Grant: 20-024R
Project Title: Green turtle health, biotoxin exposure, and foraging ecology in Lake Worth Lagoon, Florida
Project Manager: Dr. Annie Page-Karjian
Organization: Florida Atlantic University (Research and Educational Institute)
Grant Amount: $23,470.00
Completion Date: 2021-06-01

Summary: A major threat to Florida's ecosystems and wildlife health is the occurrence of harmful algal and/or cyanobacterial blooms (HABs), which are increasing in frequency, duration, and range, particularly in Florida. Biotoxins released during HABs can lead to lethal and sublethal consequences, such as decreased immune function, that affect the health and survival of organisms at multiple trophic levels. These effects can be especially detrimental to endangered species such as sea turtles and are important when considering life-histories and population viability analyses. To better understand the correlations between ecosystem health, diet, and health status in sea turtles, and how these may link to the effects of biotoxin exposure in juvenile green turtles foraging in Lake Worth Lagoon (LWL), Florida, we will complete the following objectives: (1): conduct collect health data and biological samples from juvenile green turtles captured in LWL during 2020–2021 (in collaboration with Inwater Research Group [IRG] and Palm Beach County Environmental Resources Management [PBC-ERM]), including evaluating infectious disease status and immune function, and identifying forage items via esophageal lavage; (2): document HAB-associated biotoxins in blood and diet; (3): statistically evaluate the relationships between health analytes, biotoxins, and diet; and (4): compare resulting data to data collected in ongoing surveys in other regions of Florida. The proposed research represents the addition of a sampling site and up to 25 more turtles to an ongoing, multi-site study being currently conducted by the PI and collaborators. The over-arching goal of the study is to generate critically needed data on the complex interplay between green turtle foraging ecology, biotoxin exposure, and health in this endangered species.

Results: Data on sample analysis results were received from collaborating institutions. From collaborators at the University of Connecticut, we have received the results of assessing esophageal lavage samples for a suite of 10 harmful algal bloom-related biotoxins using mass spectrometry, as well as immune function data derived from analysis of fresh whole blood samples. From the University of Georgia Infectious Diseases Lab, we have received results of qPCR for ChHV6 DNA and serology for antibodies to ChHV5 and ChHV6. We have also analyzed whole blood samples for ChHV5 DNA using qPCR in the Page-Karjian Lab at FAU. From University of Miami Avian & Wildlife Laboratory, we have received plasma protein electrophoretograms. From East Coast Biologists, Inc., we have received complete data sets on identification and categorization of esophageal lavage contents. All data collected for this project have now been collated, analyzed, and incorporated into a larger data set which includes health and biotoxin data for juvenile green turtles captured at five locations around Florida. A manuscript detailing the results of these surveys and analysis, including the samples analyzed using STC funds described here, is currently in preparation and is expected to be completed by December 2021, for submission to a relevant scientific journal. The project funded here constitutes one chapter of a Master’s thesis currently being completed by FAU graduate student Hunter Brown, who is in the FAU Master's in Marine Science and Oceanography Program and is a member of the Page-Karjian Lab.