Two hundred years after a commercial marine turtle fishery: the current status of marine turtles nesting in the Cayman Islands

AbstractLarge populations of marine turtles breeding in the Cayman Islands were drastically reduced in the early 1800s. However, marine turtle nesting still occurs in the islands. The present-day status of this nesting population provides insight into the conservation of marine turtles, a long-lived species. In 1998 and 1999, the first systematic survey of marine turtle nesting in the Cayman Islands found 38 nests on 22 beaches scattered through the three islands. Three species were found: the green Chelonia mydas, hawksbill Eretmochelys imbricata and loggerhead Caretta caretta turtles. Comparison with other rookeries suggests that the small number of sexually mature adults surviving Cayman's huge perturbations may be impeding population recovery. This shows the need to implement conservation measures prior to massive reductions in population size.

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Two hundred years after a commercial marine turtle fishery: the current status of marine turtles nesting in the Cayman Islands

Oryx ◽

10.1017/s0030605300031707 ◽

2001 ◽

Vol 35 (02) ◽

pp. 145 ◽

Cited By ~ 17

Author(s):

Jonathan J. Aiken ◽

Brendan J. Godley ◽

Annette C. Broderick ◽

Timothy Austin ◽

Gina Ebanks-Petrie ◽

...

Keyword(s):

Marine Turtle ◽

Current Status ◽

Cayman Islands ◽

Marine Turtles

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The importance of north-west Madagascar for marine turtle conservation

Oryx ◽

10.1017/s0030605307001901 ◽

2007 ◽

Vol 41 (2) ◽

pp. 232-238 ◽

Cited By ~ 2

Author(s):

Jessica Metcalf ◽

Katie Hampson ◽

Alain Andriamizava ◽

Rivo Andrianirina ◽

Claudine Ramiarisoa ◽

...

Keyword(s):

Environmental Education ◽

Chelonia Mydas ◽

Marine Turtle ◽

Conservation Priority ◽

Eretmochelys Imbricata ◽

North West ◽

Marine Turtles ◽

Incidental Capture ◽

Turtle Conservation ◽

Nesting Activity

AbstractThe coast of north-west Madagascar is an important nesting and feeding ground for marine turtles, but little is known about populations in this area. From July to December 2000 we documented nesting activity of, and investigated threats to, green Chelonia mydas and hawksbill Eretmochelys imbricata turtles at three sites along this coast: Nosy Iranja, the Radama Islands, and the Nosy Hara archipelago. Levels of nesting activity varied between sites, with green and hawksbill turtle nesting concentrated in different areas. The principal threats identified were opportunistic exploitation of nesting females and incidental capture in fishing nets. Commercial importance of marine turtles was negligible, suggesting conservation measures such as targeted environmental education could have beneficial impacts on these populations. Evidence for high levels of nesting activity reported here indicate that education efforts in these areas should be a conservation priority.

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Status of Marine Turtles in British Columbia Waters: A Reassessment

The Canadian Field-Naturalist ◽

10.22621/cfn.v118i1.885 ◽

2004 ◽

Vol 118 (1) ◽

pp. 72 ◽

Cited By ~ 3

Author(s):

Donald F. McAlpine ◽

Stan A. Orchard ◽

Kelly A. Sendall ◽

Rod Palm

Keyword(s):

British Columbia ◽

Marine Environment ◽

Chelonia Mydas ◽

Marine Turtle ◽

Dermochelys Coriacea ◽

Concerted Effort ◽

Leatherback Turtles ◽

Marine Turtles ◽

Green Turtles

Marine turtles in British Columbia have previously been considered off course stragglers. Here we document 20 new reports for Green Turtles, Chelonia mydas, and Leatherback Turtles, Dermochelys coriacea, for the province. Until recently there had been no concerted effort to acquire data on marine turtle abundance or frequency off British Columbia. Observations presented here allow a reassessment of marine turtle status in British Columbia waters. We suggest Green Turtles and Leatherbacks should be considered rare vagrants and uncommon seasonal residents, respectively, off British Columbia and that they are a natural part of the British Columbia marine environment.

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Natal foraging philopatry in eastern Pacific hawksbill turtles

Royal Society Open Science ◽

10.1098/rsos.170153 ◽

2017 ◽

Vol 4 (8) ◽

pp. 170153 ◽

Cited By ~ 6

Author(s):

Alexander R. Gaos ◽

Rebecca L. Lewison ◽

Michael P. Jensen ◽

Michael J. Liles ◽

Ana Henriquez ◽

...

Keyword(s):

Genetic Research ◽

Eastern Pacific ◽

Marine Turtle ◽

Natal Philopatry ◽

Eretmochelys Imbricata ◽

Turtle Species ◽

Marine Turtles ◽

Complex Processes ◽

Natal Homing ◽

Hawksbill Turtles

The complex processes involved with animal migration have long been a subject of biological interest, and broad-scale movement patterns of many marine turtle populations still remain unresolved. While it is widely accepted that once marine turtles reach sexual maturity they home to natal areas for nesting or reproduction, the role of philopatry to natal areas during other life stages has received less scrutiny, despite widespread evidence across the taxa. Here we report on genetic research that indicates that juvenile hawksbill turtles ( Eretmochelys imbricata ) in the eastern Pacific Ocean use foraging grounds in the region of their natal beaches, a pattern we term natal foraging philopatry. Our findings confirm that traditional views of natal homing solely for reproduction are incomplete and that many marine turtle species exhibit philopatry to natal areas to forage. Our results have important implications for life-history research and conservation of marine turtles and may extend to other wide-ranging marine vertebrates that demonstrate natal philopatry.

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

Oryx ◽

10.1017/s0030605305000372 ◽

2005 ◽

Vol 39 (2) ◽

pp. 137-148 ◽

Cited By ~ 38

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.

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Impact of jaguar Panthera onca (Carnivora: Felidae) predation on marine turtle populations in Tortuguero, Caribbean coast of Costa Rica

Revista de Biología Tropical ◽

10.15517/rbt.v63i3.16537 ◽

2015 ◽

Vol 63 (3) ◽

pp. 815 ◽

Cited By ~ 2

Author(s):

Stephanny Arroyo-Arce ◽

Roberto Salom-Pérez

Keyword(s):

Costa Rica ◽

Chelonia Mydas ◽

Marine Turtle ◽

Dermochelys Coriacea ◽

Panthera Onca ◽

Caribbean Coast ◽

Eretmochelys Imbricata

Existe poco conocimiento sobre el impacto que tienen los jaguares sobre las tortugas marinas que anidan en el Parque Nacional Tortuguero, Costa Rica. Este estudio evaluó el impacto de la depredación de jaguar sobre tres especies de tortugas marinas (Chelonia mydas, Dermochelys coriácea y Eretmochelys imbricata) que anidan en Tortuguero. Los reportes de depredación fueron obtenidos empleando dos metodologías, revisión literaria (eventos registrados antes del 2005) y monitoreos semanales a lo largo de la playa (durante el periodo 2005-2013). La depredación del jaguar se ha incrementado de una tortuga en 1981 a 198 tortugas en 2013. Asimismo, los jaguares consumieron anualmente un promedio de 120 (SD= 45) y 2 (SD= 3) tortugas verdes y tortugas baula en Tortuguero, respectivamente. Nuestros resultados indican que los jaguares no representan una amenaza para la población de tortugas verdes que anida en Tortuguero, y no son la causa principal de la disminución poblacional de la tortuga baula y carey. No obstante, se recomienda continuar con el monitoreo con el fin de entender cómo esta interacción depredador-presa evolucionará en el futuro.

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Chelonia mydas fibropapillomatosis in Baie Blanche, Tintamarre Island Saint Martin (FWI), an environmental sciences and veterinary cross-analysis

10.21203/rs.3.rs-876743/v1 ◽

2021 ◽

Author(s):

Claire SALADIN

Keyword(s):

Early Stage ◽

Health Assessment ◽

Environmental Parameters ◽

Chelonia Mydas ◽

Marine Turtle ◽

Neoplastic Disease ◽

Environmental Pressures ◽

Marine Turtles ◽

Key West ◽

Saint Martin

Abstract Chelonia mydas’s fibropapillomatosis is a panzootic neoplastic disease that has been affecting the species since 1930’s, starting in Key West Florida USA. Most likely induced by the Chelonian HerpesVirus 5 (ChHV5), fibropapillomatosis has been recorded as affecting all species of marine turtles, provoking the growth of malignant external and internal round shaped tumors to marine turtles, that share numerous genomic similarities with human cancers. This research focuses on the two pristine bays of Tintamarre island in Saint Martin (French West Indies), Baie Blanche and Lagon, where the early stage of fibropapillomatosis has been observed affecting juvenile Chelonia mydas resident of Tintamarre. The results obtained when cross-analyzing the environmental monitoring and studies performed of Tintamarre island and a veterinary health assessment of Chelonia mydas juvenile and sub-adult marine turtles of Baie Blanche, bring a different perspective to the environmental pressures that may be responsible of the expression of the disease in Chelonia mydas. Macro-algae and Cadmium (Cd) contamination of marine turtles habitat and foraging grounds are environmental parameters that are found as possibly inducing fibropapillomatosis clinical expression in Tintamarre in this research, concurring with previous publications findings. Tintamarre island in Saint Martin (FWI) is a key site to study pertaining to marine turtle fibropapillomatosis.

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Effectiveness of monitoring techniques employed to determine reproductive success of marine turtles in Cuba

Latin American Journal of Aquatic Research ◽

10.3856/vol43-issue3-fulltext-16 ◽

2017 ◽

Vol 43 (3) ◽

pp. 548-556

Author(s):

Julia Azanza-Ricardo ◽

José Luis Gerhartz-Muro ◽

Yanet Forneiro Martín-Viaña ◽

Félix Moncada-Gavilán

Keyword(s):

Cost Benefit ◽

Chelonia Mydas ◽

Eretmochelys Imbricata ◽

Marine Turtles ◽

Systematic Monitoring ◽

Monitoring Frequency ◽

Monitoring Strategies ◽

Monitoring Effort ◽

The Right ◽

Nesting Beaches

Monitoring of nesting has been used globally to estimate the population size of marine turtles. Nevertheless, monitoring effort varies widely, for instance in Cuba, four different approaches are applied: nighttime systematic monitoring, daytime systematic monitoring, sporadic monitoring with nest verification, and sporadic monitoring with no verification. These variations imply that the amount and accuracy of data gathered and the quality of derived information, differ amongst the approaches. This paper assesses the effectiveness of the different methodologies used for determining the reproduction success of marine turtles in Cuba. Nighttime systematic monitoring is only carried out in one area, while sporadic monitoring with nest verification is the most used approach along the country. The proportion of the nesting season covered with monitoring personnel is low in most of the beaches and for all the three species (Chelonia mydas, Caretta caretta and Eretmochelys imbricata), although the species in the most critical situation is hawksbill. Significant differences were found between systematic and sporadic monitoring, which has important implications for the understanding of the nesting behavior, as the capacity to detect false and true crawls essentially depends on the monitoring frequency, according to our findings. Low detection capacity in sporadic monitoring hampered the development of efficiency assessments in all the nesting beaches. In summary, despite the effort carried out nationwide to monitor nesting populations that has even increased in the last three years, important gaps exists and new monitoring strategies are needed to guarantee the right information for the species is gathered, while adequate cost-benefit balance is achieved.

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Ocular dimensions and schematic eyes of freshwater and sea turtles

Visual Neuroscience ◽

10.1017/s0952523800010415 ◽

1991 ◽

Vol 7 (6) ◽

pp. 627-635 ◽

Cited By ~ 31

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.

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

Australian Journal of Zoology ◽

10.1071/zo9830851 ◽

1983 ◽

Vol 31 (5) ◽

pp. 851 ◽

Cited By ~ 1

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.

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