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Santidrián Tomillo P, Cordero-Umaña K, Valverde-Cantillo V. High thermal tolerance of egg clutches and potential adaptive capacity in green turtles. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 952:175961. [PMID: 39226957 DOI: 10.1016/j.scitotenv.2024.175961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2024] [Revised: 08/29/2024] [Accepted: 08/30/2024] [Indexed: 09/05/2024]
Abstract
Climate warming threatens sea turtles, among other effects, because high temperatures increase embryo mortality. However, not all species and populations are expected to respond the same way because they could have different thermal tolerances and capacities to adapt. We tested the effect of incubation temperature on egg mortality in a population of green turtles (Chelonia mydas) previously suggested to be less affected by extreme climatic events than others. We (1) assessed the relationship between temperature and hatching success, (2) defined an optimal range of temperatures that maximized hatching success and (3) assessed the variability in the response to temperature among clutches laid by different mothers, which could allow adaptation. Hatching success was consistently high in green turtle clutches with a skew toward high values, with 50 % of clutches having a success above 94 %. Yet, it was mildly affected by temperature, declining at both low and high temperatures. The optimal range of mean incubation temperatures was between ~30.5 °C and 32.5 °C. Current mean temperatures (31.3 °C) fall within the middle of the optimal range, indicating a potential resilience to further rises in mean nest temperature. Hatching success was best described by nest temperature and the interaction between female identity and temperature. This last predictor indicated a variability in thermal tolerance among clutches laid by different mothers and therefore, a capacity to adapt. The studied population of green turtles seems to be less vulnerable than others to climate warming. Understanding how different populations could respond to increasing temperatures could help complete the picture on the potential effects of climate change on sea turtles.
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Affiliation(s)
- Pilar Santidrián Tomillo
- Centre Oceanogràfic de les Balears, Instituto Español de Oceanografía (IEO, CSIC), Moll de Ponent s/n, 07015 Palma de Mallorca, Spain.
| | - Keilor Cordero-Umaña
- The Leatherback Trust, Goldring-Gund Marine Biology Station, Playa Grande, Costa Rica; Menéndez Pelayo International University (UIMP-CSIC), Isaac Peral 23, 28040 Madrid, Spain
| | - Verónica Valverde-Cantillo
- The Leatherback Trust, Goldring-Gund Marine Biology Station, Playa Grande, Costa Rica; Escuela de Biología, Universidad de Costa Rica, San José, Costa Rica
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Kynoch C, Paladino FV, Spotila JR, Santidrián Tomillo P. Variability in thermal tolerance of clutches from different mothers indicates adaptation potential to climate warming in sea turtles. GLOBAL CHANGE BIOLOGY 2024; 30:e17447. [PMID: 39098999 DOI: 10.1111/gcb.17447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 06/19/2024] [Accepted: 07/02/2024] [Indexed: 08/06/2024]
Abstract
The current climate warming is a challenge to biodiversity that could surpass the adaptation capacity of some species. Hence, understanding the means by which populations undergo an increase in their thermal tolerance is critical to assess how they could adapt to climate warming. Specifically, sea turtle populations could respond to increasing temperatures by (1) colonizing new nesting areas, (2) nesting during cooler times of the year, and/or (3) by increasing their thermal tolerance. Differences in thermal tolerance of clutches laid by different females would indicate that populations have the potential to adapt by natural selection. Here, we used exhaustive information on nest temperatures and hatching success of leatherback turtle (Dermochelys coriacea) clutches over 14 years to assess the occurrence of individual variability in thermal tolerance among females. We found an effect of temperature, year, and the interaction between female identity and nest temperature on hatching success, indicating that clutches laid by different females exhibited different levels of vulnerability to high temperatures. If thermal tolerance is a heritable trait, individuals with higher thermal tolerances could have greater chances of passing their genes to following generations, increasing their frequency in the population. However, the high rate of failure of clutches at temperatures above 32°C suggests that leatherback turtles are already experiencing extreme heat stress. A proper understanding of mechanisms of adaptation in populations to counteract changes in climate could greatly contribute to future conservation of endangered populations in a rapidly changing world.
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Affiliation(s)
- Camille Kynoch
- Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, Florida, USA
| | - Frank V Paladino
- The Leatherback Trust, Goldring-Gund Marine Biology Station, Playa Grande, Costa Rica
- Department of Biology, Purdue University Fort Wayne, Fort Wayne, Indiana, USA
| | - James R Spotila
- The Leatherback Trust, Goldring-Gund Marine Biology Station, Playa Grande, Costa Rica
- Department of Biodiversity, Earth and Environmental Science, Drexel University, Philadelphia, Pennsylvania, USA
| | - Pilar Santidrián Tomillo
- Centre Oceanogràfic de les Balears, Instituto Español de Oceanografía (IEO, CSIC), Palma de Mallorca, Spain
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Robledo-Avila LA, Phillips-Farfán BV, García-Bucio IY, Montes-Sánchez S, Herrera-Vargas MA, Contreras-Garduño J, Núñez-Anita RE, Martínez-Lendech N, Meléndez-Herrera E. Incubation in shaded hatcheries biases sex-determination but preserves Lepidochelys olivacea hatchling physiology. MARINE ENVIRONMENTAL RESEARCH 2023; 192:106244. [PMID: 37924794 DOI: 10.1016/j.marenvres.2023.106244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 09/29/2023] [Accepted: 10/24/2023] [Indexed: 11/06/2023]
Abstract
Some studies have associated ex situ conservation with cerebral and gonadal developmental delay, as well as decreased motor performance in Lepidochelys olivacea offspring. Ex situ management is also related to a more mature spleen and a differential leukocyte count in newly emerged Lepidochelys olivacea hatchlings. The physiological relevance of a more mature spleen is unknown in sea turtles, but studies in birds suggest an increased immune response. Because egg relocation to hatcheries is a common conservation practice, it is imperative to know its impact on hatchling physiology. Herein, plasma activity of superoxide dismutase, alkaline phosphatase and the alternative complement pathway, as well as total antioxidant capacity and hydrogen peroxide concentrations were quantified in hatchlings from in situ and ex situ nests under basal conditions at nest emergence. Toll-like receptor 4 (tlr4), heat shock proteins (hsp) 70 and hsp90 expression were quantified in the spleen and liver of the hatchlings. Hepatocyte density and nuclear area were quantified in histological sections of the liver and all turtles were sexed by histological sectioning of the gonads. Total antioxidant capacity and hydrogen peroxide concentrations in plasma were lower in turtles from ex situ nests, while tlr4 and hsp70 mRNA expression was higher in the spleen but not in the liver. Ex situ incubation produced 98% male hatchlings, whereas in situ incubation produced 100% females. There were no other differences in the attributes sampled between hatchlings emerging from ex situ and in situ treatments. The results suggest that ex situ relocated turtles may be less prone to oxidative stress than in situ incubated hatchlings and could have more mature splenic function. Together, the data suggest that ex situ relocation to shaded hatcheries biased sex determination but preserved the general physiological condition of sea turtle hatchlings.
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Affiliation(s)
- Liliana Areli Robledo-Avila
- Instituto de Investigaciones sobre Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Av. San Juanito Itzícuaro s/n, Colonia Nueva Esperanza, C.P. 58337, Morelia, Michoacán, Mexico.
| | - Bryan Víctor Phillips-Farfán
- Laboratorio de Nutrición Experimental, Instituto Nacional de Pediatría, Insurgentes Sur 3700, Letra C, Alcaldía Coyoacán, C.P. 04530, Cd. de México, Mexico.
| | - Irma Yunuen García-Bucio
- Instituto de Investigaciones sobre Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Av. San Juanito Itzícuaro s/n, Colonia Nueva Esperanza, C.P. 58337, Morelia, Michoacán, Mexico.
| | - Shannen Montes-Sánchez
- Instituto de Investigaciones sobre Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Av. San Juanito Itzícuaro s/n, Colonia Nueva Esperanza, C.P. 58337, Morelia, Michoacán, Mexico.
| | - Ma Antonia Herrera-Vargas
- Instituto de Investigaciones sobre Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Av. San Juanito Itzícuaro s/n, Colonia Nueva Esperanza, C.P. 58337, Morelia, Michoacán, Mexico.
| | - Jorge Contreras-Garduño
- Escuela Nacional de Estudios Superiores, Unidad Morelia, Universidad Nacional Autónoma de México, Antigua Carretera a Pátzcuaro 8701, Ex-Hacienda de San José de la Huerta, 58190, Morelia, Michoacán, Mexico.
| | - Rosa Elvira Núñez-Anita
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, 58130, Morelia, Michoacán, Mexico.
| | - Norma Martínez-Lendech
- Escuela Nacional de Estudios Superiores, Unidad Morelia, Universidad Nacional Autónoma de México, Antigua Carretera a Pátzcuaro 8701, Ex-Hacienda de San José de la Huerta, 58190, Morelia, Michoacán, Mexico.
| | - Esperanza Meléndez-Herrera
- Instituto de Investigaciones sobre Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Av. San Juanito Itzícuaro s/n, Colonia Nueva Esperanza, C.P. 58337, Morelia, Michoacán, Mexico.
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Sosa-Cornejo I, Martín-Del-Campo R, González-Flores JA, González-Camacho ZB, Cabrera-Cuellar BA, Bielli A, Valdes-Flores JE, Olimón-Andalón V. Leucism: the prevalent congenital malformation in the olive ridley sea turtle of northwestern Mexico. DISEASES OF AQUATIC ORGANISMS 2022; 152:61-71. [PMID: 36394141 DOI: 10.3354/dao03705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Despite being the most abundant sea turtle in the world, the olive ridley turtle Lepidochelys olivacea is classified as Vulnerable by the IUCN. There is evidence of congenital malformations in hatchlings, and the associated causes are multifactorial, with both genetic and environmental sources. Santuario Playa Ceuta (SPC) is a sanctuary for the olive ridley, located at the northernmost region of its nesting range in the Mexican Pacific. The objective of this study was to identify and quantify the prevalence and severity of congenital malformations in olive ridley embryos/hatchlings in SPC during the 2017 nesting season. We collected 62907 eggs from 643 relocated nests that were moved to a hatchery, of which 4242 eggs with obvious development did not hatch and were analyzed for this study. Hatching success was 53.9%, with 22.5% of nests (n = 145) and 0.54% of eggs (n = 344) showing embryos or hatchlings with malformations. The nest severity index was 2.4 (range: 1-10) malformed embryos or hatchlings per nest, and the organism severity index was 1.4 (range: 1-7) malformations per malformed embryo or hatchling. Leucism was the most prevalent malformation (34.4%; 170/494 total observed), with the craniofacial region showing the greatest diversity of malformations (17/35 types). Given the geographical position of SPC, extreme environmental conditions (e.g. cold, heat, and dryness) could be one of the main causes of teratogenesis in this species. However, more studies are needed regarding the presence of contaminants, genetic factors, health assessments of nesting females, and malformation rates of nests that remain in situ versus those that are relocated.
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Affiliation(s)
- Ingmar Sosa-Cornejo
- Doctorado en Ciencias Biológicas, Facultad de Biología, Universidad Autónoma de Sinaloa, Culiacán, Sinaloa 80040, Mexico
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Salleh SM, Sah SAM, Chowdhury AJK, Chowdhury AJK. The Survival Rate from Splitting Clutch Design Method for Green Turtle's Relocated Nest in Penang Island, Malaysia. Trop Life Sci Res 2022; 33:107-127. [PMID: 36545050 PMCID: PMC9747109 DOI: 10.21315/tlsr2022.33.3.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Ten nests were collected from Kerachut and Teluk Kampi, Penang Island between 2 August 2009 and 9 December 2009, and each one nest was split into three small clutch sizes for incubation at three nesting depths (45 cm, 55 cm and 65 cm), with a total of 30 modified nests for this experiment. Three important objectives were formulated; to observe on the survival hatchings among the three nesting depths, to study on the effects of sand temperature on incubation period among the three nesting depths, and to investigate the influence of sand temperature on hatchling's morphology. Main result shows that the mean survival of the hatchlings was 25.40% at 45 cm nesting depth, followed by mean 17.60% at 55 cm nesting depth, and lastly, the mean was 21.50% at 65 cm nesting depth. Overall, there are 56.63% survival hatchlings, 10.97% dead hatchlings and 32.40% unhatched eggs were produced. The incubation period was also found to be significantly correlated with sand temperature, p > 0.001, and nesting depth, p < 0.001. The hatchling's length and weight varies is sizes across the nesting depths, p < 0.001. However, the small difference in hatchling sizes per nesting depths are not strong enough to prove the significant correlation with sand temperature, p > 0.05. This article provides a basic knowledge from the splitting clutch design method. A sum of 50%-60% survivals hatchlings produced were incubating under small range of clutch sizes, 29 to 49 eggs. This article provides basic result on the survival hatchlings, eggs survivorship, incubation period, temperature, hatchling's morphology and discussion on implication of this method on conservation in Malaysia.
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Affiliation(s)
- Sarahaizad Mohd Salleh
- School of Biological Sciences, Universiti Sains Malaysia, 11800 USM Pulau Pinang, Malaysia,Corresponding author: ;
| | - Shahrul Anuar Mohd Sah
- School of Biological Sciences, Universiti Sains Malaysia, 11800 USM Pulau Pinang, Malaysia,Corresponding author: ;
| | - Ahmed Jalal Khan Chowdhury
- Faculty of Agriculture, Universiti Islam Sultan Sharif Ali, Simpang 347 Jalan Pasar Gadong, BE1310 Brunei Darussalam
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Adams DM, Williamson SA, Evans RG, Reina RD. Increasing hypoxia progressively slows early embryonic development in an oviparous reptile, the green turtle, Chelonia mydas. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220709. [PMID: 36061518 PMCID: PMC9428527 DOI: 10.1098/rsos.220709] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 08/12/2022] [Indexed: 06/15/2023]
Abstract
Green turtle (Chelonia mydas) embryos are in an arrested state of development when the eggs are laid, but in the presence of oxygen, arrest is broken and development resumes within 12-16 h. However, the precise oxygen level at which embryos break arrest and continue development is not known. To better understand the impact of oxygen concentration on breaking of arrest and early embryonic development, we incubated freshly laid eggs of the green sea turtle for three days at each of six different oxygen concentrations (less than or equal to 1%, 3%, 5%, 7%, 9% and 21%) and monitored the appearance and growth of white spots on the shell, indicative of embryonic development. As reported previously, white spots did not develop on eggs incubated in anoxia (less than or equal to 1% oxygen). For all other treatments, mean time to white spot detection and white spot growth rate varied inversely with oxygen concentration. In nearly all cases the difference between eggs at different oxygen levels was statistically significant (p ≤ 0.05). This suggests that sea turtle embryonic development may respond to oxygen in a dose-dependent manner. Our results indicate that the development of green turtle embryos may be slowed if they are exposed to the most hypoxic conditions reported in mature natural nests.
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Affiliation(s)
| | | | - Roger G. Evans
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria 3800, Australia
- Pre-clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria 3010, Australia
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Tanabe LK, Ellis J, Elsadek I, Berumen ML. Potential feminization of Red Sea turtle hatchlings as indicated by in situ sand temperature profiles. CONSERVATION SCIENCE AND PRACTICE 2020. [DOI: 10.1111/csp2.266] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Lyndsey K. Tanabe
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering King Abdullah University of Science and Technology Thuwal Saudi Arabia
| | - Joanne Ellis
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering King Abdullah University of Science and Technology Thuwal Saudi Arabia
- School of Biological Sciences Waikato University Tauranga New Zealand
| | - Islam Elsadek
- Egyptian Environmental Affairs Agency, Ministry of Environment Hurghada Egypt
| | - Michael L. Berumen
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering King Abdullah University of Science and Technology Thuwal Saudi Arabia
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Staines MN, Booth DT, Limpus CJ. Microclimatic effects on the incubation success, hatchling morphology and locomotor performance of marine turtles. ACTA OECOLOGICA 2019. [DOI: 10.1016/j.actao.2019.04.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Optimism for mitigation of climate warming impacts for sea turtles through nest shading and relocation. Sci Rep 2018; 8:17625. [PMID: 30514853 PMCID: PMC6279794 DOI: 10.1038/s41598-018-35821-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 11/09/2018] [Indexed: 11/08/2022] Open
Abstract
Increasing incubation temperatures may threaten the viability of sea turtle populations. We explored opportunities for decreasing incubation temperatures at a Caribbean rookery with extreme female-biased hatchling production. To investigate the effect of artificial shading, temperatures were measured under simple materials (white sheet, white sand, palm leaves). To test natural drivers of incubation temperature, temperatures were measured at average nest depths with shading on two beaches. Results from a pilot experiment suggest the most effective material was palm leaves. Shading decreased temperatures by a mean of 0.60 °C (SE = 0.10 °C, N = 20). Variation between beaches averaged 1.88 °C (SE = 0.13 °C, N = 20). We used long-term rookery data combined with experimental data to estimate the effect on sex ratio: relocation and shading could shift ratios from current ranges (97–100% female) to 60–90% female. A conservation mitigation matrix summarises our evidence that artificial shading and nest relocation are effective, low-cost, low-technology conservation strategies to mitigate impacts of climate warming for sea turtles.
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Booth DT. Incubation temperature induced phenotypic plasticity in oviparous reptiles: Where to next? JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2018; 329:343-350. [DOI: 10.1002/jez.2195] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 05/17/2018] [Accepted: 05/18/2018] [Indexed: 11/10/2022]
Affiliation(s)
- David T. Booth
- School of Biological Sciences; The University of Queensland; Queensland Australia
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Booth DT, Dunstan A. A preliminary investigation into the early embryo death syndrome (EEDS) at the world's largest green turtle rookery. PLoS One 2018; 13:e0195462. [PMID: 29694365 PMCID: PMC5918617 DOI: 10.1371/journal.pone.0195462] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/22/2018] [Indexed: 11/19/2022] Open
Abstract
Raine Island hosts the largest nesting aggregation of green turtles in the world, but nest emergence success and hence recruitment of hatchlings off the beach appear to have significantly declined since the 1990s. Nests destroyed by subsequent nesting turtles, and nest failure due to flooding account for most of the nest failure, but many nests still have poor hatch success even when undisturbed and flood-free. In undisturbed, flood-free nests that experience high mortality, embryos typically die at a very early stage of development, a phenomenon we term early embryo death syndrome (EEDS). Previous research indicates that EEDS is correlated with the number of females nesting at Raine Island during a nesting season. Here, we monitor nest temperature and oxygen (PO2) and carbon dioxide (PCO2) partial pressures during the first week after nest construction to discover if they are associated with EEDS. Our investigation found that the proportion of early embryo death was greatest in two nests that experienced the highest nest temperature, lowest PO2 and highest PCO2 during the first week of incubation suggesting that these variables either by themselves or in combination may be the underlying cause of EEDS. These two nests were located adjacent to maturing nests, so the high temperature and more extreme PO2s and PCO2s are most likely to be caused by the combined metabolism of embryos in the mature nests. Although this conclusion is based on just two nests and needs to be substantiated in future studies, it would appear that the laying of new nests in the close location to mature nests could be a significant cause of hatch failure at high density nesting sea turtle rookeries around the world.
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Affiliation(s)
- David Terrington Booth
- School of Biological Sciences, The University of Queensland, Queensland, Australia
- * E-mail:
| | - Andrew Dunstan
- Queensland Government Department of National Parks, Sports and Racing, Brisbane, Queensland, Australia
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Read TC, Petit M, Magnan M, Booth D. Going back to the roots: finding a strategy for the management of nesting loggerhead sea turtles in New Caledonia. AUST J ZOOL 2018. [DOI: 10.1071/zo19051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Incubation temperature plays a vital role in sea turtle life history because it influences embryonic growth, sex determination and hatchling attributes such as body size, residual yolk size, self-righting ability, crawling speed and swimming speed. For these reasons there is concern that predicted increases in air temperature, as a result of global warming, will increase nest temperatures and result in decreased hatching success, decrease or cease male hatchling production, and decreased hatchling quality. In a previous study examining incubation temperature at a loggerhead turtle (Caretta caretta) rookery located at La Roche Percée, New Caledonia, high nest temperatures and root invasion by beach morning glory (Ipomoea pes-caprae) were found to adversely affect hatching success and locomotor performance. In the current study, we relocated loggerhead turtle nests into shaded hatcheries. Shading nests decreased sand and nest temperatures and was predicted to increase male hatchling production slightly, but nest emergence success was decreased due to invasion of cottonwood (Hibiscus tiliaceus) roots into some nests. Using shaded structures is a viable and affordable management option to counteract the high sand temperatures found on some sea turtle nesting beaches, but these shade structures need to be located some distance from trees and other plants to ensure that root penetration into nests does not adversely affect nest emergence success.
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Affiliation(s)
- Juan Lei
- School of Biological Science; The University of Queensland; Brisbane St. Lucia Queensland 4072 Australia
| | - David T. Booth
- School of Biological Science; The University of Queensland; Brisbane St. Lucia Queensland 4072 Australia
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Fuentes MM, Monsinjon J, Lopez M, Lara P, Santos A, dei Marcovaldi MA, Girondot M. Sex ratio estimates for species with temperature-dependent sex determination differ according to the proxy used. Ecol Modell 2017. [DOI: 10.1016/j.ecolmodel.2017.09.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Affiliation(s)
- David T. BOOTH
- School of Biological Sciences; The University of Queensland; St Lucia Queensland Australia
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Rees AF, Alfaro-Shigueto J, Barata PCR, Bjorndal KA, Bolten AB, Bourjea J, Broderick AC, Campbell LM, Cardona L, Carreras C, Casale P, Ceriani SA, Dutton PH, Eguchi T, Formia A, Fuentes MMPB, Fuller WJ, Girondot M, Godfrey MH, Hamann M, Hart KM, Hays GC, Hochscheid S, Kaska Y, Jensen MP, Mangel JC, Mortimer JA, Naro-Maciel E, Ng CKY, Nichols WJ, Phillott AD, Reina RD, Revuelta O, Schofield G, Seminoff JA, Shanker K, Tomás J, van de Merwe JP, Van Houtan KS, Vander Zanden HB, Wallace BP, Wedemeyer-Strombel KR, Work TM, Godley BJ. Are we working towards global research priorities for management and conservation of sea turtles? ENDANGER SPECIES RES 2016. [DOI: 10.3354/esr00801] [Citation(s) in RCA: 175] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Sim EL, Booth DT, Limpus CJ. Incubation temperature, morphology and performance in loggerhead (Caretta caretta) turtle hatchlings from Mon Repos, Queensland, Australia. Biol Open 2015; 4:685-92. [PMID: 26002933 PMCID: PMC4467188 DOI: 10.1242/bio.20148995] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Marine turtles are vulnerable to climate change because their life history and reproduction are tied to environmental temperatures. The egg incubation stage is arguably the most vulnerable stage, because marine turtle eggs require a narrow range of temperatures for successful incubation. Additionally, incubation temperature affects sex, emergence success, morphology and locomotor performance of hatchlings. Hatchlings often experience high rates of predation in the first few hours of their life, and increased size or locomotor ability may improve their chances of survival. Between 2010 and 2013 we monitored the temperature of loggerhead (Caretta caretta; Linnaeus 1758) turtle nests at Mon Repos Rookery, and used these data to calculate a mean three day maximum temperature (T3dm) for each nest. We calculated the hatching and emergence success for each nest, then measured the mass, size and locomotor performance of hatchlings that emerged from those nests. Nests with a T3dm greater than 34°C experienced a lower emergence success and produced smaller hatchlings than nests with a T3dm lower than 34°C. Hatchlings from nests with a T3dm below 34°C performed better in crawling and swimming trials than hatchlings from nests with a T3dm above 34°C. Thus even non-lethal increases in global temperatures have the potential to detrimentally affect fitness and survival of marine turtle hatchlings.
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Affiliation(s)
- Elizabeth L Sim
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - David T Booth
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Colin J Limpus
- Department of Environment and Heritage Protection, PO Box 2454, Brisbane, QLD 4001, Australia
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Fisher LR, Godfrey MH, Owens DW. Incubation temperature effects on hatchling performance in the loggerhead sea turtle (Caretta caretta). PLoS One 2014; 9:e114880. [PMID: 25517114 PMCID: PMC4269397 DOI: 10.1371/journal.pone.0114880] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 11/10/2014] [Indexed: 11/26/2022] Open
Abstract
Incubation temperature has significant developmental effects on oviparous animals, including affecting sexual differentiation for several species. Incubation temperature also affects traits that can influence survival, a theory that is verified in this study for the Northwest Atlantic loggerhead sea turtle (Caretta caretta). We conducted controlled laboratory incubations and experiments to test for an effect of incubation temperature on performance of loggerhead hatchlings. Sixty-eight hatchlings were tested in 2011, and 31 in 2012, produced from eggs incubated at 11 different constant temperatures ranging from 27°C to 33°C. Following their emergence from the eggs, we tested righting response, crawling speed, and conducted a 24-hour long swim test. The results support previous studies on sea turtle hatchlings, with an effect of incubation temperature seen on survivorship, righting response time, crawling speed, change in crawl speed, and overall swim activity, and with hatchlings incubated at 27°C showing decreased locomotor abilities. No hatchlings survived to be tested in both years when incubated at 32°C and above. Differences in survivorship of hatchlings incubated at high temperatures are important in light of projected higher sand temperatures due to climate change, and could indicate increased mortality from incubation temperature effects.
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Affiliation(s)
- Leah R. Fisher
- University of Charleston South Carolina at the College of Charleston, Charleston, South Carolina, United States of America
- * E-mail:
| | - Matthew H. Godfrey
- North Carolina Wildlife Resources Commission, Beaufort, North Carolina, United States of America
- Duke University Marine Lab, Nicholas School of the Environment, Beaufort, North Carolina, United States of America
| | - David W. Owens
- University of Charleston South Carolina at the College of Charleston, Charleston, South Carolina, United States of America
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Howard R, Bell I, Pike DA. Thermal tolerances of sea turtle embryos: current understanding and future directions. ENDANGER SPECIES RES 2014. [DOI: 10.3354/esr00636] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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20
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Stubbs JL, Kearney MR, Whiting SD, Mitchell NJ. Models of primary sex ratios at a major flatback turtle rookery show an anomalous masculinising trend. ACTA ACUST UNITED AC 2014. [DOI: 10.1186/s40665-014-0003-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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21
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Read T, Booth DT, Limpus CJ. Effect of nest temperature on hatchling phenotype of loggerhead turtles (Caretta caretta) from two South Pacific rookeries, Mon Repos and La Roche Percée. AUST J ZOOL 2012. [DOI: 10.1071/zo12079] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
La Roche Percée, in New Caledonia, is the most important loggerhead turtle rookery outside of Australia for the eastern Pacific genetic stock. The females nesting on this beach are genetically similar to the females found at the Mon Repos rookery in Queensland, Australia. This study shows how nest temperature affects the phenotype of genetically similar populations. During the 2010–11 breeding season, mean nest temperatures were significantly higher at La Roche Percée (31.8°C) than at Mon Repos (29.5°C) and the mean for the three-days-in-a-row maximum nest temperatures was also significantly higher at La Roche Percée (34.6°C), than at Mon Repos (31.7°C). Differences were found in mean hatching success (La Roche Percée 83 ± 3%, Mon Repos 96 ± 2%) and emergence success (La Roche Percée 76 ± 3%, Mon Repos 93 ± 3%). Hatchlings from La Roche Percée also had significantly lower fitness characteristics, having smaller carapace size (La Roche Percée 1565 ± 7 mm2, Mon Repos 1634 ± 5 mm2), slower self-righting times (La Roche Percée 4.7 ± 0.1 s, Mon Repos 2.7 ± 0.1 s) and slower crawling speed in terms of both absolute speed and body lengths per second (La Roche Percée 2.5 ± 0.2 cm s–1 or 0.57 ± 0.05 body lengths s–1, Mon Repos 4.6 ± 0.1 cm s–1 or 1.04 ± 0.02 body lengths s–1). Nest temperatures at La Roche Percée approached the upper limit of embryo thermal tolerance towards the end of incubation (34°C) and this condition may contribute to the lower hatching and emergence success and lower fitness characteristics of hatchlings at the La Roche Percée rookery.
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