Marine Iconic Species Ecology and Conservation
Large marine vertebrates have some traits in common, such as late age at maturity, low reproductive rates and be long-living, that make them highly vulnerable to negative effects of human activities. Iconic species such as sharks, sea turtles, dolphins and whales, offer a unique opportunity for conservation because they often evoke emotional responses from the public, are valued traditionally and culturally, and may have an umbrella effect on other less popular species.
Sea turtles living in the Pacific Islands are threatened of extinction and their decreasing populations’ size call for immediate conservation actions, however their complex life cycle, with different life stages exploiting different habitats and resources, highly migratory behavior, fidelity to multiple foraging grounds, cyclic but non-annual breeding, philopatry to their natal region, and temperature-dependent sex-determination, make their management and protection extremely complex.
At the School of Marine Studies we are working to discover the ecology of sea turtles to provide a solid, scientific background on which management can be based to achieve the species recovery, through a research program that is interdisciplinary and applied.
Projects:
Conservation of American Samoa-origin stock of green turtles in a key foraging ground in Fiji, with cascade effects on management of central South Pacific sea turtle populations (2015-2017).
Principal Investigator: Dr Susanna Piovano
Fiji seagrasses and algae play a fundamental role as foraging grounds for green turtles in the entire central South Pacific, and a clear linkage between American Samoa green turtles population and the foraging grounds of Fiji was proven by both satellite and flipper-tagging programs. Results from the same programs also showed a high mortality encountered by green turtles when in Fijian waters: 38% of the American Samoa nesting females for which a migration to Fiji has been recorded, were captured in Fiji for local consumption. The capture of sea turtles in Fiji is managed since 1942. Beginning in 1995, sea turtles have been granted protected status through three almost consecutive Moratorium included the current one, which will remain effective until 2018. However, harvest is ongoing in several communities, to the point that the efficacy of the Moratorium in protecting sea turtles has been questioned. Project goal is the evaluation of the American Samoa green turtle population foraging ecology and habitat use of a key Fijian foraging ground during nesting and non-nesting season, which will be reached by applying a multidisciplinary approach.
Genetic stock assessment of sea turtles nesting populations in Fiji (2014-2017)
Principal Investigator: Dr Susanna Piovano
Sea turtles are long-lived reptiles with a complex life cycle and highly migratory habits. Many populations are facing decline worldwide, and all but one species, for which information are lacking, are currently listed as threatened on the IUCN Red List. The Fiji islands host nests for hawksbill and green turtles. A sharp decrease in the number of nests has been reported for both species since 1970 and, until now, no sign of recovery has been noticed. There is a growing literature on unilateral conservation efforts which shown that these have been insufficient for the recovery of sea turtles populations. In the case of Fiji, the lack of genetic characterization of local nesting populations prevents the identification of turtles from Fijian rookeries when captured abroad. There is a compelling need for the genetic assessment of Fiji sea turtles nesting populations in order to effectively plan management and conservation activities. The primary aims of this project are 1) to characterize genetic signatures of Fiji’s rookeries and determine levels of stock structure among rookeries in Fiji, and 2) to provide rookery baseline data for Fiji to enable stock ID of Fiji-origin turtles at foraging grounds and fishery bycatch as part of ongoing Pacific-wide effort being carried out by multiple research institutions.
News: 18-23 February 2018: Dr Susanna Piovano and Ms Shritika Prakash attended the 38th International Sea Turtle Symposium in Kobe, Japan
Masters thesis:
- Shritika Shayal Prakash (s11086721@usp.ac.fj): Nests distribution and paternal contribution to hawksbill nests in Fiji
- Henry Vavu Kaniki (s11035156@usp.ac.fj): Climate proofing sea level rise and nesting hawksbill turtle at Arnavon Islands, Solomon Islands
Mini thesis:
- Arvindra Rishi Prasad (s11042903@usp.ac.fj): Capture and consumption of sea turtles in the Manning Strait, Solomon Islands (completed in 2017)