scholarly journals Trialling seawater irrigation to combat the high nest temperature feminisation of green turtle (Chelonia mydas) hatchlings

Author(s):  
CE Smith ◽  
DT Booth ◽  
A Crosby ◽  
JD Miller ◽  
MN Staines ◽  
...  
Author(s):  
Graeme C. Hays ◽  
Colin R. Adams ◽  
Jeanne A. Mortimer ◽  
J.R. Speakman

Nest temperatures for green turtles (Chelonia mydas) nesting on Ascension Island, South Atlantic (7°57'S 14°22'W), were examined. Temperature probes were placed into nests on two beaches, Long Beach (26 nests) and North East Bay (8 nests). Within these beaches there was relatively little thermal variation (SD of nest temperature was 0.32°C for Long Beach and 0.30°C for North East Bay). To examine inter-beach thermal variation temperature probes were buried at 55 cm on 12 beaches. Inter-beach thermal variation was large and was related to the beach albedo with the darkest beach (albedo, 016) being 4.2°C warmer than the lightest coloured beach (albedo, 0.73).


2018 ◽  
Vol 46 (2) ◽  
pp. 42
Author(s):  
Desi Nova Sari ◽  
Muhammad Fauzi ◽  
Eni Sumiarsih

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.


2014 ◽  
Vol 37 (2) ◽  
pp. 177-182
Author(s):  
Ç Kılıç ◽  
◽  
O. Candan ◽  

We investigated the relationship between nest parameters, hatchling body mass, and sex ratio of green turtle, Chelonia mydas, embryos and hatchlings at the temperate nesting rookery of Sugözü Beach (Adana–Turkey). Mean nest temperature and distance from the sea were correlated, while mean nest temperature and incubation period were inversely related. There was no apparent relationship between incubation period and hatchling mass. Hatchling and embryo sex ratios, determined by histological examination, showed a 70.5% and 93.5% female bias, respectively. There was no correlation between sex and body weight of hatchlings,


2019 ◽  
Vol 1 (02) ◽  
pp. 64-67
Author(s):  
Meilisha Putri Pertiwi ◽  
Suci Siti Lathifah

Research on the condition of the nesting habitat of Chelonia mydas (green turtle) in Pangumbahan Beach, Ujung Genteng, South Sukabumi has been carried out. Data retrieval is done 6 times for 2 days, 27-28 November 2017 at 3 observation stations. The abiotic parameters measured include surface temperature and depth of 50 cm, surface humidity and depth of 50 cm, beach width, beach slope, and the size of sand grains. While the biotic parameters measured were density, relative density, the frequency of attendance, and distribution patterns of Pandanus tectorius (sea pandanus) vegetation. Based on the results of data processing, the biophysical conditions in Pangumbahan Beach are still suitable for the Chelonia mydas nesting habitat. It also got clear evidence of the many Chelonia mydas landings during the data collection.


2020 ◽  
Vol 13 (3) ◽  
pp. 585-591
Author(s):  
Luana Melo ◽  
Isabel Velasco ◽  
Julia Aquino ◽  
Rosangela Rodrigues ◽  
Edris Lopes ◽  
...  

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.


2018 ◽  
Vol 17 (2) ◽  
pp. 169
Author(s):  
Luis G. Fonseca ◽  
Pilar Santidrián Tomillo ◽  
Wilbert N. Villachica ◽  
Wagner M. Quirós ◽  
Marta Pesquero ◽  
...  

2020 ◽  
Vol 27 (5) ◽  
pp. 245-256
Author(s):  
Cemil Aymak ◽  
Aşkın Hasan Uçar ◽  
Yusuf Katılmış ◽  
Eyup Başkale ◽  
Serap Ergene

In this study invertebrate infestation in green turtle (Chelonia mydas) nests were recorded for the first time for Kazanlı beach, Mersin, Turkey. For this aim, in 2006 nesting season, 294 natural intact green turtle nests were sampled to examine their contents and invertebrate infestation was found in 76 (25.85% of the total sampling green turtle nests). These infested nests were examined in terms of the invertebrate faunal composition. The specimens found in the green sea turtle nests were identified to order, family or genus levels and they were represented in 5 orders. These invertebrate groups are Elater sp. larvae (Elateridae; Coleoptera), Pimelia sp. larvae (Tenebrionidae; Coleoptera), Enchytraeidae (Oligochaeta), Cyrptostigmata (Acari), Oniscidae (Isopoda), Formicidae (Hymenoptera). Elater sp. was the most common invertebrate group in the green turtle nests. According to student t test, we found statistically significant differences between 7 independent variables and invertebrate species presence. Furthermore, logistic regression analysis explained that there is a negative relationship between hatching success rate and invertebrate species presence.


1992 ◽  
Vol 65 (2) ◽  
pp. 287-310 ◽  
Author(s):  
Nigel H. West ◽  
Patrick J. Butler ◽  
Richard M. Bevan

2021 ◽  
Vol 204 ◽  
pp. 105521 ◽  
Author(s):  
Isabella Reboul ◽  
David Booth ◽  
Uzair Rusli
Keyword(s):  

2021 ◽  
Vol 168 (6) ◽  
Author(s):  
Josie L. Palmer ◽  
Damla Beton ◽  
Burak A. Çiçek ◽  
Sophie Davey ◽  
Emily M. Duncan ◽  
...  

AbstractDietary studies provide key insights into threats and changes within ecosystems and subsequent impacts on focal species. Diet is particularly challenging to study within marine environments and therefore is often poorly understood. Here, we examined the diet of stranded and bycaught loggerhead (Caretta caretta) and green turtles (Chelonia mydas) in North Cyprus (35.33° N, 33.47° E) between 2011 and 2019. A total of 129 taxa were recorded in the diet of loggerhead turtles (n = 45), which were predominantly carnivorous (on average 72.1% of dietary biomass), foraging on a large variety of invertebrates, macroalgae, seagrasses and bony fish in low frequencies. Despite this opportunistic foraging strategy, one species was particularly dominant, the sponge Chondrosia reniformis (21.5%). Consumption of this sponge decreased with increasing turtle size. A greater degree of herbivory was found in green turtles (n = 40) which predominantly consumed seagrasses and macroalgae (88.8%) with a total of 101 taxa recorded. The most dominant species was a Lessepsian invasive seagrass, Halophila stipulacea (31.1%). This is the highest percentage recorded for this species in green turtle diet in the Mediterranean thus far. With increasing turtle size, the percentage of seagrass consumed increased with a concomitant decrease in macroalgae. Seagrass was consumed year-round. Omnivory occurred in all green turtle size classes but reduced in larger turtles (> 75 cm CCL) suggesting a slow ontogenetic dietary shift. Macroplastic ingestion was more common in green (31.6% of individuals) than loggerhead turtles (5.7%). This study provides the most complete dietary list for marine turtles in the eastern Mediterranean.


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