Gastrointestinal Parasites and Food Intake of Stranded Juvenile Green Turtles Chelonia mydas (Testudines: Cheloniidae) in Rio de Janeiro, Brazil


  • Rodrigo Mariath Varela da Costa Universidade Santa Úrsula, 75 Fernando Ferrari Str. - Botafogo, Rio de Janeiro, RJ, Brazil
  • Débora Afonso Silva Rocha Universidade Santa Úrsula, 75 Fernando Ferrari Str. - Botafogo, Rio de Janeiro, RJ, Brazil
  • Natalie Villar Freret-Meurer Animal Behavior and Conservation Laboratory. Universidade Santa Úrsula, 75 Fernando Ferrari Str. - Botafogo, Rio de Janeiro, RJ, Brazil


parasites, infection, diet shift, sea turtle, Atlantic ocean


Chelonia mydas can be found worldwide, mainly in coastal habitats ranging from tropical regions to temperate zones. They usually consume a diverse range of food types, however, adults are considered one of the most abundant large vertebrate consumers of seagrasses and algae in the world. Anthropogenic activities can affect C. mydas morbidity, mortality and food intake pattern. The aim of this study was to  evaluate if parasites can interfere with the food intake of green turtles in Rio de Janeiro, Brazil, after gastrointestinal content and parasitological analysis. A total of 137 stranded green sea turtles were analyzed, according to the presence of parasites and the digestive tract content: 12% presented parasite infection. The most frequent item among the digestive tract content was algae (74%), followed by anthropogenic materials (19.8%), invertebrates (5.8%) and plants (0.4%). The algae mostly ingested were the Chlorophyta with 36,16% and Rhodophyta with 27,68%. Phaeophyta represented 14,69% of the consumed algae, 20,9% of the algae could not be identified due to the digestive process. Thus, in this study  we could observe a change in species composition and algal frequency in green turtles with or without parasites. Hypnea sp. is frequently reported in the literature as part of the diet of C. mydas and, the same was observed in our results in non-parasitized green turtles. More studies are necessary to better understand anthropogenic debris and parasites infection effects on food intake of  stranded juvenile green turtles Chelonia mydas.


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How to Cite

Rodrigo Mariath Varela da Costa, Afonso Silva Rocha , D., & Natalie Villar Freret-Meurer. (2023). Gastrointestinal Parasites and Food Intake of Stranded Juvenile Green Turtles Chelonia mydas (Testudines: Cheloniidae) in Rio de Janeiro, Brazil. International Journal of Natural Sciences: Current and Future Research Trends, 17(1), 20–30. Retrieved from