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In this study, we present the first in-water monitoring results of loggerhead turtles (Caretta caretta) in Koycegiz-Dalyan specially protected area (SPA), Turkey. The capture-mark-recapture (CMR) study encompassed a total of 113 capture events of 88 individuals across two sampling years. The majority of the population was adults (88.6%) with a highly male-biased (70.5%) sex ratio. Our results indicate that some of the overwintering individuals also contribute to the nesting population in the region. Biometric characteristics of captured individuals were also presented. Additionally, we found the population to be under heavy anthropogenic threats with 54.5% of the captured individuals exhibiting results of previous anthropogenically caused injuries. Our results suggest that Koycegiz-Dalyan SPA is an important overwintering and foraging area for loggerhead turtles, which is currently an indexed nesting site for loggerhead turtles in the Mediterranean. Given the possible feminization effects of climate change on future marine turtle populations, the male-biased population in the study area is of the greatest importance, and together with having an indexed nesting site, the area should therefore be regarded as an important marine turtle area.

To determine blood biochemistry and reassess and compare red blood cell morphology based on individuals' gender, age and SVL (Snout-Vent Length), we studied 30 blood samples of Bufotes variabilis (15 males, 15 females) from Omaz Valley, Denizli/Turkey. For age determination, bone samples were threated according to the skeletochronology procedure and a strong positive correlation between SVL and age structure (Pearson's, n = 30, r(2) = 0.937, p < 0.001) was detected. Like all anurans, the shapes of the erythrocytes and their nuclei were ellipsoidal while their dimensions were bigger than expected when compared with those in the previous studies. Statistical evaluations of the red blood cells were made according to individuals' gender, age and SVL and no significant differences were found amongst them. This is the first study about the blood biochemistry of B. variabilis which includes pH, blood gas, oximetry, electrolyte (potassium, sodium, calcium, chloride and bicarbonate ion concentrations) and metabolite ED-glucose and L(+)-lactate concentration] values. Biochemical data were statistically analysed according to gender, age and SVL to evaluate whether there are any relationships or differences between the studied individuals. Statistical analyses of the biochemical assessments showed that cCa values of females were significantly high (t-test: t = 2.30, df = 20, p < 0.05), possibly due to the spawning period. The mean value of the individuals' age was 7.77 +/- 1.33 years with the mean SVL of 80.4 +/- 1.2 mm. Pearson's correlations of the biochemical data indicated a very significant relationship between cCl ion concentration and SVL as well as age. However, highly significant positive correlations were found between SO2 - pO(2), FO(2)Hb - pO(2), FO(2)Hb - sO(2), FHHb - pCO(2), cNa - pH, cNa - cK, cCa - cK, cCa - cNa, cHO(3) - pCO(2) and cLac - cGlu values while pO(2) - pCO(2), SO2 - pCO(2), FHHb - pO(2), FHHb - sO(2), FHHb - FO(2)Hb, cK - pCO(2) values showed a very significant negative correlation. These are the first biochemical data and evaluations about B. variabilis blood. In addition, according to the data obtained in our study, it is possible to say that age can be used as a substitute of SVL when it is not possible to procure the exact measurements of an individual for assessment. C1 [Ulubeli, Sevay Ayse; Baskale, Eyup; Kaska, Yakup] Pamukkale Univ, Dept Biol, Denizli, Turkey.

Sea turtles suffer from numerous threats such as predation, tidal inundation, and coastal building. We aimed to assess the effectiveness of hatchery technique on Göksu Delta beach, Turkey during the nesting season of 2010. For this purpose, eggs of loggerhead turtle (Caretta caretta) nests under the risk of tidal inundation were transferred into two protected hatchery sites that were constructed on Göksu Delta beach, in which there were no risk of predation and inundation, and the other nests were left to remain in situ. Hatching success of hatchery and natural nests were calculated. In addition, temperatures of both hatchery and natural nests (5 and 6 nests, respectively) were recorded, and sex ratios were determined using these nest temperatures and incubation periods. It was determined that hatching success increased with increasing distance from the sea (until 31 m) (r2 = 0.98), increasing incubation period (up to 60 days) (r2 = 0.68), and decreasing clutch size (r2 = 0.93), implying that the production of male hatchling is high in a nest if hatching success of that nest is high (or vice versa). Mean hatching success, incubation period, and nest temperature for hatchery nests were found to be 72.8%, 51.1 days, and 30.2 °C, respectively, while the corresponding values for natural nests were found to be 40.5%, 49.9 days, and 31.1 °C, respectively. It was also detected that hatchery nests produced higher proportion of male hatchlings (25.2%) compared with natural nests (13.5%). Based on all these results, it can be concluded that hatchery management on this beach is not a completely effective conservation technique. Nest relocation and/or hatchery management enable the conservationists to increase hatching success rate, but they cause sex ratio alteration. In this respect, we can only partially support nest relocation and/or hatchery management. They should be considered as a last option due to sex ratio alteration. © 2017 Elsevier Ltd

Sea turtles are promiscuous breeders with both males and females mating multiply. Due to this mating system, multiple paternity (MP) occurs in sea turtle clutches, and the frequency of MP varies greatly within and among species. In this study, the paternity of a population of loggerhead sea turtles (Caretta caretta) nesting on Dalyan Beach in Turkey was investigated using two highly polymorphic microsatellite markers (CcP2F11 and CcP7C06). Tissue samples collected from randomly selected hatchlings (a total of 522 hatchlings) from two to three successive clutches (a total of 25 clutches) of 10 nesting females were used for paternity analysis with an average sampling effort of 28.2% of offspring per clutch. Evidence of MP in seven out of 10 females (70%) was found, and it was detected that four out of these seven females mated with at least two males, whereas the remaining three females with at least three males. By analysing the successive clutches of females, it was detected that both the number and genotype of contributing sires was same in all clutches of a given female, possibly due to the lack of successful inter-nesting mating in this population. The high frequency of MP implies the possible high genetic diversity within this population. This study indicates that the density of individuals may be the reason of the high frequency of MP in this relatively small population because mating takes place mainly in a narrow area in Dalyan. The possible mating behaviours of the sea turtles and their population structures were discussed in light of the high frequency of MP within this population reported for the first time. © 2016 Elsevier B.V.

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 re search and conservation priorities is proposed. © The authors 2018.

The assessment of the composition and dynamics of endangered populations is crucial for management and conservation, and appropriate genetic markers are critical. The genetic structuring of the Mediterranean green turtle (Chelonia mydas) populations and the origin of the stranded animals found along the Israeli coast was investigated using new highly polymorphic short tandem repeat (STR) markers. The structuring of nesting populations was studied using pairwise genetic distances and a principal coordinates analysis (PCoA). The contribution of the different nesting populations to the stranded sample was assessed by using a mixed-stock analysis. A clear population genetic structure, not detected before, has been revealed. The four nesting populations are genetically well differentiated, and thus should be considered as different management units. The populations from Turkey and Israel showed higher resemblance, despite residing at opposite ends of the Mediterranean distribution. The Turkish nesting population is the main source of the stranded turtles sampled along the Israeli shore, confirming that individuals from this population migrate from north to south along the eastern shore of the Mediterranean, as previously shown by telemetry studies. The use of a highly polymorphic haplotyping method enabled the detection of a clear genetic structuring of the green turtle populations in the eastern Mediterranean Sea that was not revealed in previous studies, demonstrating the importance of marker selection in population genetics. The analysis of the genetic composition of the stranded turtles allowed us to investigate the migration patterns from nesting to foraging areas, supporting previous satellite-tracking and stable-isotope results. These results will help to delineate conservation management units for the species in the Mediterranean, and reveal connectivity among beaches and mixed aggregations. Copyright © 2018 John Wiley & Sons, Ltd.

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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.