Sea Turtles

Sargassum also plays an important role in the life cycles of many marine animals, one example is the Sea Turtle. Turtle hatchlings use Sargassum mats as a floating refuge from predators. While floating Sargassum provides habitat for hatchlings, decomposing Sargassum covering nests may pose a threat. Sargassum often co-occurs during sea turtle nesting leaving the opportunity to harm eggs and hatchlings. New questions have arose of heavy metal leeching in relationship to substantial Sargassum landings. Testing sea turtles, their eggs, yolks, and hatchlings for heavy metals is not a novel idea, nor is testing pelagic Sargassum for these same metals. As recent as 2019, heavy metal levels in Sargassum were found to be high. While there is tolerance of heavy metal in sea turtles, they could potentially reach beyond a safe threshold.

We collect samples of Sargassum for nutrient content, (CNP), and heavy metals such as Arsenic. South Florida’s geographical position and seasonality that co-occurs with sea turtle nesting season provide a unique opportunity to study these impacts. Currently, clean-up procedures are geared towards populated and tourist-heavy beaches, but it might be beneficial to extend clean-up efforts to all nesting beaches. We need to know whether the removal of exceptionally large mounds of Sargassum is necessary to protect nests, or if leaving the mounds results in minimal harm.

In the Spring of 2020, our undergraduate student Samantha Olszak received a scholarship from the National Save the Sea Turtle Foundation. This has allowed for continued research and testing of the three main pelagic Sargassum morphotypes we experience here in South Florida.

Parr, A. E. (1939). Quantitative Observations on the Pelagic Sargassum Vegetation of the Western North Atlantic: With Preliminary Discussion of Morphology and Relationships. Millwood, NY: Kraus Reprint.

Wrinn, C., Schell, J., Goodwin, D., & Suida, A. (2016). Taxonomic Guide to Pelagic Sargassum in the Caribbean and North Atlantic Ocean. Proceedings of 69th Annual Gulf and Caribbean Fisheries