scholarly journals Buried treasure—marine turtles do not ‘disguise’ or ‘camouflage’ their nests but avoid them and create a decoy trail

2020 ◽  
Vol 7 (5) ◽  
pp. 200327
Author(s):  
Thomas J. Burns ◽  
Rory R. Thomson ◽  
Rosemary A. McLaren ◽  
Jack Rawlinson ◽  
Euan McMillan ◽  
...  
Keyword(s):  
Nest Site ◽  
Sea Turtles ◽  
Movement Patterns ◽  
Dermochelys Coriacea ◽  
Egg Development ◽  
Eretmochelys Imbricata ◽  
Local Conditions ◽  
Marine Turtles ◽  
Recorded Activity ◽  
Egg Chamber

After laying their eggs and refilling the egg chamber, sea turtles scatter sand extensively around the nest site. This is presumed to camouflage the nest, or optimize local conditions for egg development, but a consensus on its function is lacking. We quantified activity and mapped the movements of hawksbill ( Eretmochelys imbricata ) and leatherback ( Dermochelys coriacea ) turtles during sand-scattering. For leatherbacks, we also recorded activity at each sand-scattering position. For hawksbills, we recorded breathing rates during nesting as an indicator of metabolic investment and compared with published values for leatherbacks. Temporal and inferred metabolic investment in sand-scattering was substantial for both species. Neither species remained near the nest while sand-scattering, instead moving to several other positions to scatter sand, changing direction each time, progressively displacing themselves from the nest site. Movement patterns were highly diverse between individuals, but activity at each sand-scattering position changed little between completion of egg chamber refilling and return to the sea. Our findings are inconsistent with sand-scattering being to directly camouflage the nest, or primarily for modifying the nest-proximal environment. Instead, they are consistent with the construction of a series of dispersed decoy nests that may reduce the discovery of nests by predators.

scholarly journals Chelonid Alphaherpesvirus 5 Prevalence and First Confirmed Case of Sea Turtle Fibropapillomatosis in Grenada, West Indies

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1490
Author(s):  
Amanda James ◽  
Annie Page-Karjian ◽  
Kate E. Charles ◽  
Jonnel Edwards ◽  
Christopher R. Gregory ◽  
...  
Keyword(s):  
West Indies ◽  
Sea Turtles ◽  
Chelonia Mydas ◽  
Sea Turtle ◽  
Dermochelys Coriacea ◽  
Neoplastic Disease ◽  
Extrinsic Factors ◽  
Eretmochelys Imbricata ◽  
Specific Pcr ◽  
The Impact

Chelonid alphaherpesvirus 5 (ChHV5) is strongly associated with fibropapillomatosis, a neoplastic disease of sea turtles that can result in debilitation and mortality. The objectives of this study were to examine green (Chelonia mydas), hawksbill (Eretmochelys imbricata), and leatherback (Dermochelys coriacea) sea turtles in Grenada, West Indies, for fibropapillomatosis and to utilize ChHV5-specific PCR, degenerate herpesvirus PCR, and serology to non-invasively evaluate the prevalence of ChHV5 infection and exposure. One-hundred and sixty-seven turtles examined from 2017 to 2019 demonstrated no external fibropapilloma-like lesions and no amplification of ChHV5 DNA from whole blood or skin biopsies. An ELISA performed on serum detected ChHV5-specific IgY in 18/52 (34.6%) of green turtles tested. In 2020, an adult, female green turtle presented for necropsy from the inshore waters of Grenada with severe emaciation and cutaneous fibropapillomas. Multiple tumors tested positive for ChHV5 by qPCR, providing the first confirmed case of ChHV5-associated fibropapillomatosis in Grenada. These results indicate that active ChHV5 infection is rare, although viral exposure in green sea turtles is relatively high. The impact of fibropapillomatosis in Grenada is suggested to be low at the present time and further studies comparing host genetics and immunologic factors, as well as examination into extrinsic factors that may influence disease, are warranted.

Ocular dimensions and schematic eyes of freshwater and sea turtles

1991 ◽  
Vol 7 (6) ◽  
pp. 627-635 ◽  
Author(s):  
D. P. M. Northmore ◽  
A. M. Granda
Keyword(s):  
Refractive Error ◽  
Sea Turtles ◽  
Chelonia Mydas ◽  
Freshwater Turtle ◽  
Eretmochelys Imbricata ◽  
Marine Turtles ◽  
Pseudemys Scripta

AbstractMeasurements were made of the ocular dimensions from living and frozen eyes of one species of freshwater turtle, Pseudemys scripta elegans, and of three species of marine turtles, Chelonia mydas, Dermochelys cariacea, and Eretmochelys imbricata. Estimates of refractive error by retinoscopy were also obtained with eyes in air and under water. The results suggest that unaccommodated eyes of all four species are approximately emmetropic in air but strongly hyperopic in water. Schematic eyes were calculated for each species in both air and water.

Paramphistomes (Digenea; Paramphistomidae) Parasitic in Marine Turtles (Reptilia: Chelonia).

1983 ◽  
Vol 31 (5) ◽  
pp. 851 ◽  
Author(s):  
D Blair
Keyword(s):  
Green Turtle ◽  
Sea Turtles ◽  
Chelonia Mydas ◽  
Original Material ◽  
Eretmochelys Imbricata ◽  
Marine Turtles ◽  
Australian Region ◽  
Species Inquirenda ◽  
Australian Specimen

Schizamphistomum scleroporum (Creplin, 1844) Groschaft, Otero & Tenora, 1977 nec Looss, 1912, and S. erratum, sp. nov. [=S. scleroporum sensu Looss, 1912 (nec Creplin, 1844)], are described from the green turtle, Chelonia mydas (L.), from Australia. One specimen of the former species was also recovered from an Australian specimen of the hawksbill turtle, Eretmochelys imbricata (L.). Paramphistomum papillostomum MacCallum, 1916 and Schizamphistomoides chelonei Gupta, 1961, are regarded as synonyms of Schizamphistomum scleroporum (Creplin). S. taiwanense Fischthal & Kunz, 1975 is regarded as a species inquirenda. The remaining species known from sea turtles, Schizamphistomoides spinulosum (Looss, 1901) Stunkard, 1925, is redescribed, mostly from original material collected by Looss. This species has not yet been found in the Australian region. The relationships between Schizamphistomum scleroporum, S. erratum and Schizamphntomoides spinulosum are discussed.

scholarly journals Strandings of sea turtles on beaches around the oil capital in Brazil

2021 ◽  
Vol 16 (4) ◽  
pp. 521-538
Author(s):  
Raísa da Silva Costa Rêgo ◽  
Eric Azevedo Cazetta ◽  
Caio Henrique Gonçalves Cutrim ◽  
Amanda Soares Miranda ◽  
Ana Paula Albano Araújo ◽  
...  
Keyword(s):  
Sea Turtles ◽  
Chelonia Mydas ◽  
Sea Turtle ◽  
The State ◽  
Dermochelys Coriacea ◽  
Anthropogenic Factors ◽  
Long Beach ◽  
Eretmochelys Imbricata ◽  
Lepidochelys Olivacea ◽  
The North

The south-western region of the Atlantic Ocean has feeding and nesting areas for the five species of sea turtles registered in Brazil, which are in different degrees of extinction threat, mainly due to anthropogenic factors. Fishing and the ingestion of solid waste, were identified as causing stranding and the mortality of sea turtles. In this work, data from the monitoring of beaches in the Municipalities of Macaé and Rio das Ostras, important oil zone in Brazil, in the north-central region of the State of Rio de Janeiro, were used in order to analyse the effects of seasonality on the sea turtle stranding. The monitoring was carried out daily from September 2017 to June 2019, in a study area covering 23.8 km long beach. Stranding data were obtained from active (n = 126) and passive (n = 66) monitoring of beaches and included the records of Chelonia mydas (n = 151), Caretta caretta (n = 23), Lepidochelys olivacea (n = 14), Dermochelys coriacea (n = 2) and Eretmochelys imbricata (n = 1). The largest stranding record occurred in the summer (n = 61) and spring (n = 60), a period compatible with the reproductive season of the species. The results obtained in this study emphasise the importance of the analysis of strandings of sea turtles, which provide relevant data on the biology of the group, the intra and interspecific dynamics and the state of conservation of these animals.

scholarly journals Checklist of sea turtles endohelminth in Neotropical region

2016 ◽  
Vol 53 (3) ◽  
pp. 211-223 ◽  
Author(s):  
M. R. Werneck ◽  
R. J. Da Silva
Keyword(s):  
Sea Turtles ◽  
Loggerhead Turtle ◽  
Chelonia Mydas ◽  
Neotropical Region ◽  
Dermochelys Coriacea ◽  
Olive Ridley ◽  
Eretmochelys Imbricata ◽  
Leatherback Turtle ◽  
Lepidochelys Olivacea ◽  
The Caribbean

SummaryThis paper presents a list of parasites described in sea turtles from the Neotropical region. Through the review of literature the occurrence of 79 taxa of helminthes parasites were observed, mostly consisting of the Phylum Platyhelminthes with 76 species distributed in 14 families and 2 families of the Phylum Nematoda within 3 species. Regarding the parasite records, the most studied host was the green turtle (Chelonia mydas) followed by the hawksbill turtle (Eretmochelys imbricata), olive ridley turtle (Lepidochelys olivacea), loggerhead turtle (Caretta caretta) and leatherback turtle (Dermochelys coriacea). Overall helminths were reported in 12 countries and in the Caribbean Sea region. This checklist is the largest compilation of data on helminths found in sea turtles in the Neotropical region.

scholarly journals First field observation of the predation by Jaguar (Panthera onca) on Olive Ridley sea turtle (Lepidochelys olivacea) at Nancite Beach, Santa Rosa National Park, Costa Rica

2016 ◽  
Vol 3 (1) ◽  
pp. 20-23
Author(s):  
Sergio Escobar-Lasso ◽  
Luis Fonseca ◽  
Wilbert N. Villachica ◽  
Hansel Herrera ◽  
Roldán A. Valverde ◽  
...  
Keyword(s):  
Costa Rica ◽  
Sea Turtles ◽  
Chelonia Mydas ◽  
Sea Turtle ◽  
Dermochelys Coriacea ◽  
Olive Ridley ◽  
Eretmochelys Imbricata ◽  
Lepidochelys Olivacea ◽  
Santa Rosa National Park ◽  
Key Resources

Jaguars have been recorded preying on adult female sea turtles on their nesting beaches in Costa Rica, Guyana, Mexico and Suriname (Fretey 1977, Autar 1994, Cuevas et al. 2014, Guildera et al. 2015). Jaguars prey on Green (Chelonia mydas), Olive Ridley (Lepidochelys olivacea), Hawksbill (Eretmochelys imbricata), and Leatherback (Dermochelys coriacea) sea turtles (see Fretey 1977, Autar 1994, Carrillo et al. 1994, Chinchilla 1997, Tröeng 2000, Heithaus et al. 2008, Veríssimo et al. 2012, Arroyo-Arce et al. 2014, Cuevas et al. 2014, Arroyo-Arce & Salom-Pérez 2015, Guildera et al. 2015). The capture effort and risk of injury associated with the predation of nesting sea turtles is expected to be lower relative to other prey species in the jaguar’s diet (Cavalcanti & Gese 2010). Additionally, they can be key resources when other pr ey availability is low (Veríssimo et al. 2012).

scholarly journals Saqueo y depredación de nidadas de tortugas marinas, durante las temporadas 2003 a 2012, en seis playas del Golfo de Paria, Venezuela

1969 ◽  
Vol 6 (2) ◽  
pp. 239-244
Author(s):  
Clemente Balladares ◽  
Eva Dubois
Keyword(s):  
Chelonia Mydas ◽  
Sea Turtle ◽  
Dermochelys Coriacea ◽  
Eretmochelys Imbricata ◽  
Marine Turtles ◽  
Team Activity ◽  
The Common ◽  
Cerdocyon Thous

Poaching and predation of sea turtle clutches, during the 2003 and 2012 seasons, on six beaches of the Paria Gulf in Venezuela. Looting and predation of nests are among the major threats to marine turtles. Six beaches of Paria Gulf, northeastern Venezuela, have been protected and had a reduction of clutch poaching and predation on leatherback (Dermochelys coriacea), green (Chelonia mydas), and hawksbill (Eretmochelys imbricata) turtles. During ten years (2003-2012) of nesting seasons (March through October) the six beaches were observed for nesting, poaching and predation. The most frequent losses are caused by poaching, followed by the common fox (Cerdocyon thous), opossum (Didelphis marsupialis) and tamandua (Tamandua tetradactila). The most poached beach is Silvano, followed by Los Garzos (main nesting beach at the site) and Cerezo, which is more distant from the conservation team activity.

scholarly journals The distribution and conservation status of marine turtles in The Gambia, West Africa: a first assessment

Oryx ◽  
2004 ◽  
Vol 38 (2) ◽  
pp. 203-208 ◽  
Author(s):  
Linda K. Barnett ◽  
Craig Emms ◽  
Alpha Jallow ◽  
Anna Mbenga Cham ◽  
Jeanne A. Mortimer
Keyword(s):  
Conservation Status ◽  
Chelonia Mydas ◽  
The Gambia ◽  
Dermochelys Coriacea ◽  
Olive Ridley ◽  
Leatherback Turtles ◽  
Eretmochelys Imbricata ◽  
Lepidochelys Olivacea ◽  
Marine Turtles ◽  
Green Turtles

This paper reports the first systematic survey of the marine turtles of the 80 km of Gambian coastline, and brings together new data and all past records and reports of marine turtles in The Gambia. Green turtles Chelonia mydas are the most abundant turtles and this is the only species so far observed nesting in The Gambia, with peak nesting between August and October. Although 75% (60 km) of The Gambian coastline appears to be suitable for turtle nesting, most nesting activity is confined to the southern coastline. Offshore foraging habitat is apparently extensive. Strandings of green turtles, olive ridley turtles Lepidochelys olivacea, leatherback turtles Dermochelys coriacea and hawksbill turtles Eretmochelys imbricata have been recorded, but we were unable to find evidence for loggerhead turtles Caretta caretta. Threats are mainly of human origin, and include illegal harvesting of eggs, juveniles and adults, as well as mortality as fisheries bycatch, including trawling. One stranded green turtle apparently had fibropapilloma disease. The major threat to nesting habitats is erosion and unregulated development of the coast for tourism. Marine turtles are fully protected under Gambian law. Other national efforts to conserve turtles in The Gambia are described and assessed.

scholarly journals Sea turtles of Madagascar – their status, exploitation and conservation

Oryx ◽  
1994 ◽  
Vol 28 (1) ◽  
pp. 51-61 ◽  
Author(s):  
Berthin Rakotonirina ◽  
Andrew Cooke
Keyword(s):  
Coastal Waters ◽  
Sea Turtles ◽  
Loggerhead Turtle ◽  
Chelonia Mydas ◽  
Dermochelys Coriacea ◽  
Olive Ridley ◽  
Eretmochelys Imbricata ◽  
Lepidochelys Olivacea ◽  
Average Size ◽  
Hawksbill Turtles

Five species of sea turtles are known from Madagascar's coastal waters. Fishermen on the western and south-western coasts take green turtle Chelonia mydas, loggerhead turtle Caretta caretta and olive ridley Lepidochelys olivacea for their meat. The hawksbill turtle Eretmochelys imbricata is taken mainly for its shell and for making stuffed specimens while the leatherback Dermochelys coriacea is seldom caught. Anecdotal evidence of fishermen and dealers in turtle products, measurement of captured animals and personal observations of the authors all point to declines in numbers and average size for green and hawksbill turtles, coupled with marked declines in nesting rates for these and the olive ridley.

scholarly journals Turtle riders: remoras on marine turtles in Southwest Atlantic

2006 ◽  
Vol 4 (1) ◽  
pp. 123-126 ◽  
Author(s):  
Ivan Sazima ◽  
Alice Grossman
Keyword(s):  
Chelonia Mydas ◽  
Oceanic Islands ◽  
Dermochelys Coriacea ◽  
Southwest Atlantic ◽  
Eretmochelys Imbricata ◽  
Turtle Species ◽  
Symbiotic Associations ◽  
Marine Turtles ◽  
Open Sea ◽  
Sw Atlantic

An overview is presented for a poorly documented relationship between reef vertebrates in Southwest Atlantic: remoras (Echeneidae) associated with marine turtles. Two remora species (Echeneis naucrates and Remora remora) and four turtle species (Caretta caretta, Chelonia mydas, Eretmochelys imbricata, and Dermochelys coriacea) are here recorded in symbiotic associations in the SW Atlantic. Echeneis naucrates was recorded both on the coast and on oceanic islands, whereas R. remora was recorded only at oceanic islands and in the open sea. The remora-turtle association is usually regarded as an instance of phoresis (hitchhiking), albeit feeding by the fish is also involved in this symbiosis type. This association seems to be rare in SW Atlantic.

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