Pratt 1 Thomas Pratt Marine Conservation and Policy Title : The Riverhead Foundation: Using necropsies to increase awareness of marine conservation issues. Sea turtle biology Sea turtles have been around for more than 100 million years (Lutz et al. 2002). Today, there are seven species of sea turtles in existence which includes green sea turtles (Chelonia mydas), loggerhead sea turtles (Caretta caretta), leatherback sea turtles (Dermochelys coriacea), olive ridley sea turtles (Lepidochelys olivacea), kemp’s ridley sea turtles (Lepidochelys kempii), flatback sea turtles (Natador depressus) and hawksbill sea turtles (Eretmochelys imbracata). There is a myriad of of different things that sea turtles eat. Every sea turtle species is different, and has its own unique diet. Leatherback sea turtles predominantly consume gelatinous plankton such as jellyfish and even salps, while green sea turtles are herbivores and eat a diet of mostly seagrass and algae that even changes their adipose tissue slightly green (Bjorndal 1997, Mrosovsky et al. 2009). Loggerhead sea turtles have a varied diet depending on their life stage, and tend to eat prey items such as crustaceans, gastropods, sargassum, jellyfish, and even terrestrial insects (Bjorndal 1997). In New York State, species of sea turtles that are found include green sea turtles (Chelonia mydas), loggerhead sea turtles (Caretta caretta), leatherback sea turtles (Dermochelys coriacea) and kemp’s ridley sea turtles (Lepidochelys kempii). Many sea turtle diets depend upon their movements and habitat that they are in. Hawksbill sea turtles (Eretmochelys imbracata) are often pelagic species, yet tend to migrate towards the shore to forage off of coral reefs and mangroves (Bjorndal 1997). Hawksbill sea
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Pratt 1
Thomas Pratt
Marine Conservation and Policy
Title: The Riverhead Foundation: Using necropsies to increase awareness of marine conservation
issues.
Sea turtle biology
Sea turtles have been around for more than 100 million years (Lutz et al. 2002). Today,
there are seven species of sea turtles in existence which includes green sea turtles (Chelonia
Specialist Group 1996, Mortimer and Donnelly 2008). Since these species are particularly
endangered, threats such as fisheries and human impact can become a distinct problem for their
future populations.
Current and future research is essential for awareness of these endangered species. Every
year, more scientific research is being conducted about sea turtles, including research done by
The Riverhead Foundation. Every year the Riverhead Foundation comprises annual reports about
cetaceans, pinnipeds and sea turtles. In the reports include all of the sea turtle strandings in the
New York State area, which dates back to 1980. In the chart below represents sea turtle
strandings by species from 1980 up to last year. Since 2007, sea turtle strandings have increased
slightly, and the majority of sea turtles that are found are Loggerhead and Kemp’s ridley sea
turtles (DiGiovanni Jr. et al. 2013). By observing the amount of sea turtle strandings and the sex
of sea turtles from the past and years to follow, the threat of climate change can be evaluated.
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This scientific data done by the Riverhead Foundation is published annually and used in lectures
and events to help increase awareness through education.
(DiGiovanni Jr. et al. 2013)
With regards to other research being done, there are many issues being addressed such as
bycatch records, sea turtle diet, nesting habitat, and marine pollution and debris. Bycatch
research is being done through Duke Marine Laboratory and Blue Ocean Institute through Stony
Brook University (Lewison et al. 2014). Certain bycatch hotspots for many marine megafauna
such as sea turtles have been identified, and can assist in bycatch management from gear type
and migration routes (Lewison et al. 2014). Species such as loggerhead and leatherback sea
turtles are threatened due to pelagic longlines and fisheries bycatch, therefore studied like this is
important for the future of sea turtles.
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There is a variety of research being done on sea turtle diet and habitat. One current study
uses stable isotope analysis through the use of scute and epidermis samples (Vander Zanden et
al. 2014). This study is using stable isotope analysis to determine the habitat and diet of sea
turtles through isotopic composition (Vander Zanden et al. 2014). It is possible through current
research like this, to help determine migration routes of loggerhead sea turtles through diet and
habitat use (Vander Zanden et al. 2014). By knowing what and where a sea turtle forages, we
will know what marine areas to manage and protect.
Other current research includes analysis of marine debris ingested such as plastic debris.
Presentday research has shown that out of the seven species of sea turtles, leatherback
(Dermochelys coriacea) and green (Chelonia mydas) sea turtles are the species that ingest the
most marine debris (Schuyler et al. 2014). Since green sea turtles are herbivores and leatherback
sea turtles are gelatinous planktivores, marine debris poses a considerable risk to these species
(Schuyler et al. 2014). By knowing what marine debris is often found ingested in these animals
through necropsies, we will know what kinds of pollutants such as plastic to regulate. Since sea
turtles are highly migratory, pelagic species, the majority of research that has been done is recent
due to the establishment of modernday technologies. The future of sea turtles may rely on the
current conservation research being done, and the action to counteract the effect of human
impact is just as crucial. The current research on sea turtles, including sea turtle strandings could
potentially help the management and conservation of future sea turtle populations.
References
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