said Rider. "By incorporating diving metrics such as dive frequency and duration, the study provides a comprehensive understanding of leatherback behaviors that distinguishes between their migration and foraging activities."

"Furthermore, the study highlighted the vulnerability of leatherbacks to incidental capture by fisheries and vessel strikes, underscoring the urgent need for conservation efforts to mitigate these risks. With impending developments, particularly the construction of offshore wind farms in the Mid-Atlantic Bight and Southern New England regions, the findings serve as a relevant guide for conservation managers to minimize impacts on this endangered species."

Comment: Along the Texas coast large numbers of eggs are left to incubate and must be protected, as elsewhere along the coast.