scholarly journals The Recent Nesting Record of Female Green Turtle, Chelonia mydas, at Pamban, Gulf of Mannar

2014 ◽  
Vol 6 (4) ◽  
pp. 414-416
Author(s):  
Vellathi VENKATESAN ◽  
Chellapa KALIDAS
Keyword(s):  
Green Turtle ◽  
Monsoon Season ◽  
High Tide ◽  
Chelonia Mydas ◽  
Gulf Of Mannar ◽  
Important Place ◽  
Continuous Mixing ◽  
Nesting Site ◽  
Turtle Population ◽  
Egg Diameter

A female green turtle was sighted at Pamban along the Gulf of Mannar just after the nesting on the beach on 15th January 2011. Morphometric measurements of the turtle were taken and data suggests that this individual is adult. A total number of laid eggs were 109. The distance between the nesting site and the high tide line was found to be 7 m. The depth and diameter of the nesting pit was 52 and 16 cm, whereas the mean egg diameter and weight were found to be 44.3 mm and 40.5 g respectively. Pamban coast may also be considered an important place for nesting, because of the continuous mixing of waters of GOM and Palk Bay areas, which in turn create current patterns continuously throughout the year in addition to the monsoon season. Conservation of nesting habitat along Gulf of Mannar will be important to maintain the green turtle population.

Structural description of sea turtle fibropapilloma

2020 ◽  
Vol 13 (3) ◽  
pp. 585-591
Author(s):  
Luana Melo ◽  
Isabel Velasco ◽  
Julia Aquino ◽  
Rosangela Rodrigues ◽  
Edris Lopes ◽  
...  
Keyword(s):  
Green Turtle ◽  
Chelonia Mydas ◽  
Sea Turtle ◽  
Tumor Formation ◽  
Neoplastic Disease ◽  
Structural Description ◽  
Chemical Carcinogens ◽  
Epidermal Proliferation ◽  
Turtle Population ◽  
Bulky Mass

Fibropapillomatosis is a neoplastic disease that affects sea turtles. It is characterized by multiple papillomas, fibropapillomas and cutaneous and/or visceral fibromas. Although its etiology has not been fully elucidated, it is known that there is a strong involvement of an alpha - herpesvirus, but the influence of other factors such as parasites, genetics, chemical carcinogens, contaminants, immunosuppression and ultraviolet radiation may be important in the disease, being pointed out as one of the main causes of a reduction in the green turtle population. Thus, the objective of this article was to describe the morphology of cutaneous fibropapillomas found in specimens of the green turtle (Chelonia mydas), using light and scanning electron microscopy in order to contribute to the mechanism of tumor formation. Microscopically, it presented hyperplastic stromal proliferation and epidermal proliferation with hyperkeratosis. The bulky mass was coated with keratin, with some keratinocyte invaginations, that allowed the keratin to infiltrate from the epidermis into the dermis, forming large keratinized circular spirals. Another fact that we observed was the influence of the inflammation of the tumors caused by ectoparasites.

Using Animal-Borne Imaging to Assess Green Turtle (Chelonia mydas) Foraging Ecology in Moreton Bay, Australia

2007 ◽  
Vol 41 (4) ◽  
pp. 9-13 ◽  
Author(s):  
Karen E. Arthur ◽  
Judith M. O'Neil ◽  
Colin J. Limpus ◽  
Kyler Abernathy ◽  
Greg Marshall
Keyword(s):  
Feeding Ecology ◽  
Green Turtle ◽  
Foraging Ecology ◽  
Chelonia Mydas ◽  
Lyngbya Majuscula ◽  
Imaging Device ◽  
Green Turtles ◽  
Moreton Bay ◽  
Turtle Population ◽  
Insight Into

Traditional techniques for studying green turtle foraging ecology, such as the analysis of food availability and ingested dietary material, have concluded that green turtles are primarily herbivorous but selective foragers. However, green turtles that forage during Lyngbya majuscula blooms are exposed to toxins produced by the cyanobacterium overgrowing the seagrass. We used the Crittercam, an animal-borne imaging device, to observe green turtle foraging behavior in Moreton Bay, Australia, and to evaluate the system for assessing the impacts of Lyngbya blooms on green turtles. Eight large green turtles were captured while foraging on seagrass flats and each was fitted with a Crittercam. The deployments yielded over 28 hours of video and associated time-depth records. Turtles swam almost continuously and rarely stopped to feed on seagrass. Six turtles were observed feeding and all six consumed gelatinous animals from the water column. This prey source was previously undocumented in the Moreton Bay green turtle population but described in other green turtle populations using the Crittercam. Only one turtle was observed foraging on seagrass. The results of this study indicate that Crittercam technology can provide insight into turtle diet selection and that it will be a useful tool in identifying the impacts of Lyngbya blooms on green turtle feeding ecology. This study has also demonstrated that turtles in Moreton Bay may have a more flexible diet than previously described, indicating they could potentially supplement their diet with alternate prey items when seagrass quality or quantity is compromised. Longer deployment times, with an initial acclimation phase, are required to more fully understand questions pertaining to feeding ecology.

scholarly journals KARAKTERISTIK SARANG PENYU HIJAU (CHELONIA MYDAS) DI PULAU KASIAK KAWASAN KONSERVASI PENANGKARAN PENYU PARIAMAN, SUMATERA BARAT

2018 ◽  
Vol 46 (2) ◽  
pp. 42
Author(s):  
Desi Nova Sari ◽  
Muhammad Fauzi ◽  
Eni Sumiarsih
Keyword(s):  
Green Turtle ◽  
High Tide ◽  
Chelonia Mydas ◽  
Nest Temperature ◽  
Thespesia Populnea ◽  
Quality Of Water ◽  
Substrate Texture ◽  
Water Edge ◽  
The Common

The research aimed to understand the nesting area characteristic of C. mydas in the Kasiak Island was conducted from March-April 2017, coincidence with the nesting time of green turtle. Observation of the nesting area of green turtle was conducted in the Northern, Southern, Western and Eastern parts of the island. Parameters studied were the slope of the beach, the distance between the water edge during the high tide and the nest, sand texture, types of vegetations around the nest, number of nests present and the quality of water around the island.  Results shown that the coast’s slope ranged from 1.74 to 2.890, the distance between the water edge during the high tide and the nest ranged from 1.17 to 1.70 m, the substrate texture was dominated by sand (> 90%), silt (3.4-7.25%) and clay (2-8%).  The nest temperature was 25-320C, nest humidity was 30-40% and the common vegetation was Thespesia populnea.  Quality of the water  around the Kasiak Island are as follows: temperature was 29-300C, salinity was from 33-34 ‰, current speedwas 0.4-0.5 m / s and pH was 8.

scholarly journals Genetic diversity of the Green Turtle (Testudines: Cheloniidae: Chelonia mydas (Linnaeus, 1758)) population nesting at Kosgoda Rookery, Sri Lanka

2017 ◽  
Vol 9 (6) ◽  
pp. 10261
Author(s):  
E. M.L. Ekanayake ◽  
T. Kapurusinghe ◽  
M. M. Saman ◽  
D. S. Rathnakumara ◽  
P. Samaraweera ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Sri Lanka ◽  
Green Turtle ◽  
Chelonia Mydas ◽  
Sea Turtle ◽  
High Genetic Diversity ◽  
Tissue Samples ◽  
Hardy Weinberg Equilibrium ◽  
Turtle Population ◽  
The Mean

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.  The mean number of alleles per locus was 24.7 and the mean observed and expected heterozygosity across all loci were 0.75 and 0.93, respectively.  It appears that five out of six loci were not in Hardy-Weinberg equilibrium, while micro-checker analysis suggested that the Kosgoda Green Turtle population was possibly in equilibrium.  The viability of a population is unlikely to be reduced if high genetic diversity is maintained within it.  Although the Green Turtle population nesting at Kosgoda is small compared to other nesting rookeries in the world, the high genetic diversity observed suggests that the population may not be undergoing a bottleneck.

Low male production at the world’s largest green turtle rookery

2020 ◽  
Vol 653 ◽  
pp. 181-190
Author(s):  
DT Booth ◽  
A Dunstan ◽  
I Bell ◽  
R Reina ◽  
J Tedeschi
Keyword(s):  
Green Turtle ◽  
Hatching Success ◽  
Incubation Temperature ◽  
Chelonia Mydas ◽  
Sea Turtle ◽  
Green Turtles ◽  
Nesting Site ◽  
Almost All ◽  
Monthly Variations ◽  
Nesting Season

Because the sex of all sea turtle hatchlings is determined by incubation temperature, with low temperatures producing mainly males and high temperatures producing mainly females, sea turtle populations worldwide are threatened by feminization of hatchlings due to increases in global temperature. Data obtained by laparoscopic sexing of immature individuals captured from a major feeding ground indicates that over several decades there has been little recruitment of males into the northern Great Barrier Reef (nGBR) green turtle Chelonia mydas population, one of the largest sea turtle populations in the world. Over 2 nesting seasons, we measured nest temperatures at Raine Island, the most important nesting site for this nGBR population, and predicted that almost all nests would have produced all female hatchlings. The few nests that produced some male hatchlings were constructed at the very end of the nesting season, and these nests had the lowest hatching success. Taking into account monthly variations in nest construction, hatching success, and hatchling sex ratio, we estimate that over an entire nesting season only 0.7% of hatchlings produced are male. Hence, we conclude that the nGBR population of green turtles has likely recruited very few males in recent years.

scholarly journals KONDISI HABITAT DAN KAITANNYA DENGAN JUMLAH PENYU HIJAU (Chelonia mydas) YANG BERSARANG DI PULAU DERAWAN, BERAU-KALIMANTAN TIMUR

2017 ◽  
Vol 14 (2) ◽  
pp. 195
Author(s):  
Dharmadi Dharmadi ◽  
Ngurah Nyoman Wiadnyana
Keyword(s):  
Green Turtle ◽  
Habitat Degradation ◽  
Survey Methods ◽  
High Tide ◽  
Chelonia Mydas ◽  
Sea Turtle ◽  
Coastal Vegetation ◽  
Vegetation Density ◽  
Nesting Habitat ◽  
East Kalimantan

Chelonia mydas merupakan spesies penyu yang paling umum dari 6 spesies yang ditemukan di Indonesia. Dewasa ini, jumlah penyu hijau banyak mengalami penurunan, karena berbagai faktor seperti ada perburuan dan pengambilan telur penyu secara ilegal, serta terjadi degradasi habitat. Dalam penelitian ini dipelajari kondisi habitat peneluran dan fluktuasi jumlah penyu hijau (Chelonia mydas) yang mendarat di Pulau Derawan, Kabupaten Berau-Kalimantan Timur, yang diharapkan dapat dijadikan sebagai bahan masukan bagi pengelolaan habitat penyu. Penelitian yang dilakukan pada bulan Maret dan September 2006 menggunakan metode survei dan pengamatan langsung di lapangan. Deskripsi dari habitat penyu bertelur adalah daratan luas dan landai yang terletak di atas bagian pantai dengan rata-rata kemiringan 30° serta di atas pasang surut antara 30 sampai dengan 50 m. Kondisi pantai berpasir tidak kurang dari 90% dan sisa debu maupun tanah liat dengan diameter butiran halus sampai dengan sedang. Jumlah penyu yang mendarat di Pulau Derawan 408 ekor pada tahun 2004 menurun menjadi 168 ekor pada tahun 2005. Penurunan jumlah penyu hijau (Chelonia mydas) yang mendarat di Pulau Derawan disebabkan oleh menurunnya kondisi lingkungan pantai akibat meningkatnya aktivitas masyarakat, berkurangnya kerapatan vegetasi pantai akibat abrasi, dan berkurangnya ruang tempat peneluran karena pembangunan rumah wisata di pinggir pantai di Pulau Derawan. Green turtle is a most common of six turtles species found in Indonesia. Actualy, this turtle population has much decreased, due to some factors, such as turtle hunting and turtle eggs taking illegally as well as habitat degradation occurrence. The current work studied the condition of nesting habitat and the fluctuation of green turtle (Chelonia mydas) population landed in Derawan Island, Berau District in East Kalimantan, with hope that the results are usefull as input for better management of sea turtle habitat. The study that was conducted on March and September 2006 used survey methods and direct observation in the field. Habitat description of green turtle (Chelonia mydas) shows that the area for nesting is the sandy coast of less than 30° slope, silt as well as compacted beach with small and medium grains diameter, and the difference between low and high tide is 30 to 50 cm. Green turtle (Chelonia mydas) number in the nesting area of Derawan Island was 408 individuals in 2004 and decreased to about 168 individuals in 2005. This condition might be caused by the degradation of nesting habitat environment due to the increase of human activity, decrease of coastal vegetation density by coastal abration, and decrease of nesting habitat caused by the builts of housing and resort in the coastal area of Derawan Island.

scholarly journals Migratory corridor linking Atlantic green turtle, Chelonia mydas, nesting site on Bioko Island, Equatorial Guinea to Ghanaian foraging grounds

PLoS ONE ◽  
2019 ◽  
Vol 14 (6) ◽  
pp. e0213231 ◽  
Author(s):  
Emily Mettler ◽  
Chelsea E. Clyde-Brockway ◽  
Shaya Honarvar ◽  
Frank V. Paladino
Keyword(s):  
Green Turtle ◽  
Chelonia Mydas ◽  
Equatorial Guinea ◽  
Bioko Island ◽  
Nesting Site ◽  
Migratory Corridor
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