scholarly journals Signs of hope in the eastern Pacific: international collaboration reveals encouraging status for a severely depleted population of hawksbill turtles Eretmochelys imbricata

Oryx ◽  
2010 ◽  
Vol 44 (4) ◽  
pp. 595-601 ◽  
Author(s):  
Alexander R. Gaos ◽  
F.A. Abreu-Grobois ◽  
J. Alfaro-Shigueto ◽  
D. Amorocho ◽  
R. Arauz ◽  
...  
Keyword(s):  
El Salvador ◽  
Working Group ◽  
Eastern Pacific ◽  
Marine Turtle ◽  
Current Status ◽  
Eretmochelys Imbricata ◽  
Conservation Projects ◽  
Available Information ◽  
Nesting Activity ◽  
Hawksbill Turtles

AbstractWhile little is known about hawksbill turtles Eretmochelys imbricata in the eastern Pacific Ocean, available information suggests that the population has declined substantially in recent decades and could be near extirpation in the region. To evaluate the current status of the population more effectively and to determine the feasibility of recovery efforts, a workshop of regional marine turtle specialists was held in June 2008 in Los Cóbanos, El Salvador. An international working group, Iniciativa Carey del Pacífico Oriental (ICAPO; Eastern Pacific Hawksbill Initiative in English), was established to consolidate information, promote conservation projects and raise awareness about the species. We present information derived from the workshop and compiled by the ICAPO working group since that time. Considering only records from 1 January 2007 to 31 May 2009 it appears that El Salvador hosts the majority of known hawksbill turtle nesting activity in the eastern Pacific, with 79.6% (n = 430) of all nesting observation records, and Mexico hosts the majority of records of hawksbill turtles at sea, with 60.3% (n = 44) of all in-water observation records. Although current abundance is very low, the pervasiveness of the species in the region suggests potential for conservation and recovery. Despite a historical paucity of research focusing on this population, the relatively large and steadily increasing number of records as a result of concerted efforts demonstrates the viability of the ICAPO network as an instrument to promote conservation of this species in the eastern Pacific.

scholarly journals Natal foraging philopatry in eastern Pacific hawksbill turtles

2017 ◽  
Vol 4 (8) ◽  
pp. 170153 ◽  
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.

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

Oryx ◽  
2001 ◽  
Vol 35 (2) ◽  
pp. 145-151 ◽  
Author(s):  
Jonathan J. Aiken ◽  
Brendan J. Godley ◽  
Annette C. Broderick ◽  
Timothy Austin ◽  
Gina Ebanks-Petrie ◽  
...  
Keyword(s):  
Chelonia Mydas ◽  
Marine Turtle ◽  
Current Status ◽  
Cayman Islands ◽  
Eretmochelys Imbricata ◽  
Marine Turtles ◽  
Mature Adults ◽  
Large Populations ◽  
Sexually Mature ◽  
Insight Into

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.

Long-distance migrations by the hawksbill turtle, Eretmochelys imbricata, from north-eastern Australia

1998 ◽  
Vol 25 (1) ◽  
pp. 89 ◽  
Author(s):  
Jeffrey D. Miller ◽  
Kirstin A. Dobbs ◽  
Colin J. Limpus ◽  
Neil Mattocks ◽  
André M. Landry Jr
Keyword(s):  
Adult Female ◽  
Solomon Islands ◽  
Satellite Telemetry ◽  
Marine Turtle ◽  
Long Distance ◽  
Eretmochelys Imbricata ◽  
Turtle Species ◽  
Eastern Australia ◽  
Nesting Beaches ◽  
Hawksbill Turtles

Tag recoveries from four adult female hawksbill turtles, Eretmochelys imbricata, tagged on the Great Barrier Reef, Australia, are reported. Hawksbill turtles on breeding migrations move between Australia and neighbouring countries including Vanuatu, Solomon Islands, Papua New Guinea and Indonesia. Migratory distances between foraging areas and nesting beaches ranged from 368 to 2425 km. A review of data from tag recoveries, genetic analysis and satellite telemetry indicates that adult female hawksbill turtles often exhibit migratory behaviour parallelling that of other marine turtle species. This study refutes the myth that hawksbill turtles remain resident at reefs associated with their nesting beaches.

International Movements of Adult Female Hawksbill Turtles (Eretmochelys imbricata): First Results from the Caribbean's Marine Turtle Tagging Centre

2011 ◽  
Vol 10 (1) ◽  
pp. 18-25 ◽  
Author(s):  
Julia A. Horrocks ◽  
Barry H. Krueger ◽  
Marina Fastigi ◽  
Emile L. Pemberton ◽  
Karen L. Eckert
Keyword(s):  
Adult Female ◽  
Marine Turtle ◽  
Eretmochelys Imbricata ◽  
First Results ◽  
Hawksbill Turtles

scholarly journals Shifting the life-history paradigm: discovery of novel habitat use by hawksbill turtles

2011 ◽  
Vol 8 (1) ◽  
pp. 54-56 ◽  
Author(s):  
Alexander R. Gaos ◽  
Rebecca L. Lewison ◽  
Ingrid L. Yañez ◽  
Bryan P. Wallace ◽  
Michael J. Liles ◽  
...  
Keyword(s):  
Life History ◽  
Habitat Use ◽  
Eastern Pacific ◽  
Life History Strategies ◽  
Evolutionary Trajectory ◽  
Eretmochelys Imbricata ◽  
Management Perspective ◽  
Novel Habitat ◽  
Marine Wildlife ◽  
Hawksbill Turtles

Adult hawksbill turtles ( Eretmochelys imbricata ) are typically described as open-coast, coral reef and hard substrate dwellers. Here, we report new satellite tracking data on female hawksbills from several countries in the eastern Pacific that revealed previously undocumented behaviour for adults of the species. In contrast to patterns of habitat use exhibited by their Caribbean and Indo-Pacific counterparts, eastern Pacific hawksbills generally occupied inshore estuaries, wherein they had strong associations with mangrove saltwater forests. The use of inshore habitats and affinities with mangrove saltwater forests presents a previously unknown life-history paradigm for adult hawksbill turtles and suggests a potentially unique evolutionary trajectory for the species. Our findings highlight the variability in life-history strategies that marine turtles and other wide-ranging marine wildlife may exhibit among ocean regions, and the importance of understanding such disparities from an ecological and management perspective.

Serum testosterone and estradiol-17ß levels during the peak period in a year-round Hawksbill Turtle Eretmochelys imbricata L. nesting population

2007 ◽  
Vol 13 (3) ◽  
pp. 151 ◽  
Author(s):  
K. A. Dobbs ◽  
J. D. Miller ◽  
D. W. Owens ◽  
A. M. Landry Jr.
Keyword(s):  
Austral Summer ◽  
Serum Testosterone ◽  
Marine Turtle ◽  
Gonadal Hormone ◽  
Future Research ◽  
Hormone Concentration ◽  
Peak Period ◽  
Eretmochelys Imbricata ◽  
Hawksbill Turtles ◽  
Nesting Season

Serum testosterone (T) and estradiol-17� (E2 ) concentrations were determined for 95 Hawksbill Turtles Eretmochelys imbricate nesting at Milman Island, northern Great Barrier Reef, Australia. This information describes gonadal hormone concentration during the Austral summer months for peak nesting in an E. imbricata population that nest year-round. A total of 173 samples was collected from 95 turtles, with 39 turtles sampled sequentially within their nesting cycle (n = 117 samples) and the remainder sampled at random. E2 -levels were measured from seven turtles sampled sequentially within their nesting cycle (n = 31 samples). T-Ievels ranged from 0 to 7 520 pg/ml; E2-Ieveis varied between 0.0 and 119.0 pg/ml. Peak T-Ievels in turtles sampled sequentially within their nesting cycle occurred after laying clutch number two or three while E2-levels peaked after clutch number one or two; levels of both hormones decreased thereafter. T- and E2-levels decreased monthly (December to March) within a nesting season. Based on T-Ievels, the greatest proportion (58%) of turtles began their nesting cycle in December. Turtles in the middle of their nesting cycle were found in equal proportions (27?35%) throughout the Austral summer months. Turtles at the end of their nesting cycle were most frequent (61%) in March. The implications of these results for future research and for managing access to islands with year-round marine turtle nesting are discussed.

scholarly journals Hematology, biochemistry, and toxicology of wild hawksbill turtles (Eretmochelys imbricata) nesting in mangrove estuaries in the eastern Pacific Ocean

2017 ◽  
Author(s):  
Aubrey M. Tauer ◽  
Michael J. Liles ◽  
Sofía Chavarría ◽  
Melissa Valle ◽  
Sada Amaya ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Pacific Ocean ◽  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Sea Turtle ◽  
Eastern Pacific ◽  
Eastern Pacific Ocean ◽  
Eretmochelys Imbricata ◽  
Mangrove Estuary ◽  
Hawksbill Turtles

AbstractSea turtles are a keystone species and are highly sensitive to changes in their environment, making them excellent environmental indicators. In light of environmental and climate changes, species are increasingly threatened by pollution, changes in ocean health, habitat alteration, and plastic ingestion. There may be additional health related threats and understanding these threats is key in directing future management and conservation efforts, particularly for severely reduced sea turtle populations. Hawksbill turtles (Eretmochelys imbricata) are critically endangered, with those in the eastern Pacific Ocean (Mexico–Peru) considered one of the most threatened sea turtle populations in the world. This study establishes baseline health parameters in hematology and blood biochemistry as well as tested for heavy metals and persitent organic pollutants in eastern Pacific hawksbills at a primary nesting colony located in a mangrove estuary. Whereas hematology and biochemistry results are consistent with healthy populations of other species of sea turtles, we identified differences in packed cell volume, heterophils and lympohcyte counts, and glucose when comparing our data to other adult hawksbill analysis (1), (2), (3). Our analysis of heavy metal contamination revealed a mean blood level of 0.245 ppm of arsenic, 0.045 ppm of lead, and 0.008 ppm of mercury. Blood levels of persistent organic pollutants were below the laboratory detection limit for all turtles. Our results suggest that differences in the feeding ecology of eastern Pacific hawksbills in mangrove estuaries may make them less likely to accumulate persistent organic pollutants and heavy metals in their blood. These baseline data on blood values in hawksbills nesting within a mangrove estuary in the eastern Pacific offer important guidance for health assessments of the species in the wild and in clinical rehabilitation facilities, and underscore the importance of preventing contamination from point and non-point sources in mangrove estuaries, which represent primary habitat to hawksbills and myriad other marine species in the eastern Pacific Ocean.

scholarly journals An assessment of the marine turtle fishery in Grenada, West Indies

Oryx ◽  
2007 ◽  
Vol 41 (3) ◽  
pp. 330-336 ◽  
Author(s):  
S. Grazette ◽  
J.A. Horrocks ◽  
Paul E. Phillip ◽  
Crafton J. Isaac
Keyword(s):  
Breeding Season ◽  
Landing Site ◽  
Chelonia Mydas ◽  
Marine Turtle ◽  
Catch Per Unit Effort ◽  
Eretmochelys Imbricata ◽  
Green Turtles ◽  
Hawksbill Turtles ◽  
Relative Scarcity ◽  
Made In

AbstractThe marine turtle fishery of Grenada was assessed using interviews with marine turtle fishermen and by examination of turtle catch data from a major landing site. An estimated 782 turtles, mainly Endangered green turtles Chelonia mydas and Critically Endangered hawksbill turtles Eretmochelys imbricata, were caught around Grenada and its sister island Carriacou each year between 1996 and 2001 during an annual 8-month open season, with only a small percentage being officially recorded at a landing site. Turtles were primarily caught with nets and spearguns, with more green turtles caught by net fishermen and more hawksbill turtles by spear fishermen. Catch per unit effort data suggested that relative abundance had declined since the previous estimate was made in 1969. Few adult green or loggerhead turtles Caretta caretta were caught, indicating the relative scarcity of this size class of these two species around Grenada. Adult-sized hawksbill turtles were caught regularly, with larger adults being caught in the non-breeding months of the open season than in the breeding months. A higher percentage of adult hawksbill turtles present during the breeding season are likely to be animals that nest in Grenada, and their smaller size may result from historically heavy fishing pressure. The larger sized adults caught during the non-breeding season are likely to be animals that forage around Grenada but breed elsewhere in the Caribbean where they are protected.

scholarly journals The importance of north-west Madagascar for marine turtle conservation

Oryx ◽  
2007 ◽  
Vol 41 (2) ◽  
pp. 232-238 ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document