Estimating the sex ratio of green sea turtles (Chelonia mydas) in Taiwan by the nest temperature and histological methods

King, Rowena; Cheng, Wan‐Hwa; Tseng, Cheng-Tsung; Chen, Hochang; Cheng, I-Jiunn

doi:10.1016/j.jembe.2013.03.016

Cited by 34 publications

(21 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We used a one‐ to four‐day correction factor for the hatching‐to‐emergence interval in overall hatchling sex ratio calculations to establish a range of mean values that accounts for potential differences in the amount of time it takes a hatchling to emerge from the nest after hatching, which would affect incubation duration estimates (Godfrey et al, ; Godfrey & Mrosovsky, ). We calculated the overall sex ratio for each protection strategy within and across sites, and among years, and for specific comparisons among nest protection strategies and between sites, we used a three‐day correction factor based on nests that showed a marked temperature signal at hatching (mean = 2.9 ± 0.2 days, n = 3; King, Cheng, Tseng, Chen, & Cheng, ).…”

Section: Methodsmentioning

confidence: 99%

Potential limitations of behavioral plasticity and the role of egg relocation in climate change mitigation for a thermally sensitive endangered species

Liles

Peterson

Seminoff

et al. 2019

Ecology and Evolution

View full text Add to dashboard Cite

Anthropogenic climate change is widely considered a major threat to global biodiversity, such that the ability of a species to adapt will determine its likelihood of survival. Egg‐burying reptiles that exhibit temperature‐dependent sex determination, such as critically endangered hawksbill turtles ( Eretmochelys imbricata ), are particularly vulnerable to changes in thermal regimes because nest temperatures affect offspring sex, fitness, and survival. It is unclear whether hawksbills possess sufficient behavioral plasticity of nesting traits (i.e., redistribution of nesting range, shift in nesting phenology, changes in nest‐site selection, and adjustment of nest depth) to persist within their climatic niche or whether accelerated changes in thermal conditions of nesting beaches will outpace phenotypic adaption and require human intervention. For these reasons, we estimated sex ratios and physical condition of hatchling hawksbills under natural and manipulated conditions and generated and analyzed thermal profiles of hawksbill nest environments within highly threatened mangrove ecosystems at Bahía de Jiquilisco, El Salvador, and Estero Padre Ramos, Nicaragua. Hawksbill clutches protected in situ at both sites incubated at higher temperatures, yielded lower hatching success, produced a higher percentage of female hatchlings, and produced less fit offspring than clutches relocated to hatcheries. We detected cooler sand temperatures in woody vegetation (i.e., coastal forest and small‐scale plantations of fruit trees) and hatcheries than in other monitored nest environments, with higher temperatures at the deeper depth. Our findings indicate that mangrove ecosystems present a number of biophysical (e.g., insular nesting beaches and shallow water table) and human‐induced (e.g., physical barriers and deforestation) constraints that, when coupled with the unique life history of hawksbills in this region, may limit behavioral compensatory responses by the species to projected temperature increases at nesting beaches. We contend that egg relocation can contribute significantly to recovery efforts in a changing climate under appropriate circumstances.

show abstract

Section: Methodsmentioning

confidence: 99%

Potential limitations of behavioral plasticity and the role of egg relocation in climate change mitigation for a thermally sensitive endangered species

Liles

Peterson

Seminoff

et al. 2019

Ecology and Evolution

View full text Add to dashboard Cite

show abstract

“…There are three nesting sites for green turtles in Taiwan; namely Wan-an Island of Penghu Archipelago, Lanyu Island of Taitung County, and LiuChiu Island of Pentung County (King et al, 2013). Chen et al (2010) determined the change of oxygen content during embryogenesis of green turtles on Wan-an and identified the major influential factors.…”

Section: Introductionmentioning

confidence: 99%

Factors influencing variations of oxygen content in nests of green sea turtles during egg incubation with a comparison of two nesting environments

Cheng

Lin

Tseng

2015

Journal of Experimental Marine Biology and Ecology

Self Cite

View full text Add to dashboard Cite

“…Artificially hatched eggs of oblong rockfish, Sebastes oblongus at 18°C were all females from the experiment ( Kwak et al, 2006 ). Genetical factors and environmental factors determine physiological sex of vertebrate animals like reptiles and vertebrate fish ( Pieau et al, 1994 ), and the water temperature is known to be one of the most influential factors ( Lang & Andrews, 1994 ; Baras et al, 2001 ; King et al, 2013 ).…”

Section: Discussionmentioning

confidence: 99%

Spawning Characteristics and Artificial Hatching of Female Mottled Skate, Beringraja pulchra in the West Coast of Korea

Kang¹,

Jo²,

Kang³

et al. 2013

Development &Amp; Reproduciton

View full text Add to dashboard Cite

The gonadsomatic index (GSI) of mottled skate was the highest in April, GSI and HSI showed a reverse phase for its reproductive cycle. The fish had one pair of egg capsules, having 1 to 7 fertilized eggs, and spawned all the year round. When surveying the reproductive characteristics of females over 63 ㎝ in disc width, we found the spawning peak was between April to June, and the appearance ratio of egg capsules was the highest in May (32.1%). The eggs were hatched at 8°C, 13°C, 18°C, water temperature (12.8 to 24.2°C), and the best hatching temperature was 18°C. The number of fish hatched was 4 to 5 fish/egg capsules, and the hatching rate was 100%. The sex ratios of hatching larvae were 45.5% female and 54.5% male. Therefore this study will provide fundamental data and information for artificial reproduction of the mottled skate.

show abstract

Estimating the sex ratio of green sea turtles (Chelonia mydas) in Taiwan by the nest temperature and histological methods

Cited by 34 publications

References 41 publications

Potential limitations of behavioral plasticity and the role of egg relocation in climate change mitigation for a thermally sensitive endangered species

Potential limitations of behavioral plasticity and the role of egg relocation in climate change mitigation for a thermally sensitive endangered species

Factors influencing variations of oxygen content in nests of green sea turtles during egg incubation with a comparison of two nesting environments

Spawning Characteristics and Artificial Hatching of Female Mottled Skate, Beringraja pulchra in the West Coast of Korea

Contact Info

Product

Resources

About