Indian Ocean

A Piece of a Puzzle of Haplotypes for the Indian Ocean Hawksbill Turtle

The Indian Ocean basin has much to reveal in what concerns marine turtles. Its regional management units (RMUs) are still lacking molecular data to define conservation strategies and priorities. Vamizi Island is one of the best known rookeries in the north of the Mozambique Channel. A mitochondrial DNA analysis revealed 14 haplotypes for the hawksbill turtle’s nesting and foraging in/near Vamizi, twelve of which were new in 2011. Though more studies inside the Channel are needed, Vamizi Island possibly contributes with hatchlings for other locations.

13 September 2018

How Numbers of Nesting sea Turtles can be Overestimated by Nearly a Factor of Two

Estimating the absolute number of individuals in populations and their fecundity is central to understanding the ecosystem role of species and their population dynamics as well as allowing informed conservation management for endangered species. Estimates of abundance and fecundity are often difficult to obtain for rare or cryptic species.

14 September 2018

Spatial Distribution and Residency of Green and Loggerhead Sea Turtles Using Coastal Reef Habitats in Southern Mozambique

Sea turtles spend the majority of their immature and adult lives in foraging grounds, yet few studies have examined their abundance and condition in these areas when compared to more accessible nesting beach habitats. Here, a 5-year dive log, photo-identification (photo-ID) and surface encounter datasets were used to investigate the abundance, individual movements and distribution of sea turtles along 40 km of coastal reefs in southern Mozambique. A generalized linear model (GLM) was constructed with turtle sightings as the response variable.

07 September 2020

Integrating Over Sea Radio Channel for Sea Turtles Localization in the Indian Ocean

This paper deals with the modeling of over sea radio This paper deals with the modeling of over sea radio channel with the aim of establishing sea turtle off the coast of Reunion Island but also on Europa Island in the Mozambique Channel. In order to model this ratio channel, we are making a measurement protocol. In a first approach, measurements of turtle trajectory were done over land and finally it will be conducted over sea. We have scheduled an over sea measurement campaign in the middle of June.

15 July 2019

Low Genetic Diversity after a Bottleneck in a Population of a Critically Endangered Migratory Marine Turtle Species.

Hawksbill turtles (Eretmochelys imbricata), which are distributed throughout the world's oceans, have undergone drastic declines across their range, largely due to anthropogenic factors. Assessing sizes, genetic variability and structure of their populations at global and regional levels is critical to the development of conservation management strategies.

14 May 2019

Evaluating the Threat of IUU Fishing to Sea Turtles in the Indian Ocean and Southeast Asia using Expert Elicitation

Illegal, unreported and unregulated (IUU) fishing is a pervasive issue that affects economic, social, regulatory and environmental systems in all ocean basins. Research on the ecological impacts of IUU fishing has been relatively underrepresented, with minimal investigation into how IUU fishing may negatively affect populations of marine megafauna, such as sea turtles.

13 September 2018

A Comprehensive Survey of Pelagic Megafauna: Their Distribution, Densities, and Taxonomic Richness in the Tropical Southwest Indian Ocean

The distribution and density of pelagic megafauna (marine mammals, seabirds, elasmobranches, and sea turtles) are important indicators of marine biodiversity, reflecting the condition of the underlying ecosystems. A dedicated aerial survey was conducted in the tropical Southwest Indian Ocean to map their distribution, the taxonomic diversity, and to estimate their densities to serve as a baseline for the area.

14 September 2018

Citizen Science Surveys Elucidate Key Foraging and Nesting Habitat for two Endangered Marine Turtle Species within the Republic of Maldives

We used a citizen science-based data collection protocol to investigate foraging and nesting marine turtle populations in the Republic of Maldives. With the aid of citizen scientists, we collected nine months of data covering 12.5 % of the country, increasing the available sightings and nesting data by ~2,000 %. Data indicated that the Maldives are an important foraging habitat for juvenile and adult green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) turtles, though very few adult males of either species were reported.

13 September 2018

Monitoring of Nesting Sites of Olive Ridleys and Identification of Future Potential Mass Nesting sites Along the Gahirmatha Rookery, Odisha, East Coast of India

Sea turtles are known to occupy a series of different habitats in their lifetime which are broadly categorized into the terrestrial habitat of the nesting females and the pelagic and oceanic habitat of the immediate post-hatchling phase. However, the terrestrial habitat of the nesting females plays a very important role in the life cycle of the sea turtles as this is where the next generation is hatched. Female sea turtles need to come onto land to lay eggs for which they must have access to suitable beaches (Hendrickson 1982; Plotkin 2010; Behera et al. 2013).

15 July 2019

Beach Dynamics and Impact of Armouring on Olive Ridley Sea Turtle (Lepidochelys olivacea) Nesting at Gahirmatha Rookery of Odisha Coast, India

Gahirmatha arribada beach are most dynamic and eroding at a faster rate over the years from 2008-09 to 2010-11, especially during the turtles breeding seasons. Impact of armouring cement tetrapod on olive ridley sea turtle nesting beach at Gahirmatha rookery of Odisha coast has also been reported in this study. This study documented the area of nesting beach has reduced from 0.07 km2to 0.06 km2.

15 July 2019