Scientific Article

First Report of Metallic Elements in Loggerhead and Leatherback Turtle Eggs from the Indian Ocean

Bio-monitoring of pollutants in long-lived animals such as sea turtles is an important tool in ecotoxicology. We present the first report on metallic elements in sea turtle eggs from the Indian Ocean. Eggs of the leatherback and loggerhead turtle that breed on the Indian Ocean coast of South Africa were analysed for 30 elements. The eggshells and egg contents of the loggerhead turtle, the smaller of the two species, had higher or significantly higher concentrations than leatherbacks, except for strontium - the reason is unknown.

13 September 2018

Metals in Blood and Eggs of Green Sea Turtles (Chelonia mydas) from Nesting Colonies of the Northern Coast of the Sea of Oman

The green sea turtle (Chelonia mydas) has been a species of global concern for decades. In this study, heavy metals (mercury: Hg; Cadmium: Cd; Lead: Pb; Copper: Cu; and Zinc: Zn) were measured in blood and three egg fraction of green sea turtles nesting on the northern coast of Sea of Oman. Heavy metals concentrations in blood, yolk, albumen, and egg shell ranged between 0.16–36.78, 0.006–33.88, 0.003–4.02, and 0.002–6.85 μg/g (ww), respectively.

14 September 2018

A Global Review of Marine Turtle Entanglement in Anthropogenic Debris: a Baseline for Further Action

Entanglement in anthropogenic debris poses a threat to marine wildlife. Although this is recognised as a cause of marine turtle mortality, there remain quantitative knowledge gaps on entanglement rates and population implications. We provide a global summary of this issue in this taxon using a mixed methods approach, including a literature review and expert opinions from conservation scientists and practitioners worldwide.

14 September 2018

Growth Rates of Adult Sea Turtles

Indeterminate growth, i.e. growth that persists throughout life, is common in long-lived reptiles. Because fecundity and body size tend to be correlated in such species, individuals face a life-history trade-off at sexual maturity. Saturation tagging and intensive monitoring at nesting grounds can potentially provide opportunities to accumulate data on individual measurements and reproductive output.

17 September 2018

Public Awareness Program and Development of Education Toolkit for Green Sea Turtle Conservation in Sarawak, Malaysia

Nobody knows exactly what happened during "the lost years" of the turtles in the wild, thus a green turtle headstarting project was carried out at Pantai Pandan, Lundu, Sarawak, Malaysia from June 2014 until December 2015 to shed some lights on the growth of hatchlings during a small part of their "lost years". As a consequent, opportunity of small scale awareness campaigns on sea turtle conservation arises during this project. Activities include talk related to green turtles conservation, hands on experience on turtle-human interaction (supervised), and documentation via videography.

14 September 2018

Genetic Diversity of the Green Turtle (Testudines: Cheloniidae: Chelonia mydas (Linnaeus, 1758)) Population Nesting at Kosgoda Rookery, Sri Lanka

We determined the genetic diversity of the Green Turtle Chelonia mydas (Linneaus, 1758) nesting at Kosgoda rookery, the second largest sea turtle aggregation on the southwestern coast of Sri Lanka. Skin tissue samples were collected from 68 nesting females and genetic diversity was estimated using six microsatellite loci. High genetic diversity was observed within the population as all loci analyzed were highly polymorphic with a total of 149 alleles observed.

13 September 2018

Eretmochelys imbricata: Lessons to Learn from a Monitoring Program in the North of Mozambique

Monitoring programs for nesting turtles around the world have been important to build up a matrix of information for better comprehension of their behaviour and dispersion. The Western Indian Ocean has several monitoring programs that are being used to reveal migration routes, phylogenetic interconnections and nesting behaviour patterns. We determined the nesting parameters for 69 records of hawksbill turtles collected during the Vamizi Island monitoring program.

13 September 2018

A 20-year Investigation of Declining Leatherback Hatching Success: Implications of Climate Variation

Unprecedented increases in air temperature and erratic precipitation patterns are predicted throughout the twenty-first century as a result of climate change. A recent global analysis of leatherback turtle hatchling output predicts that the nesting site at Sandy Point National Wildlife Refuge (SPNWR) will experience the most significant regional climate alterations. We aimed to identify how local air temperatures and precipitation patterns influenced within-nest mortality and overall hatchling output at this site between 1990 and 2010.

13 September 2018

Using Photographic Identification To Monitor Sea Turtle Populations At Perhentian Islands Marine Park In Malaysia

Perhentian Islands Marine Park is home to foraging and nesting Green Turtles (Chelonia mydas) and Hawksbill Turtles (Eretmochelys imbricata) but little information is available other than nesting trends and hatching success. We used photographic identification (photo-ID) methods to identify individuals and to determine their sex ratios, habitat use, and site fidelity.

14 September 2018

Comparing Acoustic Tag Attachments Designed for Mobile Tracking of Hatchling Sea Turtles

The poorly understood movements of sea turtles during the “lost years” of their early life history have been characterized as a “passive drifter” stage. Biologging technology allows us to study patterns of dispersal, but the small body size of young life stages requires particular consideration that such tagging does not significantly impede animal movements. We tested the effect of instrument attachment methods for mobile acoustic tracking of hatchling sea turtles, including a design that would be suitable for leatherback turtles (Dermochelys coriacea).

13 September 2018