scholarly journals Fine-scale thermal adaptation in a green turtle nesting population

2011 ◽  
Vol 279 (1731) ◽  
pp. 1077-1084 ◽  
Author(s):  
Sam B. Weber ◽  
Annette C. Broderick ◽  
Ton G. G. Groothuis ◽  
Jacqui Ellick ◽  
Brendan J. Godley ◽  
...  
Keyword(s):  
Green Turtle ◽  
Spatial Scales ◽  
Thermal Adaptation ◽  
Chelonia Mydas ◽  
Breeding Population ◽  
Thermal Reaction ◽  
Marine Turtle ◽  
Conservation Units ◽  
Sand Beach ◽  
Incubation Temperatures

The effect of climate warming on the reproductive success of ectothermic animals is currently a subject of major conservation concern. However, for many threatened species, we still know surprisingly little about the extent of naturally occurring adaptive variation in heat-tolerance. Here, we show that the thermal tolerances of green turtle ( Chelonia mydas ) embryos in a single, island-breeding population have diverged in response to the contrasting incubation temperatures of nesting beaches just a few kilometres apart. In natural nests and in a common-garden rearing experiment, the offspring of females nesting on a naturally hot (black sand) beach survived better and grew larger at hot incubation temperatures compared with the offspring of females nesting on a cooler (pale sand) beach nearby. These differences were owing to shallower thermal reaction norms in the hot beach population, rather than shifts in thermal optima, and could not be explained by egg-mediated maternal effects. Our results suggest that marine turtle nesting behaviour can drive adaptive differentiation at remarkably fine spatial scales, and have important implications for how we define conservation units for protection. In particular, previous studies may have underestimated the extent of adaptive structuring in marine turtle populations that may significantly affect their capacity to respond to environmental change.

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.

scholarly journals Some of them came home: the Cayman Turtle Farm headstarting project for the green turtle Chelonia mydas

Oryx ◽  
2005 ◽  
Vol 39 (2) ◽  
pp. 137-148 ◽  
Author(s):  
Catherine D.L. Bell ◽  
Joe Parsons ◽  
Timothy J. Austin ◽  
Annette C. Broderick ◽  
Gina Ebanks-Petrie ◽  
...  
Keyword(s):  
Chelonia Mydas ◽  
Breeding Population ◽  
Marine Turtle ◽  
Management Technique ◽  
Cayman Islands ◽  
Age At Maturity ◽  
Green Turtles ◽  
Local Breeding ◽  
The Caribbean ◽  
Cayman Turtle Farm

Headstarting is a management technique employed to enhance recruitment of turtles into diminished or extirpated marine turtle populations. Although there have been numerous projects worldwide, there has been a paucity of detailed investigations into its efficacy. Between 1980 and 2001, 16,422 captive-raised hatchlings and 14,347 yearling green marine turtles Chelonia mydas were released from the Cayman Turtle Farm. Approximately 80% of all turtles released were subject to some form of tagging, including living tags. A total of 392 tagged animals have been recaptured at intervals of up to 19 years. Of this total, 160 individuals were captured in the Cayman Islands and 232 were recorded from other locations within the wider Caribbean and southeastern USA. There was significant variation in the release-recapture intervals at the three countries with most returns (Cayman, Cuba and Nicaragua). A positive relationship exists between time at large and size at recapture and data suggest growth rates comparable to those of wild green turtles in the region. There have been at least six living tag returns, four involving turtles released as yearlings and two involving turtles released as hatchlings. This demonstrates an age at maturity that may be as short as 15–19 years, depending on stage of release. Results show that some headstarted turtles are moving around the Caribbean, surviving for long periods of time, contributing to the local breeding population, and are possibly displaying shifts in habitat utilization with age similar to those recorded by wild individuals.

scholarly journals The value of long-term, community-based monitoring of marine turtle nesting: a study in the Lamu archipelago, Kenya

Oryx ◽  
2017 ◽  
Vol 53 (1) ◽  
pp. 71-80 ◽  
Author(s):  
Mike I. Olendo ◽  
Gladys M. Okemwa ◽  
Cosmas N. Munga ◽  
Lilian K. Mulupi ◽  
Lily D. Mwasi ◽  
...  
Keyword(s):  
Green Turtle ◽  
Low Cost ◽  
Western Indian Ocean ◽  
Chelonia Mydas ◽  
Sea Turtle ◽  
Marine Turtle ◽  
Olive Ridley ◽  
Community Based ◽  
Green Turtles ◽  
Incubation Duration

AbstractMonitoring of nesting beaches is often the only feasible and low-cost approach for assessing sea turtle populations. We investigated spatio-temporal patterns of sea turtle nesting activity monitored over 17 successive years in the Lamu archipelago, Kenya. Community-based patrols were conducted on 26 stretches of beach clustered in five major locations. A total of 2,021 nests were recorded: 1,971 (97.5%) green turtleChelonia mydasnests, 31 (1.5%) hawksbillEretmochelys imbricatanests, 8 (0.4%) olive ridleyLepidochelys olivaceanests and 11 (0.5%) unidentified nests. Nesting occurred year-round, increasing during March–July, when 74% of nests were recorded. A stable trend in mean annual nesting densities was observed in all locations. Mean clutch sizes were 117.7 ± SE 1 eggs (range 20–189) for green turtles, 103±SE 6 eggs (range 37–150) for hawksbill turtles, and 103±SE 6 eggs (range 80–133) for olive ridley turtles. Curved carapace length for green turtles was 65–125 cm, and mean annual incubation duration was 55.5±SE 0.05 days. The mean incubation duration for green turtle nests differed significantly between months and seasons but not locations. The hatching success (pooled data) was 81.3% (n = 1,841) and was higher for in situ nests (81.0±SE 1.5%) compared to relocated nests (77.8±SE 1.4%). The results highlight the important contribution of community-based monitoring in Kenya to sustaining the sea turtle populations of the Western Indian Ocean region.

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).

scholarly journals Descrição Anatômica Esquelética da tartaruga verde (Chelonia Mydas) proveniente de encalhe nas unidades de Conservação do Mosaico Jureia-Itatins, Estação Ecológica Tupiniquins e APACIP – Área de Proteção Ambiental Cananeia-Iguape-Peruíbe-SP / Anatomical Skeletal Description of the Green Turtle (Chelonia Mydas) from stranded in the Jureia-Itatins Mosaic Conservation Units, Tupiniquins Ecological Station and Apacip – Cananeia-Iguape-Peruíbe-SP Environmental Protection zone

2021 ◽  
Vol 4 (4) ◽  
pp. 5441-5456
Author(s):  
Edris Queiroz Lopes ◽  
Tatiane Gonçalves De Lima ◽  
Eduardo Forzan Braz ◽  
Nathia Nathaly Rigoglio
Keyword(s):  
Environmental Protection ◽  
Green Turtle ◽  
Chelonia Mydas ◽  
Conservation Units ◽  
Protection Zone

A tartaruga verde (Chelonia mydas) pertencente à família Cheloniidae é uma das espécies marinhas que habita todos os mares, apresentando comportamento altamente migratório com movimentos sazonais em busca de alimentos, além de alternar seu ciclo de vida em diferentes habitats. Embora sua origem seja terrestre, local onde são lentas e vulneráveis e onde fazem oviposição; estas evoluíram e se adaptaram ao ambiente marinho, local no qual se deslocam com rapidez e agilidade. Sua morfologia pode auxiliar na identificação das diferentes espécies de tartarugas marinhas, como por exemplo, número de placas na cabeça, formato das mandíbulas, entre outros. O dimorfismo sexual fica evidente na vida adulta, quando os machos passam a apresentar cauda mais longa e garra das nadadeiras anteriores curvada. Por ser a espécie mais comum no litoral brasileiro e por estar incluída na lista de espécies ameaçadas de extinção em escala mundial, este trabalho teve como objetivo descrever sua morfologia e anatomia esquelética a fim de difundir conhecimento básicos que visam a conservação desta espécie de tartaruga marinha.

scholarly journals Morphological studies of the composition of the Green Turtle (Chelonia mydas) hyoid bones found in Peruibe, Southern Coast of Brazil, Mosaic of Conservation Units Jureia-Itatins

2019 ◽  
Vol 6 (9) ◽  
pp. 285-290
Author(s):  
Edris Queiroz Lopes ◽  
Luana Félix de Melo ◽  
Milena Joice Bressan ◽  
Tatiane Gonçalves Lima ◽  
Rose Eli Grassi Rici ◽  
...  
Keyword(s):  
Green Turtle ◽  
Chelonia Mydas ◽  
Southern Coast ◽  
Conservation Units ◽  
Morphological Studies

scholarly journals Morphophysiological Analysis of Keratobranchial Bone II located in the Hyoid of the Green Turtle (Chelonias mydas) found in Peruíbe, South Coast of Brazil, Mosaic of Conservation Units-Juréia-Itatins and APACIP

2021 ◽  
Vol 1 (4) ◽  
pp. 120-130
Author(s):  
Edris Queiroz Lopes ◽  
Tatiane Gonçalves De Lima ◽  
Luana Félix De Melo ◽  
Rose Eli Grassi Rici
Keyword(s):  
Green Turtle ◽  
Bone Structure ◽  
Eating Habits ◽  
Coastal Region ◽  
Chelonia Mydas ◽  
Conservation Units ◽  
Green Turtles ◽  
Small Bones ◽  
High Level ◽  
Microscopy Techniques

The green turtle (Chelonia mydas) present in tropical seas, uses as a feeding area the coastal region of Peruíbe, has the skull as a relatively large and solid structure, and a strong jaw formed by the junction of small bones as it has very abrasive feeding. By applying scanning electron microscopy techniques, it was possible to identify the presence of a bone structure located in the hyoid in the ventral region of the skull along with the mandible of juvenile individuals of green turtles, and as there is no related research, it was necessary to perform a CT scan, decalcification and histology of the quelonian hyoid, to discover the morphological composition of this new structure, described only in the species Chelonia mydas. Thus, the morphology of the structures and its confirmation as a real bone, with characteristic of spongy bone, described as certobranchial II, was confirmed, thus helping researchers to seek other ways to understand the feeding processes of these animals that are going through a series of serious environmental problems and therefore perhaps having to change their eating habits to overcome the high level of pollution that we are finding in the oceans.   RESUMO A tartaruga verde (Chelonia mydas) presente nos mares tropicais, utiliza como zona de alimentação a região costeira do Peruíbe, tem o crânio como uma estrutura relativamente grande e sólida, e uma mandíbula forte formada pela junção de pequenos ossos, uma vez que tem uma alimentação muito abrasiva. Aplicando técnicas de microscopia electrónica de varrimento, foi possível identificar a presença de uma estrutura óssea localizada no hióide na região ventral do crânio, juntamente com a mandíbula de indivíduos juvenis de tartarugas verdes, e como não existe investigação relacionada, foi necessário realizar um TAC, descalcificação e histologia do hióide quelónico, para descobrir a composição morfológica desta nova estrutura, descrita apenas na espécie Chelonia mydas. Assim, a morfologia das estruturas e a sua confirmação como um osso real, com característica de osso esponjoso, descrito como certobranchial II, foi confirmada, ajudando assim os investigadores a procurar outras formas de compreender os processos de alimentação destes animais que estão a passar por uma série de graves problemas ambientais e, por conseguinte, talvez tenham de alterar os seus hábitos alimentares para superar o elevado nível de poluição que estamos a encontrar nos oceanos.

scholarly journals Integrating morphological and genetic data at different spatial scales in a cosmopolitan marine turtle species: challenges for management and conservation

2020 ◽  
Author(s):  
Rocío Álvarez-Varas ◽  
Maike Heidemeyer ◽  
Cynthia Riginos ◽  
Hugo A Benítez ◽  
Eduardo Reséndiz ◽  
...  
Keyword(s):  
Genetic Structure ◽  
Population Genetic Structure ◽  
Population Genetic ◽  
Spatial Scales ◽  
Chelonia Mydas ◽  
Marine Turtle ◽  
Adaptive Divergence ◽  
Shape Variation ◽  
Turtle Species ◽  
Cosmopolitan Species

Abstract Patterns of genetic structure in highly mobile marine vertebrates may be accompanied by phenotypic variation. Most studies in marine turtles focused on population genetic structure have been performed at rookeries. We studied whether genetic and morphological variation of the endangered green turtle (Chelonia mydas) is consistent geographically, focusing on foraging grounds. An association between population genetic structure and body shape variation at broad (inter-lineage) and fine (foraging grounds) scales was predicted and analysed using mitochondrial DNA and geometric morphometrics. Although genetic and phenotypic differentiation patterns were congruent between lineages, no fine-scale association was found, suggesting adaptive divergence. Connectivity among Pacific foraging grounds found here suggests that temperatures of ocean surface currents may influence the genetic structure of C. mydas on a broad scale. Our results suggest that vicariance, dispersal, life-history traits and ecological conditions operating in foraging grounds have shaped the intraspecific morphology and genetic diversity of this species. Considering a range of geographic and temporal scales is useful when management strategies are required for cosmopolitan species. Integrating morphological and genetic tools at different spatial scales, conservation management is proposed based on protection of neutral and adaptive diversity. This approach opens new questions and challenges, especially regarding conservation genetics in cosmopolitan species.

Relationship of parasites (Trematoda: Spirorchidae) and their eggs to the occurrence of fibropapillomas in the green turtle (Chelonia mydas)

1995 ◽  
Vol 52 (S1) ◽  
pp. 84-89 ◽  
Author(s):  
Murray D. Dailey ◽  
Robert Morris
Keyword(s):  
Green Turtle ◽  
Sea Turtles ◽  
Chelonia Mydas ◽  
Breeding Population ◽  
Negative Effects ◽  
Tissue Sections ◽  
The Family ◽  
Relationship Of ◽  
The Relationship

The prevalence of green turtle (Chelonia mydas) fibropapillomatosis is increasing in Hawaii, raising the possibility of long-term negative effects on the breeding population. As the etiology of this disease is unknown, our objective was to determine if any relationship exists between fibropapillomas and trematode eggs from the family Spirorchidae, whose presence in tissue sections has been noted for years. A process for tumor digestion and egg extraction was developed and a total of 61 tumors of all sizes was examined to determine the total numbers of eggs present and the species of spirorchid involved. Twelve samples of normal turtle tissue were also examined. Eggs of one to three spirorchid species (Leardius learedi Price, 1934; Haplotrema dorsopora Dailey, Fast and Balazs, 1993; and Carettacola hawaiiensis Dailey, Fast and Balazs, 1991) were recovered from all tumors and nontumored tissues digested. Five turtles were injected with spirorchid eggs and observed for 12 months. New tumors developed on two of the turtles at noninjected sites. Although attempts to induce fibropapillomas through injection were not successful, the presence of spirorchid eggs in every tumor examined raises additional questions regarding the relationship between these parasites and fibropapillomas in sea turtles.

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