scholarly journals Pengaruh Kedalaman Sarang Penetasan Penyu Hijau (Chelonia mydas) terhadap Masa Inkubasi dan Persentase Keberhasilan Penetasan di Pantai Sukamade, Taman Nasional Meru Betiri, Banyuwangi Jawa Timur [Effect of Nesting Site Depth of Green Turtle (Chelonia mydas) on the Incubation Period and Hatching Success Percentage in Sukamade Beach, Meru Betiri National Park, Banyuwangi in East Java]

2019 ◽  
Vol 7 (2) ◽  
pp. 195
Author(s):  
Abang Aldhian R. Putera ◽  
Laksmi Sulmartiwi ◽  
Wahju Tjahjaningsih
Keyword(s):  
Incubation Period ◽  
Green Turtle ◽  
National Park ◽  
Hatching Success ◽  
Sea Turtles ◽  
Chelonia Mydas ◽  
The Other ◽  
Green Turtles ◽  
Egg Incubation ◽  
Range Test

Abstract Indonesia is an archipelago that is rich in diversity of flora and fauna. One of these is a wealth of fauna species of sea turtles. All species of sea turtles in the world by the Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES) put in Appendix I as endangered and protected and not allowed to be traded. The purpose of this study was to determine effect the ratio of the depth from nest egg incubation and hatching percentage of green turtles (Chelonia mydas) nests at different depths in Sukamade, Betiri Meru National Park, Banyuwangi, East Java. The design of the study is a randomized block design (RGD). The groups as replicates for RGD, between groups or experimental material media are considered uniform. The results showed that the average incubation period was 58.87 +0.39 days, then the results were followed by Duncan's multiple range test, which showed that the highest yield obtained by the depth of 50 cm wasn’t significantly different (p> 0.05) with depth of 30 cm and 70 cm. While the results obtained at the lowest depth of 90 cm was significantly different (p <0.05) with the other depth (30 cm, 50 cm and 70 cm). While the percentage of hatching success obtained in average hatching was 88.12 + 0.38%. The Duncan's multiple range test analysis, showed that at a depth of 70 cm were not significantly different (p <0.05) from depth of 50 cm, but 70 and 50 cm depth was significantly different (p> 0.05) from another depth. Whereas the lowest hatching results obtained on depth of 90 cm are significantly different (p> 0.05) from the other depth (30 cm, 50 cm and 70 cm). The conclusion of this study was different depth of green turtle nests affect the egg incubation period and the percentage of egg hatching success of green turtles.

scholarly journals The Effects of Nest Location and Beach Environment on Hatching Success for Leatherback (Dermochelys Coriacea) and Green (Chelonia Mydas) Sea Turtles on Bioko Island, Equatorial Guinea

2021 ◽  
Author(s):  
Callie A. Veelenturf ◽  
Elizabeth M. Sinclair ◽  
Peter Leopold ◽  
Frank V. Paladino ◽  
Shaya Honarvar
Keyword(s):  
Green Turtle ◽  
Hatching Success ◽  
Sea Turtles ◽  
Chelonia Mydas ◽  
Dermochelys Coriacea ◽  
Equatorial Guinea ◽  
Leatherback Turtles ◽  
Nest Location ◽  
Bioko Island ◽  
Elevation Range

Abstract Hatching success in sea turtles is hindered by a variety of biotic and abiotic factors. This study of the nesting ecology of leatherback (Dermochelys coriacea) and green (Chelonia mydas) sea turtles, investigated how several environmental factors and beach characteristics on Bioko Island, Equatorial Guinea influence sea turtle reproductive success. Average clutch hatching success was 40.4% for green turtles and 41.73% for leatherback turtles. For leatherback turtles, clutch elevation relative to the high tide line (HTL) was found to be the most influential factor in determining hatching success, highlighting the sensitivity of this species to sea level rise (SLR). Multiple linear regression analysis demonstrated that nest distance to vegetation and sand conductivity also played significant roles in leatherback clutch hatching success. For leatherback clutches, 33% percent of experimental nests were affected by inundation and 17% by predation. An optimum clutch elevation range for leatherback turtles was identified, where a distinct increase in hatching success was observed between -0.286 m to -0.0528 m above the HTL. For green sea turtles, 64% of experimental nests were affected by predation, confounding conclusions about the roles of environmental characteristics in green turtle hatching success. We propose further investigation into influential characteristics in green turtle nests and confirmation of the observed optimum elevation range on Bioko Island and other nesting grounds. Identified sensitivities of each species to SLR and beach characteristics will be used to encourage the government of Equatorial Guinea to consider the vulnerability of their resident turtle populations when planning for future coastal development.

scholarly journals Incubation temperatures, hatching success and congenital anomalies in green turtle nests from Guanahacabibes Peninsula, Cuba

2021 ◽  
Vol 4 (4) ◽  
pp. 321-330
Author(s):  
Randy Calderón Peña ◽  
Julia Azanza Ricardo
Keyword(s):  
Congenital Anomalies ◽  
Green Turtle ◽  
Thermal Tolerance ◽  
Elevated Temperatures ◽  
Hatching Success ◽  
Incubation Temperature ◽  
Chelonia Mydas ◽  
Sea Turtle ◽  
Green Turtles ◽  
Incubation Temperatures

Elevated incubation temperatures of sea turtle nests decrease hatching success and alter the resulting hatchlings' morphology. There is an absence of studies assessing the relationships between temperature and hatching success in Cuba, even when they could improve understanding the limits of thermal tolerance in these species. This study evaluated the influence of incubation temperature on hatching success and phenotypic malformations in green turtle hatchlings (Chelonia mydas); and analyzed the temporal variation in hatching success on the studied beaches. In 48 green turtles nests distributed along two beaches, incubation temperature and hatching success were recorded between 2014 and 2019. Increasing incubation temperature caused a decrease in the hatching success and an increase in the frequency of supernumerary scutes. Despite the elevated temperatures (average > 30°C), hatching was higher than 80%. Significant differences in hatching success were only observed among seasons for nests in Antonio Beach (lower values in 2016 and 2019 compared to 2014).

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.

Further Studies of the Sea-Finding Mechanism in Green Turtle Hatchlings

Behaviour ◽  
1974 ◽  
Vol 51 (3-4) ◽  
pp. 195-208 ◽  
Author(s):  
Sara J. Shettleworth ◽  
N. Osovsky
Keyword(s):  
Visual Field ◽  
Green Turtle ◽  
Chelonia Mydas ◽  
The Other ◽  
Green Turtles ◽  
Visual Inputs ◽  
Simultaneous Comparison ◽  
Temporal Field ◽  
Different Parts ◽  
Made In

AbstractFurther studies were made of the simultaneous comparison mechanism used by hatchling green turtles, Chelonia mydas, in sea-finding behaviour. The aim was to learn if visual inputs from different directions, stimulating different parts of the retina, had the same effects on orientation. To do this goggles were designed that permitted occlusion of parts of the visual field. Wearing goggles did not in itself affect orientation. When the nasal visual field for one eye and the temporal field for the other eye were covered, turtles circled consistently in the direction of the eye with the nasal occlusion. The total numbers of circles made in a given time by such turtles were not significantly different from those made by animals with simple unilateral blindfolds. Covering the temporal field of one eye resulted in some, though not all, turtles turning contralateral to that eye, provided the other eye was totally covered. On the whole the data were consistent with the idea that inputs in the nasal field are associated with contralateral turning and those in the temporal field with ipsilateral turning. Some complications to this interpretation are also discussed. However, the results demonstrate unequivocally that inputs from different directions contribute differently to sea-finding orientation of green turtles.

scholarly journals A Sea Turtle Population Assessment for Florida's Big Bend, Northeastern Gulf of Mexico

2021 ◽  
Vol 32 ◽  
pp. 19-33
Author(s):  
Ryan Chabot ◽  
Ryan Welsh ◽  
Cody Mott ◽  
Jeffrey Guertin ◽  
Brian Shamblin ◽  
...  
Keyword(s):  
Gulf Of Mexico ◽  
Green Turtle ◽  
Sea Turtles ◽  
Distance Sampling ◽  
Chelonia Mydas ◽  
The United States ◽  
Sea Turtle ◽  
Eretmochelys Imbricata ◽  
Green Turtles ◽  
Big Bend

Coastal waters of Florida’s Big Bend, Gulf of Mexico (GOM) once supported one of the largest sea turtle fisheries in the United States. To fill an information gap in this region on abundance and distribution of sea turtles, we used vessel—based distance sampling and active capture methods to characterize current foraging aggregations near the St. Martins Marsh Aquatic Preserve. Over 10 sampling periods between 2012—2018, we completed 513 km of transects and recorded 819 turtles among 4 species—green turtle (Chelonia mydas, n = 624), Kemp’s ridley (Lepidochelys kempii, n = 147), loggerhead (Caretta caretta, n = 47), and a single hawksbill (Eretmochelys imbricata). Turtle densities in 4 study plots within the 200 km2 study site ranged from 57—221 immature green turtles/km2, 16—56 immature Kemp’s ridleys/km2, and 1—14 juvenile—to—adult loggerheads/km2. Of 200 green turtles captured, 67.5% showed skin tumors consistent with fibropapillomatosis, a frequency similar to that from urbanized estuaries of Florida’s east coast. The largest green turtles (> 60 cm straight standard carapace length), abundant in the southern portion of our study area, are of note because this size class is uncommonly recorded within US territorial waters. Analyses of green turtle mtDNA haplotypes found contributions from rookeries in the western GOM, Mexican Caribbean, and Costa Rica. Although Big Bend protected areas were principally designed to conserve marine and coastal habitats, these regulatory zones have also effectively encompassed a hotspot for foraging sea turtles.

scholarly journals PRIMEROS REGISTROS DE TORTUGAS BLANCAS Chelonia mydas CON FIBROPAPILOMAS, EN YUCATÁN, MÉXICO

2007 ◽  
Vol 22 (1-2) ◽  
pp. 29
Author(s):  
A. Maldonado-Gasca, ◽  
M. Zapata-Rosales
Keyword(s):  
Green Turtle ◽  
Carapace Length ◽  
Sea Turtles ◽  
Chelonia Mydas ◽  
Marine Turtles ◽  
Straight Carapace Length ◽  
Green Turtles ◽  
High Prevalence ◽  
Migratory Route

First reports of green turtles Chelonia mydas with fibropapillomas, in Yucatán, México Fibropapillomas are cutaneous tumors that affect the health of marine turtles worldwide. In July 11th of 1998, a juvenile green turtle (Chelonia mydas) with tumors was captured by fishermen in the Sea Turtles Sanctuary of Rio Lagartos, Yucatán. The straight carapace length of this turtle was 44.6 cm, and we found 30 tumors with a size from 1 cm - 10 cm on the back flippers, neck, front flippers and in both eyes. On July 10th, 1999, another juvenile green turtle with fibropapillomatosis was captured by fishermen in the same area. This turtle was smaller (S.C.L. = 40.8 cm) with 5 small tumors (1 cm - 4 cm) on the back flippers and tail. The prevalence of fibro papillomatosis in Yucatan is low (2.4%). Considering the migratory route of this species and the high prevalence of green turtles with fibropapillomas in Florida, USA, we suggest an initial contagion between the populations of these peninsulas. Those are the first documented reports of green turtles with fibropapillomas in Yucatán, México.

The Effect of Invertebrate Infestation on Green Turtle (Chelonia mydas) Nests on Kazanlı Beach, Mersın, Turkey

2020 ◽  
Vol 27 (5) ◽  
pp. 245-256
Author(s):  
Cemil Aymak ◽  
Aşkın Hasan Uçar ◽  
Yusuf Katılmış ◽  
Eyup Başkale ◽  
Serap Ergene
Keyword(s):  
Green Turtle ◽  
Hatching Success ◽  
Negative Relationship ◽  
Chelonia Mydas ◽  
Sea Turtle ◽  
Faunal Composition ◽  
Independent Variables ◽  
Invertebrate Species ◽  
First Time ◽  
Nesting Season

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.

scholarly journals Dietary analysis of two sympatric marine turtle species in the eastern Mediterranean

2021 ◽  
Vol 168 (6) ◽  
Author(s):  
Josie L. Palmer ◽  
Damla Beton ◽  
Burak A. Çiçek ◽  
Sophie Davey ◽  
Emily M. Duncan ◽  
...  
Keyword(s):  
Green Turtle ◽  
Eastern Mediterranean ◽  
Chelonia Mydas ◽  
Marine Turtle ◽  
Dietary Analysis ◽  
Low Frequencies ◽  
Turtle Species ◽  
Dietary Shift ◽  
Green Turtles ◽  
Loggerhead Turtles

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.

AEROBIC BACTERIAL FLORA OF NESTING GREEN TURTLES (CHELONIA MYDAS) FROM TORTUGUERO NATIONAL PARK, COSTA RICA

2006 ◽  
Vol 37 (4) ◽  
pp. 549-552 ◽  
Author(s):  
Mario Santoro ◽  
Giovanna Hernández ◽  
Magaly Caballero ◽  
Fernando García
Keyword(s):  
Costa Rica ◽  
National Park ◽  
Bacterial Flora ◽  
Chelonia Mydas ◽  
Green Turtles

scholarly journals Redescription of Charaxicephaloides polyorchis Groschaft and Tenora 1978 (Digenea: Pronocephalidae) from the green turtle Chelonia mydas in Costa Rica

2009 ◽  
Vol 46 (2) ◽  
pp. 97-99 ◽  
Author(s):  
M. Santoro ◽  
P. Brandmayr ◽  
E. Greiner ◽  
J. Morales ◽  
B. Rodríguez-Ortíz
Keyword(s):  
Costa Rica ◽  
Host Species ◽  
Green Turtle ◽  
Chelonia Mydas ◽  
Original Description ◽  
Northwest Coast ◽  
Green Turtles ◽  
New Information

AbstractCharaxicephaloides polyorchis Groschaft and Tenora, 1978 is redescribed on the basis of specimens collected from the stomach of green turtles Chelonia mydas in Costa Rica. Our specimens are consistent with the original description which was based on four flukes from the same host species from the northwest coast of Cuba. Our redescription provides a new range of variations and adds new information on this species. This represents only the second record of C. polyorchis in green turtles.

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