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N-mixture models usually rely on a meta-population design, in which repeated counts of individuals in multiple sampling locations are obtained over time. The time-for-space substitution (TSS) in N-mixture models allows to estimate population abundance and trend of a single population, without spatial replication. This application could be of great interest in ecological studies and conservation programs; however, its reliability has only been evaluated on a single case study. Here we perform a simulation-based evaluation of this particular application of N-mixture modelling. We generated count data, under 144 simulated scenarios, from a single population surveyed several times per year and subject to different dynamics. We compared simulated abundance and trend values with TSS estimates. TSS estimates are overall in good agreement with real abundance. Trend and abundance estimation is mainly affected by detection probability and population size. After evaluating the reliability of TSS, both against real world data, and simulations, we suggest that this particular application of N-mixture model could be reliable for monitoring abundance in single populations of rare or difficult to study species, in particular in cases of species with very narrow geographic ranges, or known only for few localities.

Recently several projects have been implemented for the conservation of the European turtle Emys orbicularis, but few aspects of the captive-bred animals released into the wild have been described. In this note we report about the trophic habits of a small restocked population of the endemic subspecies E. o. ingauna that is now reproducing in NW Italy. Faecal contents from 25 individuals (10 females, 11 males and 4 juveniles) were obtained in June 2016. Overall, 11 taxonomic categories of invertebrates were identified, together with seeds and plant remains. Plant material was present in 24 out of 25 turtle faecal contents, suggesting that ingestion was deliberate. There were no differences between the dietary habits of females and males, and the trophic strategy of adult individuals was characterised by a relatively high specialization on dragonfly nymphae. These findings suggest that captive bred turtles are adapting well to the wild and that restocked individuals assumed an omnivorous diet, a trophic behaviour typical of other wild turtle populations living in similar habitats., Acta Herpetologica, Vol 13 No 1 (2018)

In the Mediterranean environments forest fires have played a main role in landscape dynamic. However, especially in protected areas, uncontrolled forest fires can severely affect structural and functional ecosystem characters. The “Cilento e Vallo di Diano” National Park (PNCVD) is supporting a project to use “prescribed burning” to prevent large forest fires. We report the preliminary results on methodologies and the sampling techniques used to assess short-term effects of prescribed burning on herpetofauna inside an experimental area in the (PNCVD). Seven specie were found in the study area: Podarcis siculus, Lacerta bilineata, Anguis fragilis, Chalcides chalcides, Hierophis viridiflavus, Zamenis lineatus, and Bufo bufo. Drift fences associated with pitfall traps in two plots (burned and unburned control area) seem to be the best method to estimate population size of the more common species (P. siculus and C. chalcides). However, since these species have low densities in the study areas, replicated treatment and control plots will be needed to obtain robust results.

International audience; A continental population of the European leaf-toed gecko (Euleptes europaea) was studied from 1996 to 2000 in Central Liguria (NW Italy), to obtain data on demography, abundance and population trends. Each year in July, three night mark-recapture sessions were carried out to obtain data on population structure and abundance. The population structure of the European leaf-toed gecko was assessed on the basis of polymodal body-size frequency distributions, and the demographic structure was characterized by three well-separated size groups: juveniles ending their first year of life, subadults in their second year and mature individuals aged three or more. Growth appeared constant during the first two years, and then apparently decreased in the third year when functional sexual maturity was achieved in both sexes. The sex ratio of the reproductive population did not differ from unity and females were, on average, 5% larger than males. The physiological status of different age groups, assessed by a body condition index, did not show significant variations during the study. The observed stability of overall population size highlights the capacity of small and completely isolated colonies of the European leaf-toed gecko to persist for a long time, even in extremely simple habitats. However, the number of breeding adults showed large fluctuations, from 120 to 50 animals in different years, and count data suggested a downward trend in population size. Nevertheless, the statistical power of not reject ing the null hypothesis of "no change" (i.e.Type II error) was low, and a Monte Carlo simulation analysis showed that doubling the monitoring effort (i.e. 10 annual surveys with 30 sampling occasions) should be sufficient to detect a 10% decrease in population size with a power of >0.80. Without detailed population data from such intensive monitoring, isolated populations of E. europaea remain exposed to a high risk of extinction through stochastic and anthropogenic processes.

International audience

We studied population size and age structure of the sand lizard Lacerta agilis Linnaeus 1758, from northwest Italian Alps. Twenty-nine (9 males, 15 females, 5 juveniles) and 19 (8 males, 5 females, 6 juveniles) lizards were captured in 2011 and 2012, respectively. Adult population size, estimated by capture-markrecapture, was 54 individuals in 2011 and 39 in 2012. Mean SVL did not significantly differ between males sampled in the two years of the study (mean ± SD, 2011: 67.1 ± 6.6 mm; 2012: 61 ± 8.7 mm). On the contrary, females sampled in 2011 were significantly larger (73 ± 7.2 mm) than females of 2012 (61 ± 7.4 mm). Adult age, assessed by skeletochronology, ranged 2-5 years both in males and females. All juveniles were one-year old. In both years of sampling there was no significant difference in mean age between the sexes. Males were represented mainly by three and four-year old individuals in 2011 and by two-year old individuals in 2012. Females were represented mainly by three -year old individuals in 2011 and by two-year old individuals in 2012. However, age distribution of adults did not differ for each sex as well as between the sexes both in 2011 and 2012. Although our results showed that the examined population of L. agilis has a stable demographic structure, it should be considered seriously vulnerable, because it is relatively isolated from other neighboring populations, has small absolute size and, therefore, may be highly exposed to negative effects of habitat degradation.

The two endemic Italian brown frog species, Rana latastei and R. italica, have a very similar morphology: the diagnostic characters are the tympanum, larger in R. latastei and the nostril distance that is almost equal to the interorbital length in R. latastei, while is slightly greater in R. italica. The most important parameter in order to discriminate between the two species is their different areals: R. latastei is mostly widespread in the Po Valley, while R. italica inhabits almost only the Apennine rivers. The S1 satellite DNA from Palaearctic brown frogs displays a different structure in all the previously tested species, and this complete species- specificity was verified also for R. latastei and R. italica. Southern Blot of DNA samples from the two species, digested with five different restriction enzymes, displays different patterns of hybrid bands. Both species present two repetitive units S1a and S1b. The S1a repetitive unit has the same size but different restriction sites, while the S1b unit differs both in size and restriction sites. In conclusion, the S1 satellite DNA is a powerful molecular marker in order to discriminate the Palaearctic brown frog species.

A repeated DNA sequence, named RepHv-390, isolated from DNA samples of male and female specimens of the European Western wipe snake, Hierophis viridiflavus, was used as probe for FISH analysis to detect its distribution on chromosomes of this colubrid species and of other species of the same and of different snake families. We observed positive results in all the studied species, namely: H. viridiflavus, Coronella austriaca, Elaphe quatuorlineata (Colubridae), Phisalixella variabilis (Lamprophiidae) and Vipera aspis (Viperidae). Intense and abundant hybridization signals of RepHv-390 were observed on all chromosomes of H. viridiflavus, C. austriaca, E. quatuorlineata and V. aspis and on nuclei of P. variabilis. Its wide presence on the chromosomes of all the studied species suggests that RepHv-390 is a segment of transposable element (TE) of ancient origin in snakes. Probably, the ancient TE arose in a common Colubroidea ancestor before the diversification into different lineages of this superfamily. Preliminary analysis of RepHv-390 evidenced no significant identity with any other known sequence, suggesting that RepHv-390 is a segment of an unclassified TE element