Body Mass and the Energy Budget of Gravid Hawksbill Turtles (Eretmochelys imbricata) during the Nesting Season

2010 ◽  
Vol 44 (3) ◽  
pp. 352-359 ◽  
Author(s):  
Armando J. B. Santos ◽  
Eliza M. X. Freire ◽  
Claudio Bellini ◽  
Gilberto Corso
Keyword(s):  
Body Mass ◽  
Energy Budget ◽  
Eretmochelys Imbricata ◽  
Hawksbill Turtles ◽  
Nesting Season

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 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 Nesting ecology of hawksbill turtles, Eretmochelys imbricata, in an extreme environmental setting

PLoS ONE ◽  
2018 ◽  
Vol 13 (9) ◽  
pp. e0203257 ◽  
Author(s):  
Mark Chatting ◽  
David Smyth ◽  
Ibrahim Al-Maslamani ◽  
Jeffrey Obbard ◽  
Mehsin Al-Ansi ◽  
...  
Keyword(s):  
Nesting Ecology ◽  
Eretmochelys Imbricata ◽  
Environmental Setting ◽  
Hawksbill Turtles

Single nucleotide polymorphism markers for genotyping hawksbill turtles (Eretmochelys imbricata)

2019 ◽  
Vol 12 (3) ◽  
pp. 353-356
Author(s):  
Shreya M. Banerjee ◽  
Lisa M. Komoroske ◽  
Amy Frey ◽  
Brittany Hancock-Hanser ◽  
Phillip A. Morin ◽  
...  
Keyword(s):  
Single Nucleotide Polymorphism ◽  
Nucleotide Polymorphism ◽  
Single Nucleotide ◽  
Eretmochelys Imbricata ◽  
Hawksbill Turtles

scholarly journals Ascension Island as a mid-Atlantic developmental habitat for juvenile hawksbill turtles

2014 ◽  
Vol 97 (4) ◽  
pp. 813-820 ◽  
Author(s):  
Sam B. Weber ◽  
Nicola Weber ◽  
Brendan J. Godley ◽  
Tara Pelembe ◽  
Stedson Stroud ◽  
...  
Keyword(s):  
Benthic Algae ◽  
Chelonia Mydas ◽  
Small Population ◽  
Future Research ◽  
Home Ranges ◽  
Utilization Distribution ◽  
Eretmochelys Imbricata ◽  
Ascension Island ◽  
Minimum Residence Time ◽  
Hawksbill Turtles

Ascension Island in the South Atlantic Ocean is renowned for its globally-important nesting population of green turtles (Chelonia mydas) that has been the subject of long-term research. By comparison, very little is known about the apparently small population of hawksbill turtles (Eretmochelys imbricata) that have been recorded in its waters, thousands of kilometres from known nesting beaches. Here, we collate 10 years of in-water tagging data, opportunistic public sighting records and underwater observations to provide a baseline for future research, and present preliminary data on habitat use derived from two individuals fitted with GPS transmitters. Although public sightings were inevitably biased towards popular recreation areas, the resulting distribution suggests that hawksbill turtles occur year round in Ascension Island's waters along the entire 65 km of coastline. Hawksbills were observed feeding on benthic algae and encrusting sponges, and were frequently seen scavenging on fish discards around the Island's pier at night aided by anthropogenic lighting. Between 2003 and 2013, 35 turtles were captured, measured, tagged and then released. Curved carapace lengths ranged from 33.5 to 85 cm (mean = 48.8 cm) indicating that most (if not all) individuals encountered around Ascension are post-pelagic juveniles. Four individuals were recaptured at least once giving a mean minimum residence time of 4.2 yr (range: 2.8–7.3 yr) and a mean growth rate of 2.8 cm yr−1. Turtles fitted with Fastloc™ GPS devices remained at Ascension Island for the duration of the study (>90 days) and occupied restricted home ranges with an average area of 2.5 km2 and an average ‘core use area’ (50% utilization distribution) of 0.05 km2. Together, these results suggest that Ascension Island serves as a mid-Atlantic developmental habitat for benthic-feeding, juvenile hawksbill turtles on extended oceanic migrations before recruiting to their adult foraging grounds, likely to be located in Brazil or tropical West Africa.

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