Population estimate and body size of European pond turtles (Emys orbicularis) from Pazarağaç (Afyonkarahisar/Turkey)

AbstractData on population size, adult sex ratio, body size and mass are provided for a population of the turtle Emys orbicularis near Pazarağaç (Afyonkarahisar/Turkey). Using the mark-recapture method (triple catch), a population size of 664 turtles was estimated (95% confidence interval, range 332–996), corresponding to a density of 83 turtles per hectare (range 41.5–124.5). The adult sex-ratio was significantly skewed in favor of males (2.02 males: 1 female; P < 0.001). Almost all recorded specimens were adult (98.1%). Mean straight carapace length (SCL) and body mass (BM) of adult turtles were: SCL = 128.65 mm, BM = 345 g for males (n = 168) and SCL = 135.37 mm, BM = 463 g for females (n = 83).

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Population structure of Emys orbicularis in the Bardello (Po Delta, Northern Italy)

Amphibia-Reptilia ◽

10.1163/156853895x00217 ◽

1995 ◽

Vol 16 (1) ◽

pp. 77-85 ◽

Cited By ~ 7

Author(s):

Stefano Mazzotti

Keyword(s):

Population Structure ◽

Sexual Dimorphism ◽

Sex Ratio ◽

Population Size ◽

Carapace Length ◽

Shell Height ◽

Northern Italy ◽

Emys Orbicularis ◽

Frequency Distributions ◽

Po Delta

AbstractA population of Emys orbicularis in the Bardello (Po Delta, Northern Italy) was studied for 3 years using capture-mark-recapture methods, 23.6% of which were male, 57,5% female and 18.9% were juvenile specimens. The sex ratio of 127 specimens was 1:2. Certain morphometric variables such as the carapace length and shell height were examined in order to establish their sexual dimorphism. The population structure was defined by means of frequency distributions of carapace length. Using the Lincoln-Petersen and Jolly-Seber indices it was possible to estimate the population size as an average of 7.2 specimens per hectare.

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Modelling seasonal and annual variation in size at functional maturity in the European lobster (Homarus gammarus) from self-sampling data

ICES Journal of Marine Science ◽

10.1093/icesjms/fsp166 ◽

2009 ◽

Vol 66 (9) ◽

pp. 1892-1898 ◽

Cited By ~ 8

Author(s):

Martial Laurans ◽

Spyros Fifas ◽

Sébastien Demaneche ◽

Stéphane Brérette ◽

Olivier Debec

Keyword(s):

Body Size ◽

Sex Ratio ◽

Carapace Length ◽

Annual Variation ◽

Logistic Function ◽

Sampled Data ◽

Functional Maturity ◽

European Lobster ◽

Homarus Gammarus ◽

Northern European

Abstract Laurans, M., Fifas, S., Demaneche, S., Brérette, S., and Debec, O. 2009. Modelling seasonal and annual variation in size at functional maturity in the European lobster (Homarus gammarus) from self-sampling data. – ICES Journal of Marine Science, 66: 1892–1898. Fishers from Le Croisic (France) measure all the lobsters (Homarus gammarus) they capture, indicating their sex and whether the females are ovigerous or non-ovigerous. Between 2003 and 2006 and mainly between April and September, 16 884 lobsters were measured in this manner. These self-sampled data were used to study catchability and functional maturity of lobsters. The sex ratio was 50%, and catchability did not change if a female was ovigerous or non-ovigerous. With the help of a logistic function, a relationship was established between body size and the proportion of ovigerous females. For the study area, 100% of the females were mature upon reaching a carapace length (CL) of 115 mm, and the proportion of ovigerous females reached 70% each year. The L50 value evolved over a CL of 103–106 mm. From the size when 100% of the females matured (115 mm), there was a larger proportion of ovigerous females than in other studies carried out in more northern European areas.

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Phenotypic and environmental predictors of reproductive success in painted turtles

10.1101/2020.11.10.377028 ◽

2020 ◽

Author(s):

Jessica M. Judson ◽

Luke A. Hoekstra ◽

Kaitlyn G. Holden ◽

Fredric J. Janzen

Keyword(s):

Body Size ◽

Reproductive Success ◽

Mate Choice ◽

Sex Ratio ◽

Sex Ratios ◽

Female Mate Choice ◽

Painted Turtles ◽

Weak Evidence ◽

Adult Sex Ratio ◽

Siring Success

ABSTRACTSexual selection is often assumed to elicit sexually dimorphic traits. However, most work on this assumption in tetrapod vertebrates has focused on birds. In this field experiment, we assessed relationships between both sexually dimorphic (body size, claw length) and non-dimorphic traits (forelimb stripe color, baseline corticosterone concentrations) and reproductive success in adult painted turtles to explicate the roles of these phenotypes in mate choice and the evolution of sexual dimorphism. We also modified adult sex ratios in experimental ponds to elucidate the role of biased sex ratios on reproductive success, which is a timely test of the potential threat of biased sex ratios on population persistence in a species with temperature-dependent sex determination. We found no strong influence of male phenotypes on male siring success, but female body size and baseline corticosterone concentrations predicted female clutch sizes. We find weak evidence that adult sex ratio influences male siring success, with a male-biased sex ratio producing lower male siring success than a female-biased sex ratio. This study offers evidence that female mate choice may not be an important selective force on male phenotypes, but that instead selection occurs on female phenotypes, particularly body size and corticosterone concentrations. Further, biased adult sex ratios can influence reproductive success of both sexes. Finally, the use of Kompetitive Allele Specific PCR (KASP) was highly successful in parentage analysis, which adds reptiles to the growing list of taxa successfully genotyped with this new technology.Lay SummaryFemale painted turtles aren’t choosy about traits of their mates. In a field experiment, we find that male traits do not predict male fitness, but key female traits (body size and stress levels) do predict female reproductive success. Further, we find weak evidence that adult sex ratio influences individual fitness in this species with environmental sex determination. Ultimately, we reject the long-assumed importance of female mate choice in this freshwater turtle.

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Female-biased sex ratio in adults of the turtle Emys orbicularis at the northern limit of its distribution in France: a probable consequence of interaction of temperature with genotypic sex determination

Canadian Journal of Zoology ◽

10.1139/z89-182 ◽

1989 ◽

Vol 67 (5) ◽

pp. 1279-1284 ◽

Cited By ~ 17

Author(s):

J. Servan ◽

P. Zaborski ◽

M. Dorizzi ◽

C. Pieau

Keyword(s):

Sex Ratio ◽

Sex Determination ◽

Emys Orbicularis ◽

Gonad Differentiation ◽

Adult Sex Ratio ◽

Probable Consequence ◽

Genotypic Sex Determination ◽

Female Genotype ◽

Biased Sex Ratio ◽

Female Bias

Adult sex ratio in the turtle Emys orbicularis was determined in populations from seven ponds in Brenne (Indre, France). In all populations, the sex ratio was biased toward females. Among 290 captured animals, the male:female ratio was close to 0.5. Among different demographic factors that could affect the adult sex ratio, the most influential was probably the sex ratio of hatchlings. In Emys orbicularis, a ZZ male/ZW female system of genotypic sex determination has been postulated. Moreover, gonad differentiation is dependent on temperature and sex-reversed individuals can occur. To evaluate the importance of sex reversal among adult females, the blood of 78 animals was typed for the serologically detectable H-Y antigen, used as a tool to identify sexual genotype. In 73 of them, the H-Y phenotype was positive, conforming with female genotype, but in the other 5 females, it was negative (as in genotypic males), revealing that the sexual phenotype of these animals had been inverted. As the percentage of these sex-reversed genotypic males is low, the influence of temperature would appear not to be the sole cause of the observed unbalanced sex ratio. The female bias can be partly explained by the interaction of temperature with the ZZ/ZW system of genotypic sex determination. Indeed, in this system, sexual inversion under the influence of an epigenetic factor increases the ratio of genotypic females (ZW and WW) in the progeny.

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Sauropodomorph evolution across the Triassic–Jurassic boundary: body size, locomotion, and their influence on morphological disparity

Scientific Reports ◽

10.1038/s41598-021-01120-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Cecilia Apaldetti ◽

Diego Pol ◽

Martín D. Ezcurra ◽

Ricardo N. Martínez

Keyword(s):

Body Size ◽

Body Mass ◽

Late Jurassic ◽

Small Region ◽

Late Triassic ◽

Morphological Disparity ◽

Almost All

AbstractSauropodomorph dinosaurs were the dominant medium to large-sized herbivores of most Mesozoic continental ecosystems, being characterized by their long necks and reaching a size unparalleled by other terrestrial animals (> 60 tonnes). Our study of morphological disparity across the entire skeleton shows that during the Late Triassic the oldest known sauropodomorphs occupied a small region of morphospace, subsequently diversifying both taxonomically and ecologically, and shifting to a different and broader region of the morphospace. After the Triassic–Jurassic boundary event, there are no substancial changes in sauropodomorph morphospace occupation. Almost all Jurassic sauropodomorph clades stem from ghost lineages that cross the Triassic–Jurassic boundary, indicating that variations after the extinction were more related to changes of pre-existing lineages (massospondylids, non-gravisaurian sauropodiforms) rather than the emergence of distinct clades or body plans. Modifications in the locomotion (bipedal to quadrupedal) and the successive increase in body mass seem to be the main attributes driving sauropodomorph morphospace distribution during the Late Triassic and earliest Jurassic. The extinction of all non-sauropod sauropodomorphs by the Toarcian and the subsequent diversification of gravisaurian sauropods represent a second expansion of the sauropodomorph morphospace, representing the onset of the flourishing of these megaherbivores that subsequently dominated in Middle and Late Jurassic terrestrial assemblages.

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The morphometrics and colouration of the European pond turtle Emys orbicularis in Lubuskie province (West Poland)

Biologia ◽

10.2478/s11756-006-0094-9 ◽

2006 ◽

Vol 61 (5) ◽

Cited By ~ 2

Author(s):

Bartłomiej Najbar ◽

Ewa Szuszkiewicz

Keyword(s):

Endangered Species ◽

Body Mass ◽

Carapace Length ◽

Egg Laying ◽

Emys Orbicularis ◽

Straight Carapace Length ◽

Pond Turtle ◽

The Past

AbstractThe European pond turtle Emys orbicularis, is an endangered species in Poland. The region of the Ilanka River, in the western part of the country (Lubuskie province), is the most densely inhabited area by the species. Several populous sites are dispersed over the whole area of the province. Over the past 10 years, 279 turtles were captured at 11 sites. In 218 individuals, those with a straight carapace length (SCL) between 2.10–12.10 cm, sex was not determined; the remaining 61 with SCL 13.33–19.85 cm were sexed. Females had bigger bodies and were heavier than males. The SCL of females was 17.10 ± 1.7 cm (average ± SD, n = 33), their body mass (BM) was 790.6 ± 228.7 g (n = 27), and in the case of males SCL was 15.44 ± 1.5 cm and BM was 554.2 ± 138.8 g (n = 28). SCL of the smallest egg laying female was 15.30 cm, and SCL of the smallest mating male was 13.33 cm. The colouration of the turtles which undergoes change with age can be varied.

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Adult Sex Ratio in the Parnassius Mnemosyne Butterfly: Effects of Survival, Migration, And weather

Israel Journal of Ecology and Evolution ◽

10.1560/ijee.55.3.233 ◽

2009 ◽

Vol 55 (3) ◽

pp. 233-252 ◽

Cited By ~ 14

Author(s):

Petr Vlasanek ◽

David Hauck ◽

Martin Konvicka

Keyword(s):

Sex Ratio ◽

Population Size ◽

Linear Models ◽

Adult Emergence ◽

Adult Males ◽

Effective Population ◽

Weather Variables ◽

Animal Populations ◽

Adult Sex Ratio ◽

Males And Females

Sex ratio biases in animal populations influence the genetically effective population size, and thus are of interest in conservation. A butterfly group in which many authors report biases towards males is the genusParnassiusLatreille, 1804 (Papilionidae). Using a vulnerable woodland species,P. mnemosyne, we carried out a detailed marking campaign designed to eliminate biases towards individual sexes on marking. We then estimated the numbers of males and females using constrained linear models (CLMs) (Cormack-Jolly-Seber and Jolly-Seber in MARK); compared details of mobility between males and females using the Virtual Migration (VM) model; and built CLMs containing weather variables in order to directly assess weather effects on survival. The estimated population size was 4000 adults, with a male: female sex ratio of 1.5-1.6. Both daily and average catchability were higher for males, while the residence values (i.e., survival) were higher for females. Migration parameters were similar for the sexes, with slightly lower male survival within patches and slightly higher male emigration. CLMs with weather substituted for or added to marking days performed worse than models with mere marking days, and although weather affected the sexes differently, males still retained lower survival. The surplus of adult males in the studied population ofP. mnemosynewas real, not caused by increased male survival or a difference in mobility. Therefore, the bias toward males must appear prior to adult emergence, probably during the larval period.

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The louse populations of some cricetid rodents

Parasitology ◽

10.1017/s0031182000027748 ◽

1955 ◽

Vol 45 (3-4) ◽

pp. 409-420 ◽

Cited By ~ 2

Author(s):

Edwin F. Cook ◽

James R. Beer

Keyword(s):

Sex Ratio ◽

Population Size ◽

Peromyscus Maniculatus ◽

Microtus Pennsylvanicus ◽

Infestation Rate ◽

Clethrionomys Gapperi ◽

Average Population ◽

Sucking Lice ◽

Adult Sex Ratio ◽

Average Population Size

In 1952 and 1953, 798 specimens of Peromyscus maniculatus, Microtus pennsylvanicus and Clethrionomys gapperi were examined for total louse populations. Two species of sucking lice, Hoplopleura acanthopus and H. hesperomydis, were found on these species. H. acanthopus was found almost exclusively on Microtus pennsylvanicus and Clethrionomys gapperi, and Hoplopleura hesperomydis was found almost exclusively on Peromyscus maniculatus.Contamination appears to account for the apparently abnormal associations. The rates of infestation varied from host to host and from year to year. In general the higher infestations were found on host populations which were stable or declining, and the lower rates were on hosts which were increasing in density. Microtus pennsylvanicus had the highest infestation rate followed by Peromyscus maniculatus, with Clethrionomys gapperi nearly free of lice.The age of the host apparently had little to do with rate of infestation or population size.The louse populations were made up of about equal numbers of adults and nymphs. The adult sex ratio was, in each sample, unbalanced in favour of the females.The average population size varied between sexes of host and years. The male hosts had a higher average population than the female.

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