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Catron S, Roth S, Zumpano F, Bintz J, Fordyce JA, Lenhart S, Miller DL, Wyneken J. Modeling the impacts of temperature during nesting seasons on Loggerhead (Caretta caretta) Sea Turtle populations in South Florida. Ecol Modell 2023. [DOI: 10.1016/j.ecolmodel.2023.110363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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2
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Cardona L, San Martín J, Benito L, Tomás J, Abella E, Eymar J, Aguilera M, Esteban JA, Tarragó A, Marco A. Global warming facilitates the nesting of the loggerhead turtle on the Mediterranean coast of Spain. Anim Conserv 2022. [DOI: 10.1111/acv.12828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- L. Cardona
- IRBio and Department of Evolutionary Biology, Ecology and Environmental Science, Faculty of Biology University of Barcelona Barcelona Spain
| | | | - L. Benito
- IRBio and Department of Evolutionary Biology, Ecology and Environmental Science, Faculty of Biology University of Barcelona Barcelona Spain
| | - J. Tomás
- Cavanilles Institute of Biodiversity and Evolutionary Biology University of Valencia Valencia Spain
| | - E. Abella
- BETA Technological Center, Universitat de Vic‐ Universitat Central de Catalunya Futurlab‐Can Baumann Vic Spain
| | - J. Eymar
- Conselleria de Agricultura, Desarrollo Rural, Emergencia Climática y Transición Ecológica Dirección General del Medio Natural, Servicio de Vida Silvestre Valencia Spain
| | - M. Aguilera
- BETA Technological Center, Universitat de Vic‐ Universitat Central de Catalunya Futurlab‐Can Baumann Vic Spain
| | | | - A. Tarragó
- Departament d'Acció Climàtica, Alimentació Agenda Rural Generalitat de Catalunya Barcelona Spain
| | - A. Marco
- Estación Biológica de Doñana CSIC Sevilla Spain
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3
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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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Booth DT, Turner AG, Laloë J, Limpus CJ. How well do embryo development rate models derived from laboratory data predict embryo development in sea turtle nests? JOURNAL OF EXPERIMENTAL ZOOLOGY PART A: ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2022; 337:516-526. [PMID: 35189044 PMCID: PMC9305169 DOI: 10.1002/jez.2585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 01/29/2022] [Accepted: 02/08/2022] [Indexed: 11/10/2022]
Abstract
Development rate of ectothermic animals varies with temperature. Here we use data derived from laboratory constant temperature incubation experiments to formulate development rate models that can be used to model embryonic development rate in sea turtle nests. We then use a novel method for detecting the time of hatching to measure the in situ incubation period of sea turtle clutches to test the accuracy of our models in predicting the incubation period from nest temperature traces. We found that all our models overestimated the incubation period. We hypothesize three possible explanations which are not mutually exclusive for the mismatch between our modeling and empirically measured in situ incubation period: (1) a difference in the way the incubation period is calculated in laboratory data and in our field nests, (2) inaccuracies in the assumptions made by our models at high incubation temperatures where there is no empirical laboratory data, and (3) a tendency for development rate in laboratory experiments to be progressively slower as temperature decreases compared with in situ incubation. We determined the hatching time in sea turtle nests and compared those with hatching times predicted from nest temperature traces. We found that nest temperature traces overestimated hatching time.
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Affiliation(s)
- David T. Booth
- School of Biological Sciences The University of Queensland St Lucia Queensland Australia
| | - Alysabeth G. Turner
- Animal and Veterinary Bioscience The University of Queensland St Lucia Queensland Australia
| | - Jacques‑Olivier Laloë
- School of Life and Environmental Sciences Deakin University Geelong Victoria Australia
| | - Colin J. Limpus
- Aquatic Threatened Species Unit Queensland Government Department of Science and Environment Brisbane Queensland Australia
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5
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Laloë JO, Chivers WJ, Esteban N, Hays GC. Reconstructing past thermal conditions in beach microclimates. GLOBAL CHANGE BIOLOGY 2021; 27:6592-6601. [PMID: 34558767 DOI: 10.1111/gcb.15903] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 06/13/2023]
Abstract
Reconstruction of past conditions provides important information on how ecosystems have been impacted by climate change, but generally for microhabitats worldwide there are no long-term empirical measurements. In these cases, there has been protracted debate about how various large-scale environmental proxies can best be used to reconstruct local temperatures. Here we help resolve this debate by examining how well environmental proxies hindcast sand temperatures at nest depths for five sea turtle nesting sites across the world. We link instrumental air temperature and sea surface temperature records with empirical sand temperature observations in the Atlantic (Ascension Island and Cape Verde), the Indian Ocean (Chagos Archipelago), the Caribbean (St Eustatius) and the Pacific (French Polynesia). We found strong correlations between sea surface temperatures, air temperatures and sand temperatures at all our study sites. Furthermore, Granger causality testing shows variations in sea surface temperature and air temperature precede variations in sand temperatures. We found that different proxies (air or sea temperature or a combination of both) predicted mean monthly sand temperatures within <0.5°C of empirical observations. Reconstructions of sand temperatures over the last 170 years reveal a slight warming of temperatures (maximum 0.5°C per century). An analysis of 36 published datasets revealed that the gradient of the relationship between sand temperature and air temperature is relatively constant, suggesting long-term changes in sand temperature could be extended around the world to include nesting sites where there are no empirical measurements of sand temperature. Our approaches are likely to have utility for a range of microhabitats where there is an interest in long-term changes in temperature.
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Affiliation(s)
- Jacques-Olivier Laloë
- School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
| | - William J Chivers
- School of Electrical Engineering and Computing, University of Newcastle, Callaghan, New South Wales, Australia
| | - Nicole Esteban
- Faculty of Science and Engineering, Swansea University, Swansea, Wales, United Kingdom
| | - Graeme C Hays
- School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
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Corner RD, Cribb TH, Cutmore SC. Vermetid gastropods as key intermediate hosts for a lineage of marine turtle blood flukes (Digenea: Spirorchiidae), with evidence of transmission at a turtle rookery. Int J Parasitol 2021; 52:225-241. [PMID: 34742720 DOI: 10.1016/j.ijpara.2021.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 11/30/2022]
Abstract
Blood flukes of the family Spirorchiidae Stunkard, 1921 are significant pathogens of marine turtles, both in the wild and in captivity. Despite causing considerable disease and mortality, little is known about the life cycles of marine species, with just four reports globally. No complete life cycle has been elucidated for any named species of marine spirorchiid, but the group is reported to use vermetid and fissurellid gastropods, and terebelliform polychaetes as intermediate hosts. Here we report molecular evidence that nine related spirorchiid species infect vermetid gastropods as first intermediate hosts from four localities along the coast of Queensland, Australia. ITS2 rDNA and cox1 mtDNA sequence data generated from vermetid infections provides the first definitive identifications for the intermediate hosts for the four species of Hapalotrema Looss, 1899 and Learedius learedi Price, 1934. Additionally, we provide a new locality report for larval stages of Amphiorchis sp., and evidence of three additional unidentified spirorchiid species in Australian waters. Based on the wealth of infections from vermetids during this study, we conclude that the previous preliminary report of a fissurellid limpet as the intermediate host for L. learedi was likely mistaken. The nine species found infecting vermetids during this study form a strongly supported clade exclusive of species of the other two marine spirorchiid genera for which sequence data are available; Carettacola Manter & Larson, 1950 which falls sister to the vermetid-infecting clade + a small clade of freshwater spirorchiids, and Neospirorchis Price, 1934 which is distantly related to the vermetid-infecting clade. We provide further evidence that spirorchiid transmission can occur in closed system aquaria and show that spirorchiid transmission occurs at both an important turtle rookery (Heron Island, southern Great Barrier Reef, Australia) and foraging ground (Moreton Bay, Australia). We discuss the implications of our findings for the epidemiology of the disease, control in captivity, and the evolution of vermetid exploitation by the Spirorchiidae.
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Affiliation(s)
- Richard D Corner
- The University of Queensland, School of Biological Sciences, St Lucia, Queensland 4072, Australia.
| | - Thomas H Cribb
- The University of Queensland, School of Biological Sciences, St Lucia, Queensland 4072, Australia
| | - Scott C Cutmore
- The University of Queensland, School of Biological Sciences, St Lucia, Queensland 4072, Australia
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7
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Porter E, Booth DT, Limpus CJ, Staines MN, Smith CE. Influence of short-term temperature drops on sex-determination in sea turtles. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2021; 335:649-658. [PMID: 34313387 DOI: 10.1002/jez.2509] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 06/30/2021] [Accepted: 07/09/2021] [Indexed: 11/08/2022]
Abstract
All sea turtles exhibit temperature-dependent sex-determination, where warmer temperatures produce mostly females and cooler temperatures produce mostly males. As global temperatures continue to rise, sea turtle sex-ratios are expected to become increasingly female-biased, threatening the long-term viability of many populations. Nest temperatures are dependent on sand temperature, and heavy rainfall events reduce sand temperatures for a brief period. However, it is unknown whether these short-term temperature drops are large and long enough to produce male hatchlings. To discover if short-term temperature drops within the sex-determining period can lead to male hatchling production, we exposed green and loggerhead turtle eggs to short-term temperature drops conducted in constant temperature rooms. We dropped incubation temperature at four different times during the sex-determining period for a duration of either 3 or 7 days to mimic short-term drops in temperature caused by heavy rainfall in nature. Some male hatchlings were produced when exposed to temperature drops for as little as 3 days, but the majority of male production occurred when eggs were exposed to 7 days of lowered temperature. More male hatchlings were produced when the temperature drop occurred during the middle of the sex-determining period in green turtles, and the beginning and end of the sex-determining period in loggerhead turtles. Inter-clutch variation was evident in the proportion of male hatchlings produced, indicating that maternal and or genetic factors influence male hatchling production. Our findings have management implications for the long-term preservation of sea turtles on beaches that exhibit strongly female-biased hatchling sex-ratios.
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Affiliation(s)
- Ellen Porter
- School of Biological Sciences, Faculty of Science, The University of Queensland, Brisbane, Queensland, Australia
| | - David T Booth
- School of Biological Sciences, Faculty of Science, The University of Queensland, Brisbane, Queensland, Australia
| | - Colin J Limpus
- Queensland Government Department of Science and Environment, Aquatic Threatened Species Unit, Brisbane, Queensland, Australia
| | - Melissa N Staines
- School of Biological Sciences, Faculty of Science, The University of Queensland, Brisbane, Queensland, Australia
| | - Caitlin E Smith
- Brisbane Office, World Wildlife Fund Australia, Brisbane, Australia
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8
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Pusapati C, Manoharakrishnan M, Phillott AD, Shanker K. Effect of Hatchery Nest Environment on Olive Ridley (Lepidochelys olivacea) Hatchling Performance. CHELONIAN CONSERVATION AND BIOLOGY 2021. [DOI: 10.2744/ccb-1450.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Chandana Pusapati
- TERI School of Advanced Studies, Plot 10, Institutional Area, Vasant Kunj, New Delhi 110070, India []
| | | | - Andrea D. Phillott
- Dakshin Foundation, 1818, 9th Cross, 5th Main, Sahakar Nagar B block, Bangalore 560092, Karnataka, India []
| | - Kartik Shanker
- Dakshin Foundation, 1818, 9th Cross, 5th Main, Sahakar Nagar B block, Bangalore 560092, Karnataka, India []
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9
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Bentley BP, Stubbs JL, Whiting SD, Mitchell NJ. Variation in thermal traits describing sex determination and development in Western Australian sea turtle populations. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13645] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Blair P. Bentley
- School of Biological Sciences The University of Western Australia Crawley WA Australia
| | - Jessica L. Stubbs
- School of Biological Sciences The University of Western Australia Crawley WA Australia
| | - Scott D. Whiting
- Marine Science Program Department of Biodiversity, Conservation and Attractions Kensington WA Australia
| | - Nicola J. Mitchell
- School of Biological Sciences The University of Western Australia Crawley WA Australia
- Oceans Institute The University of Western Australia Crawley WA Australia
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10
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Massey MD, Congdon JD, Davy C, Rollinson N. First Evidence of Metabolic Heating in a Freshwater Turtle (Chelydra serpentina). CHELONIAN CONSERVATION AND BIOLOGY 2019. [DOI: 10.2744/ccb-1356.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Melanie D. Massey
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario M5S 3B2 Canada []
| | - Justin D. Congdon
- Savannah River Ecology Laboratory, Drawer E, Aiken, South Carolina 29802 USA []
| | - Christina Davy
- Wildlife Research and Monitoring Section, Ontario Ministry of Natural Resources & Forestry. 2140 East Bank Drive, Peterborough, Ontario K9J 7B8 Canada
| | - Njal Rollinson
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario M5S 3B2 Canada []
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11
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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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12
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Massey MD, Holt SM, Brooks RJ, Rollinson N. Measurement and modelling of primary sex ratios for species with temperature-dependent sex determination. ACTA ACUST UNITED AC 2019; 222:jeb.190215. [PMID: 30352829 DOI: 10.1242/jeb.190215] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 10/16/2018] [Indexed: 02/04/2023]
Abstract
For many oviparous animals, incubation temperature influences sex through temperature-dependent sex determination (TSD). Although climate change may skew sex ratios in species with TSD, few available methods predict sex under natural conditions, fewer still are based on mechanistic hypotheses of development, and field tests of existing methods are rare. We propose a new approach that calculates the probability of masculinization (PM) in natural nests. This approach subsumes the mechanistic hypotheses describing the outcome of TSD, by integrating embryonic development with the temperature-dependent reaction norm for sex determination. Further, we modify a commonly used method of sex ratio estimation, the constant temperature equivalent (CTE), to provide quantitative estimates of sex ratios. We test our new approaches using snapping turtles (Chelydra serpentina). We experimentally manipulated nests in the field, and found that the PM method is better supported than the modified CTE, explaining 69% of the variation in sex ratios across 27 semi-natural nests. Next, we used the PM method to predict variation in sex ratios across 14 natural nests over 2 years, explaining 67% of the variation. We suggest that the PM approach is effective and broadly applicable to species with TSD, particularly for forecasting how sex ratios may respond to climate change. Interestingly, we also found that the modified CTE explained up to 64% of variation in sex ratios in a Type II TSD species, suggesting that our modifications will be useful for future research. Finally, our data suggest that the Algonquin Park population of snapping turtles possesses resilience to biased sex ratios under climate change.
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Affiliation(s)
- Melanie D Massey
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON M5S 3B2, Canada
| | - Sarah M Holt
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Ronald J Brooks
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Njal Rollinson
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON M5S 3B2, Canada.,School of the Environment, University of Toronto, 33 Willcocks Street, Toronto, ON M5S 3E8, Canada
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Girondot M, Monsinjon J, Guillon JM. Delimitation of the embryonic thermosensitive period for sex determination using an embryo growth model reveals a potential bias for sex ratio prediction in turtles. J Therm Biol 2018; 73:32-40. [PMID: 29549989 DOI: 10.1016/j.jtherbio.2018.02.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 02/08/2018] [Accepted: 02/08/2018] [Indexed: 10/18/2022]
Abstract
The sexual phenotype of the gonad is dependent on incubation temperature in many turtles, all crocodilians, and some lepidosaurians. At hatching, identification of sexual phenotype is impossible without sacrificing the neonates. For this reason, a general method to infer sexual phenotype from incubation temperatures is needed. Temperature influences sex determination during a specific period of the embryonic development, starting when the gonad begins to form. At constant incubation temperatures, this thermosensitive period for sex determination (TSP) is located at the middle third of incubation duration (MTID). When temperature fluctuates, the position of the thermosensitive period for sex determination can be shifted from the MTID because embryo growth is affected by temperature. A method is proposed to locate the thermosensitive period for sex determination based on modelling the embryo growth, allowing its precise identification from a natural regime of temperatures. Results from natural nests and simulations show that the approximation of the thermosensitive period for sex determination to the middle third of incubation duration may create a quasi-systematic bias to lower temperatures when computing the average incubation temperature during this period and thus a male-bias for sex ratio estimate.
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Affiliation(s)
- Marc Girondot
- Ecologie, Systématique, Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91400 Orsay, France.
| | - Jonathan Monsinjon
- Ecologie, Systématique, Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91400 Orsay, France.
| | - Jean-Michel Guillon
- Ecologie, Systématique, Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91400 Orsay, France.
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Stewart TA, Booth DT, Rusli MU. Influence of sand grain size and nest microenvironment on incubation success, hatchling morphology and locomotion performance of green turtles (Chelonia mydas) at the Chagar Hutang Turtle Sanctuary, Redang Island, Malaysia. AUST J ZOOL 2018. [DOI: 10.1071/zo19025] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The nest microenvironment affects hatching and emergence success, sex ratios, morphology, and locomotion performance of hatchling sea turtles. Sand grain size is hypothesised to influence the nest microenvironment, but the influence of sand grain size on incubation of sea turtle eggs has rarely been experimentally tested. At the Chagar Hutang Turtle Sanctuary, Redang Island, Malaysia, green turtle (Chelonia mydas) nests were relocated to sands with different sand grain sizes on a natural beach to assess whether grain size affects nest temperature, oxygen partial pressure inside the nest, incubation success, hatchling morphology and hatchling locomotion performance. Green turtle nests in coarse sand were cooler; however, hatching success, nest emergence success, oxygen partial pressure, incubation length and hatchling size were not influenced by sand particle size. Nests in medium-grained sands were warmest, and hatchlings from these nests were better self-righters but poorer crawlers and swimmers. Hatchling self-righting ability was not correlated with crawling speed or swimming speed, but crawling speed was correlated with swimming speed, with hatchlings typically swimming 1.5–2 times faster than they crawled. Hence, we found that sand particle size had minimal influence on the nest microenvironment and hatchling outcomes.
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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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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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Kobayashi S, Saito Y, Osawa A, Katsumata E, Karaki I, Nagaoka K, Taya K, Watanabe G. Embryonic sex steroid hormones accumulate in the eggshell of loggerhead sea turtle (Caretta caretta). Gen Comp Endocrinol 2015; 224:11-7. [PMID: 26050561 DOI: 10.1016/j.ygcen.2015.05.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 05/26/2015] [Accepted: 05/28/2015] [Indexed: 11/24/2022]
Abstract
Steroids hormones such as estradiol-17β (E2) and testosterone (T) are involved in gonadal differentiation of oviparous animals with temperature-dependent sex determination (TSD), and are greatly distributed. This hypothesizes that these embryonic steroid hormones probably accumulate in the eggshell throughout blood or/and chorioallantoic fluid in sea turtle species with TSD, producing females at higher temperature. To demonstrate this hypothesis, concentrations of E2 and T in the blood plasma from the hatchling loggerhead sea turtle (Caretta caretta) and in their eggshells were measured by radioimmunoassay. In the present study we propose that both concentrations of E2 and T in the blood plasma are correlated with amounts of these sex steroids in the eggshell. Moreover, contents of E2 in the eggshell showed a significant positive correlation with mean incubation temperatures during a thermosensitive period in the experimental nests, whereas T contents in the eggshell did not. Taken together, these findings indicated that embryonic E2 and T that accumulated in the eggshell can be extracted and measured. Furthermore, the present study suggested that contents of E2 in the eggshell may differ between male and female, and monitoring of these steroids is a useful method to identify the sex of loggerhead sea turtle hatchling.
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Affiliation(s)
- Shohei Kobayashi
- Department of Biological Production Science, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan
| | | | | | | | | | - Kentaro Nagaoka
- Laboratory of Veterinary Physiology, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-0054, Japan
| | - Kazuyoshi Taya
- Kamogawa Sea World, Chiba 296-0041, Japan; Laboratory of Veterinary Physiology, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-0054, Japan
| | - Gen Watanabe
- Laboratory of Veterinary Physiology, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-0054, Japan.
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19
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Refsnider JM, Janzen FJ. Temperature-Dependent Sex Determination under Rapid Anthropogenic Environmental Change: Evolution at a Turtle’s Pace? J Hered 2015; 107:61-70. [DOI: 10.1093/jhered/esv053] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Accepted: 07/02/2015] [Indexed: 11/14/2022] 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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Wyneken J, Lolavar A. Loggerhead sea turtle environmental sex determination: Implications of moisture and temperature for climate change based predictions for species survival. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2015; 324:295-314. [DOI: 10.1002/jez.b.22620] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 03/02/2015] [Indexed: 11/09/2022]
Affiliation(s)
- Jeanette Wyneken
- Department of Biological Sciences; Florida Atlantic University; Boca Raton Florida
| | - Alexandra Lolavar
- Department of Biological Sciences; Florida Atlantic University; Boca Raton Florida
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Alfaro-Núñez A, Jensen MP, Abreu-Grobois FA. Does polyandry really pay off? The effects of multiple mating and number of fathers on morphological traits and survival in clutches of nesting green turtles at Tortuguero. PeerJ 2015; 3:e880. [PMID: 25870773 PMCID: PMC4393808 DOI: 10.7717/peerj.880] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 03/17/2015] [Indexed: 11/30/2022] Open
Abstract
Despite the long debate of whether or not multiple mating benefits the offspring, studies still show contradictory results. Multiple mating takes time and energy. Thus, if females fertilize their eggs with a single mating, why to mate more than once? We investigated and inferred paternal identity and number of sires in 12 clutches (240 hatchlings) of green turtles (Chelonia mydas) nests at Tortuguero, Costa Rica. Paternal alleles were inferred through comparison of maternal and hatchling genotypes, and indicated multiple paternity in at least 11 of the clutches (92%). The inferred average number of fathers was three (ranging from 1 to 5). Moreover, regression analyses were used to investigate for correlation of inferred clutch paternity with morphological traits of hatchlings fitness (emergence success, length, weight and crawling speed), the size of the mother, and an environmental variable (incubation temperature). We suggest and propose two different comparative approaches for evaluating morphological traits and clutch paternity, in order to infer greater offspring survival. First, clutches coded by the exact number of fathers and second by the exact paternal contribution (fathers who gives greater proportion of the offspring per nest). We found significant differences (P < 0.05) in clutches coded by the exact number of fathers for all morphological traits. A general tendency of higher values in offspring sired by two to three fathers was observed for the length and weight traits. However, emergence success and crawling speed showed different trends which unable us to reach any further conclusion. The second approach analysing the paternal contribution showed no significant difference (P > 0.05) for any of the traits. We conclude that multiple paternity does not provide any extra benefit in the morphological fitness traits or the survival of the offspring, when analysed following the proposed comparative statistical methods.
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Affiliation(s)
- Alonzo Alfaro-Núñez
- Center for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen , Copenhagen , Denmark
| | - Michael P Jensen
- Marine Mammal and Turtle Division, National Oceanic and Atmospheric Administration , La Jolla, CA , United States
| | - F Alberto Abreu-Grobois
- Laboratorio de Genética, Unidad Académica Mazatlán, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México , México
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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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Population sex ratios under differing local climates in a reptile with environmental sex determination. Evol Ecol 2014. [DOI: 10.1007/s10682-014-9710-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Maulany RI, Booth DT, Baxter GS. Emergence Success and Sex Ratio of Natural and Relocated Nests of Olive Ridley Turtles from Alas Purwo National Park, East Java, Indonesia. COPEIA 2012. [DOI: 10.1643/ch-12-088] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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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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Sieg AE, Binckley CA, Wallace BP, Tomillo PS, Reina RD, Paladino FV, Spotila JR. Sex ratios of leatherback turtles: hatchery translocation decreases metabolic heating and female bias. ENDANGER SPECIES RES 2011. [DOI: 10.3354/esr00372] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Warm water and cool nests are best. How global warming might influence hatchling green turtle swimming performance. PLoS One 2011; 6:e23162. [PMID: 21826236 PMCID: PMC3149641 DOI: 10.1371/journal.pone.0023162] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 07/07/2011] [Indexed: 11/19/2022] Open
Abstract
For sea turtles nesting on beaches surrounded by coral reefs, the most important element of hatchling recruitment is escaping predation by fish as they swim across the fringing reef, and as a consequence hatchlings that minimize their exposure to fish predation by minimizing the time spent crossing the fringing reef have a greater chance of surviving the reef crossing. One way to decrease the time required to cross the fringing reef is to maximize swimming speed. We found that both water temperature and nest temperature influence swimming performance of hatchling green turtles, but in opposite directions. Warm water increases swimming ability, with hatchling turtles swimming in warm water having a faster stroke rate, while an increase in nest temperature decreases swimming ability with hatchlings from warm nests producing less thrust per stroke.
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DeGregorio BA, Williard AS. Incubation Temperatures and Metabolic Heating of Relocated and In Situ Loggerhead Sea Turtle (Caretta caretta) Nests at a Northern Rookery. CHELONIAN CONSERVATION AND BIOLOGY 2011. [DOI: 10.2744/ccb-0880.1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Poloczanska ES, Limpus CJ, Hays GC. Chapter 2. Vulnerability of marine turtles to climate change. ADVANCES IN MARINE BIOLOGY 2009; 56:151-211. [PMID: 19895975 DOI: 10.1016/s0065-2881(09)56002-6] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Marine turtles are generally viewed as vulnerable to climate change because of the role that temperature plays in the sex determination of embryos, their long life history, long age-to-maturity and their highly migratory nature. Extant species of marine turtles probably arose during the mid-late Jurassic period (180-150 Mya) so have survived past shifts in climate, including glacial periods and warm events and therefore have some capacity for adaptation. The present-day rates of increase of atmospheric greenhouse gas concentrations, and associated temperature changes, are very rapid; the capacity of marine turtles to adapt to this rapid change may be compromised by their relatively long generation times. We consider the evidence and likely consequences of present-day trends of climate change on marine turtles. Impacts are likely to be complex and may be positive as well as negative. For example, rising sea levels and increased storm intensity will negatively impact turtle nesting beaches; however, extreme storms can also lead to coastal accretion. Alteration of wind patterns and ocean currents will have implications for juveniles and adults in the open ocean. Warming temperatures are likely to impact directly all turtle life stages, such as the sex determination of embryos in the nest and growth rates. Warming of 2 degrees C could potentially result in a large shift in sex ratios towards females at many rookeries, although some populations may be resilient to warming if female biases remain within levels where population success is not impaired. Indirectly, climate change is likely to impact turtles through changes in food availability. The highly migratory nature of turtles and their ability to move considerable distances in short periods of time should increase their resilience to climate change. However, any such resilience of marine turtles to climate change is likely to be severely compromised by other anthropogenic influences. Development of coastlines may threaten nesting beaches and reproductive success, and pollution and eutrophication is threatening important coastal foraging habitats for turtles worldwide. Exploitation and bycatch in other fisheries has seriously reduced marine turtle populations. The synergistic effects of other human-induced stressors may seriously reduce the capacity of some turtle populations to adapt to the current rates of climate change. Conservation recommendations to increase the capacity of marine turtle populations to adapt to climate change include increasing population resilience, for example by the use of turtle exclusion devices in fisheries, protection of nesting beaches from the viewpoints of both conservation and coastal management, and increased international conservation efforts to protect turtles in regions where there is high unregulated or illegal fisheries (including turtle harvesting). Increasing research efforts on the critical knowledge gaps of processes influencing population numbers, such as identifying ocean foraging hotspots or the processes that underlie the initiation of nesting migrations and selection of breeding areas, will inform adaptive management in a changing climate.
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Affiliation(s)
- Elvira S Poloczanska
- Climate Adaptation Flagship, CSIRO Marine and Atmospheric Research, Cleveland, Queensland 4163, Australia
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