Studies on the embryology, ecology and evolution of sea turtles in the Eastern Mediterranean

1-) The temperature of sea turtle nests in the Eastern Mediterranean was between 24 and 35 "C and rose by up to 10 "C during incubation. 2-) The mean incubation temperature can be used for estimating the incubation period but provides a poor prediction of sex ratio. 3-) The mean temperature during the middle third of the incubation period was closely correlated with the percent sex ratio. 4-) There was a female dominated sex ratio among the 22 nests and only one loggerhead turtle nest showed less than a 50 % female sex ratio. 5-) There was a consistent temperature difference within the nest with top eggs warmer, bottom eggs cooler and middle ones intermediate. Therefore the majority of hatchlings 11'0111 [he top level in nests were females and those from the bottom level were predominantly males. 6-) Temperature differences within the nest also influenced the rate of development; the greater the difference in temperature between top and bottom the longer the time required to complete hatching of all embryos of the nest. The hatching intervals of green turtle nests were shorter than those at loggerhead turtle nests. Temperature variation between top and bottom of nests was low within green turtle nests. In general, a 1 "C temperature difference within the clutch caused a 4 day range in both hatching and emergence of hatchlings. 7-) Since the temperature within the nest and between the nests was so variable, sand air or sea water temperatures gave a poor prediction of the temperature of a nest and therefore the sex ratio. 8-) Although the predation pattern of sea turtle nests varied in relation to nest age, this predation can be reduced by screening the nest with mesh grids.9-) lnundation was one of the main abiotic factors lowering the hatching success on the beaches. Hatching success can be increased by relocating the nests to a safer area on the night of laying 10-) The mean grain sizes of sand ranged from 0.49 to 2.20 phi(<!»on 10 beaches but hatching success was not related to mean grain size of sand on the beaches. 11-) Simple embryonic staging of Mediterranean sea turtles was developed after measuring Cl set of selected morphological characteristics. The frequency of gross abnormalities among the samples was also calculated. Most common abnormalities were supernumerary and subnumerary scutes, albinos, head and jaw abnormalities and twinning l2-) The heavy metal concentrations III the tissues (yolk, liver and eggshell) of loggerhead turtle eggs and hatchlings were analysed. The concentrations of mercury, cadmium, lead, iron and copper were highest in the liver, while zinc concentrations were highest in the yolk. The concentrations of metals were similar on different beaches, except for lead concentrations in the eggshells, which varied between sites. 13 -) The genetic structure of loggerhead turtle samples from Cyprus exhibited haplotype B and green turtle samples haplotype XIII. No additional haplotypes were found. The presence of only single haplotypes suggests little variation in genetics within the Mediterranean and that these population were recently established by a small number of immigrants from the Atlantic

Sex ratio estimations of Chelonia mydas hatchlings at Samandağ Beach, Turkey

Samandağ Beach, an important nesting location for endangered green turtles (Chelonia mydas), is located at the most eastern part of the Mediterranean in Turkey. Hatchling sex ratio can be one of the key factors for green turtle protection, which is under the threat of global climate change. In this study, sex ratios of hatchlings were estimated by histological examination of dead hatchlings (n = 190) and by nest temperatures (n = 14) at Samandağ Beach between the 2003 and 2007 nesting seasons. The histological examination of dead C. mydas hatchlings and temperature-recorded nests indicated a female-biased sex ratio on Samandağ Beach. By histological examination, top and bottom levels of nests were recorded as 94% and 64% of females. Sex ratios during the middle third of the incubation period ranged from 39% to 97% for females with a mean of 74%. Distance from the sea was correlated with the middle third of incubation temperature (r = –0.604, P = 0.022) and female ratio (r = –0.573, P = 0.032). While nest temperatures and nest parameters such as hatching success, clutch size, nest distance from the sea and from vegetation, nest depth, and the day of emergence were not found significantly different among years (P > 0.05), incubation duration was found significantly different among years (P < 0.05). The results showed a female-dominated sex ratio by both histology and nest temperature. The knowledge of hatchling sex ratios provides information on demographic parameters, and coupled with appropriate conservation measures this can make important contributions to studies of climate change effects on green sea turtle populations. © TÜBİTAK

Age structures and growth parameters of the Levantine frog, Pelophylax bedriagae, at different localities in Denizli, Turkey

Skeletochronology is a reliable tool for assessing several parameters in amphibian populations. We used skeletochronology to determine the age structure, growth rate, age at first reproduction, and longevity of Levantine frog Pelophylax bedriagae populations from different localities in Denizli, Turkey. All examined individuals (N = 161) exhibited Lines of Arrested Growth in the bone cross-sections. Age structure and age at first reproduction were similar among localities and sexes, while longevity and growth rates showed significant variation among localities. Obtained results were compared with literature data on age-related and grow parameters in Pelophylax bedriagae and cognate species

Shallow genetic divergence indicates a Congo–Nile riverine connection for the softshell turtle Trionyx triunguis

WOS: 000288389500022We sequenced 20 new, field-collected individuals for up to seven genes to explore the phylogeography and conservation genetics of the threatened Nile softshell turtle Trionyx triunguis, including the first known-locality specimen from sub-Saharan Africa. Samples from Cameroon (West Africa), the Mediterranean and Nile River differed by at most a single nucleotide per gene, indicating the potential for a recent connection between these currently disjunct populations via the Nile-Congo River systems. Recently reported mitochondrial diversity between Mediterranean and "sub-Saharan" samples of the Nile softshell indicate that significant divergence exists across the species' range, but that variation cannot be fully incorporated into our analysis since those samples lack specific locality data.Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK); NSFNational Science Foundation (NSF) [DEB 0817042]; UC Davis Agricultural Experiment StationDwight Lawson collected the Cameroon turtle, and the San Diego Zoo provided a blood sample for our work, Permits were granted from the Republic of Turkey Ministry of Environment and Forestry. This work was supported by a grant from The Scientific and Technological Research Council of Turkey (TUBITAK), NSF grant DEB 0817042 and the UC Davis Agricultural Experiment Station. We thank Bob Thomson and members of the Shaffer lab for discussion. This study is a part of Muge Gidis's Ph.D. thesis

Mediterranean sea turtles: current knowledge and priorities for conservation and research

The available information regarding the 2 sea turtle species breeding in the Mediterranean (loggerhead turtle Caretta caretta and green turtle Chelonia mydas) is reviewed, including biometrics and morphology, identification of breeding and foraging areas, ecology and behaviour, abundance and trends, population structure and dynamics, anthropogenic threats and conservation measures. Although a large body of knowledge has been generated, research efforts have been inconsistently allocated across geographic areas, species and topics. Significant gaps still exist, ranging from the most fundamental aspects, such as the distribution of major nesting sites and the total number of clutches laid annually in the region, to more specific topics like age at maturity, survival rates and behavioural ecology, especially for certain areas (e.g. south-eastern Mediterranean). These gaps are particularly marked for the green turtle. The recent positive trends of nest counts at some nesting sites may be the result of the cessation of past exploitation and decades of conservation measures on land, both in the form of national regulations and of continued active protection of clutches. Therefore, the current status should be considered as dependent on such ongoing conservation efforts. Mitigation of incidental catch in fisheries, the main anthropogenic threat at sea, is still in its infancy. From the analysis of the present status a comprehensive list of research and conservation priorities is proposed

Are we working towards global research priorities for management and conservation of sea turtles?

In 2010, an international group of 35 sea turtle researchers refined an initial list of more than 200 research questions into 20 metaquestions that were considered key for management and conservation of sea turtles. These were classified under 5 categories: reproductive biology, biogeography, population ecology, threats and conservation strategies. To obtain a picture of how research is being focused towards these key questions, we undertook a systematic review of the peer-reviewed literature (2014 and 2015) attributing papers to the original 20 questions. In total, we reviewed 605 articles in full and from these 355 (59%) were judged to substantively address the 20 key questions, with others focusing on basic science and monitoring. Progress to answering the 20 questions was not uniform, and there were biases regarding focal turtle species, geographic scope and publication outlet. Whilst it offers some meaningful indications as to effort, quantifying peer-reviewed literature output is ob viously not the only, and possibly not the best, metric for understanding progress towards informing key conservation and management goals. Along with the literature review, an international group based on the original project consortium was assigned to critically summarise recent progress towards answering each of the 20 questions. We found that significant research is being expended towards global priorities for management and conservation of sea turtles. Although highly variable, there has been significant progress in all the key questions identified in 2010. Undertaking this critical review has highlighted that it may be timely to undertake one or more new prioritizing exercises. For this to have maximal benefit we make a range of recommendations for its execution. These include a far greater engagement with social sciences, widening the pool of contributors and focussing the questions, perhaps disaggregating ecology and conservatio

Network analysis of sea turtle movements and connectivity: A tool for conservation prioritization

Aim: Understanding the spatial ecology of animal movements is a critical element in conserving long-lived, highly mobile marine species. Analyzing networks developed from movements of six sea turtle species reveals marine connectivity and can help prioritize conservation efforts. Location: Global. Methods: We collated telemetry data from 1235 individuals and reviewed the literature to determine our dataset's representativeness. We used the telemetry data to develop spatial networks at different scales to examine areas, connections, and their geographic arrangement. We used graph theory metrics to compare networks across regions and species and to identify the role of important areas and connections. Results: Relevant literature and citations for data used in this study had very little overlap. Network analysis showed that sampling effort influenced network structure, and the arrangement of areas and connections for most networks was complex. However, important areas and connections identified by graph theory metrics can be different than areas of high data density. For the global network, marine regions in the Mediterranean had high closeness, while links with high betweenness among marine regions in the South Atlantic were critical for maintaining connectivity. Comparisons among species-specific networks showed that functional connectivity was related to movement ecology, resulting in networks composed of different areas and links. Main conclusions: Network analysis identified the structure and functional connectivity of the sea turtles in our sample at multiple scales. These network characteristics could help guide the coordination of management strategies for wide-ranging animals throughout their geographic extent. Most networks had complex structures that can contribute to greater robustness but may be more difficult to manage changes when compared to simpler forms. Area-based conservation measures would benefit sea turtle populations when directed toward areas with high closeness dominating network function. Promoting seascape connectivity of links with high betweenness would decrease network vulnerability.Fil: Kot, Connie Y.. University of Duke; Estados UnidosFil: Åkesson, Susanne. Lund University; SueciaFil: Alfaro Shigueto, Joanna. Universidad Cientifica del Sur; Perú. University of Exeter; Reino Unido. Pro Delphinus; PerúFil: Amorocho Llanos, Diego Fernando. Research Center for Environmental Management and Development; ColombiaFil: Antonopoulou, Marina. Emirates Wildlife Society-world Wide Fund For Nature; Emiratos Arabes UnidosFil: Balazs, George H.. Noaa Fisheries Service; Estados UnidosFil: Baverstock, Warren R.. The Aquarium and Dubai Turtle Rehabilitation Project; Emiratos Arabes UnidosFil: Blumenthal, Janice M.. Cayman Islands Government; Islas CaimánFil: Broderick, Annette C.. University of Exeter; Reino UnidoFil: Bruno, Ignacio. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Canbolat, Ali Fuat. Hacettepe Üniversitesi; Turquía. Ecological Research Society; TurquíaFil: Casale, Paolo. Università degli Studi di Pisa; ItaliaFil: Cejudo, Daniel. Universidad de Las Palmas de Gran Canaria; EspañaFil: Coyne, Michael S.. Seaturtle.org; Estados UnidosFil: Curtice, Corrie. University of Duke; Estados UnidosFil: DeLand, Sarah. University of Duke; Estados UnidosFil: DiMatteo, Andrew. CheloniData; Estados UnidosFil: Dodge, Kara. New England Aquarium; Estados UnidosFil: Dunn, Daniel C.. University of Queensland; Australia. The University of Queensland; Australia. University of Duke; Estados UnidosFil: Esteban, Nicole. Swansea University; Reino UnidoFil: Formia, Angela. Wildlife Conservation Society; Estados UnidosFil: Fuentes, Mariana M. P. B.. Florida State University; Estados UnidosFil: Fujioka, Ei. University of Duke; Estados UnidosFil: Garnier, Julie. The Zoological Society of London; Reino UnidoFil: Godfrey, Matthew H.. North Carolina Wildlife Resources Commission; Estados UnidosFil: Godley, Brendan J.. University of Exeter; Reino UnidoFil: González Carman, Victoria. Instituto National de Investigación y Desarrollo Pesquero; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Harrison, Autumn Lynn. Smithsonian Institution; Estados UnidosFil: Hart, Catherine E.. Grupo Tortuguero de las Californias A.C; México. Investigacion, Capacitacion y Soluciones Ambientales y Sociales A.C; MéxicoFil: Hawkes, Lucy A.. University of Exeter; Reino UnidoFil: Hays, Graeme C.. Deakin University; AustraliaFil: Hill, Nicholas. The Zoological Society of London; Reino UnidoFil: Hochscheid, Sandra. Stazione Zoologica Anton Dohrn; ItaliaFil: Kaska, Yakup. Dekamer—Sea Turtle Rescue Center; Turquía. Pamukkale Üniversitesi; TurquíaFil: Levy, Yaniv. University Of Haifa; Israel. Israel Nature And Parks Authority; IsraelFil: Ley Quiñónez, César P.. Instituto Politécnico Nacional; MéxicoFil: Lockhart, Gwen G.. Virginia Aquarium Marine Science Foundation; Estados Unidos. Naval Facilities Engineering Command; Estados UnidosFil: López-Mendilaharsu, Milagros. Projeto TAMAR; BrasilFil: Luschi, Paolo. Università degli Studi di Pisa; ItaliaFil: Mangel, Jeffrey C.. University of Exeter; Reino Unido. Pro Delphinus; PerúFil: Margaritoulis, Dimitris. Archelon; GreciaFil: Maxwell, Sara M.. University of Washington; Estados UnidosFil: McClellan, Catherine M.. University of Duke; Estados UnidosFil: Metcalfe, Kristian. University of Exeter; Reino UnidoFil: Mingozzi, Antonio. Università Della Calabria; ItaliaFil: Moncada, Felix G.. Centro de Investigaciones Pesqueras; CubaFil: Nichols, Wallace J.. California Academy Of Sciences; Estados Unidos. Center For The Blue Economy And International Environmental Policy Program; Estados UnidosFil: Parker, Denise M.. Noaa Fisheries Service; Estados UnidosFil: Patel, Samir H.. Coonamessett Farm Foundation; Estados Unidos. Drexel University; Estados UnidosFil: Pilcher, Nicolas J.. Marine Research Foundation; MalasiaFil: Poulin, Sarah. University of Duke; Estados UnidosFil: Read, Andrew J.. Duke University Marine Laboratory; Estados UnidosFil: Rees, ALan F.. University of Exeter; Reino Unido. Archelon; GreciaFil: Robinson, David P.. The Aquarium and Dubai Turtle Rehabilitation Project; Emiratos Arabes UnidosFil: Robinson, Nathan J.. Fundación Oceanogràfic; EspañaFil: Sandoval-Lugo, Alejandra G.. Instituto Politécnico Nacional; MéxicoFil: Schofield, Gail. Queen Mary University of London; Reino UnidoFil: Seminoff, Jeffrey A.. Noaa National Marine Fisheries Service Southwest Regional Office; Estados UnidosFil: Seney, Erin E.. University Of Central Florida; Estados UnidosFil: Snape, Robin T. E.. University of Exeter; Reino UnidoFil: Sözbilen, Dogan. Dekamer—sea Turtle Rescue Center; Turquía. Pamukkale University; TurquíaFil: Tomás, Jesús. Institut Cavanilles de Biodiversitat I Biologia Evolutiva; EspañaFil: Varo Cruz, Nuria. Universidad de Las Palmas de Gran Canaria; España. Ads Biodiversidad; España. Instituto Canario de Ciencias Marinas; EspañaFil: Wallace, Bryan P.. University of Duke; Estados Unidos. Ecolibrium, Inc.; Estados UnidosFil: Wildermann, Natalie E.. Texas A&M University; Estados UnidosFil: Witt, Matthew J.. University of Exeter; Reino UnidoFil: Zavala Norzagaray, Alan A.. Instituto politecnico nacional; MéxicoFil: Halpin, Patrick N.. University of Duke; Estados Unido

Genetic structure of Mediterranean sea turtle populations

The mitochondrial DNA (mtDNA) control region sequences of two species (Caretta caretta and Chelonia mydas) of sea turtles from the Mediterranean were analysed using samples from Northern Cyprus. Only one single haplotype for each species was detected. These results were compared with other published work regarding the genetic structure of sea turtle populations. These results suggest that the Mediterranean population of sea turtles were separated from their Atlantic relatives in the recent past. In order to protect these endangered sea turtles and to preserve the genetic diversity of the sea turtle population in the Mediterranean, individual nesting sites must be protected. That genetic studies can be done on the systematics of vertebrates, especially taxonomic studies of Herpetofauna, has also been shown by other related literature

Investigation of Caretta caretta population in Patara and Kızılot

In this survey, the numbers of nests, eggs and hatchlings of Caretta caretta population in Kızılot (1990) and Patara (1992) beaches and predators negative effect to their population were investigated during a single reproduction season. 299 emergences found out on Kızılot Beach during investigation season, four of them belong to Chelonia my das species and 295 of them belong to Caretta caretta. Among the emergences which belong to Caretta caretta, 143 (48,47 %) numbers of them had nested. From 4 emergences belong to Chelonia my das 3 of them had nested. Avarage eggs numbers at nests were 79,69 (min. 46, max. 137). Total eggs numbers among the 114 nests which were known to us were 9085. Only 7670 (84,42 %) hatchlings, emergenced from these eggs, have been able to reach to the sea. Majority of destroyed eggs and hatchlings have been destroyed utterly by foxes, harmful crabs and dogs. It was observed that some eggs' embryonic development could not be started or complated in some neste because of being in wet areas. Avarage of incubation periods for 70 nests was 59,63 (min. 51, max. 75) days. Straight carapace length of adult females which had measured was ftfr,44 (min. 59,0, max. 74,0) cm. The number of Caretta caretta emergence was 163 on Patara Bşach, among these 52 (31,90%) of them nested. Avarage eggs numbers at nests were 69,52 (min. 33, max. 134). Total eggs numbers in these nests were 2920. 1086 (37,19 %) hatchlings emergenced from these eggs have been able to reach to the sea. As at Kızılot Beach, eggs and hatchlings have been destroyed by foxes and harmful crabs in Patara Beach. Besides, since an important part of nests' residence was in wet areas, it was observed that embryonic development on these eggs could not start or complate exactly. Avarage of incubation periods for 25 nests was 60 (min. 51, max. 78) days. Straight carapace length of adult females which had measured was 74,50 (min. 66,0, max. 84,6) cm.Bu çalışmada, Caretta caretta' nın Kızılot (1990) ve Patara (1992) kumsallanndaki populasyonianrun bir üreme sezonunda yuva yapma, yumurta ve yavru sayıları ile bunlara zarar veren predator etkisi incelenmiştir. Araştırma sezonunda Kızılot Kumsalı'nda 299 adet çıkış saptanmış, bunlardan 4 tanesi Chelonia mydas türüne, 295 tanesi ise Caretta caretta ' ya aittir. Caretta caretta ' ya ait çıkışlardan 143 (%48,47) tanesinde yuva yapılmıştır. Chelonia mydas 'a ait 4 çıkıştan ise 3 tanesi yuva ile sonuçlanmıştır. Yuvalardaki ortalama yumurta sayısı 79,69 (min.46, max. 137) dur. Yumurta sayısı bilinen 114 yuvadaki toplam yumurta sayisı 9085'dir. Bu yumurtalardan çıkan ancak 7670 (% 84,42) yavru denize ulaşabilmiştir. Tahrip olan yumurta ve yavruların çoğunluğu tilkiler, kum yengeci ve köpekler tarafından tahrip edilmiş, yuvaların bir kısmı da nemli bölgede kaldığı için yumurtalarda embriyonik gelişim olmadığı veya tamamlanmadığı gözlenmiştir. Kuluçka süresi 70 yuva için ortalama 59,63 (min. 51, max. 75) gündür. Vücut ölçüsü alinan dişilerin Düz Karapax Boyu; 66,44 (min.59,0; max. 74,0) cm. dir. Patara Kumsalı'ndaki araştırmada ifâ 163 adet Caretta tarette çıkışı saptanmış ve bunlardan 52 (%3l,90)'si yuva İle sonuçlanmıştır. Toplam 42 yuvada ortalama yumurta sayısı 69,52 (min. 33, max. 134) dir. Bu yuvalardaki toplam yumurta sayısı 2920' dir. Bu yumurtalardan çıkan ancak 1086 (%37,19) yavru denize ulaşabilmiştir. Kızılot Kumsalı'nda olduğu gibi tahrip olan yumurta ve yavruların çoğunluğu tilkiler ve kum yengeçleri tarafından tahrip edilmiş, ayrıca yuvaların büyük bir kısmı nemli bölgede kaldığından yumurtalarda embriyonik gelişim olmadığı gözlenmiştir. Kuluçka süresi 25 yuva için ortalama 60 (min. 51, max. 78) gündür. Vücut ölçüsü alınan dişilerin Düz Karapax Boyu; 74,50 (min. 66,0; max. 84,6) cm. dir. I