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Context: Increasing the amount of green infrastructure, defined as small-scale natural landscape elements, has been named as a climate adaptation measure for biodiversity. While green infrastructure strengthened ecological networks in some studies, it is not known whether this effect also holds under climate change, and how it compares to other landscape adaptation options. Objectives: We assessed landscape adaptation options under scenarios of climate change for a dispersal-limited and climate-sensitive species: great crested newt, Triturus cristatus. Methods: A spatially-explicit modelling framework was used to simulate newt metapopulation dynamics in a case study area in the Netherlands, under alternative spatial configurations of 500 ha to-be-restored habitat. The framework incorporated weather-related effects on newt recruitment, following current and changing climate conditions. Results: Mild climate change resulted in slightly higher metapopulation viability, while more severe climate change (i.e. more frequent mild winters and summer droughts) had detrimental effects on metapopulation viability. The modelling framework revealed interactions between climate and landscape configuration on newt viability. Restoration of ponds and terrestrial habitat may reduce the negative effects of climate change, but only when certain spatial requirements (habitat density, connectivity) as well as abiotic requirements (high ground water level) are met. Conclusions: Landscape scenarios where habitat was added in the form of green infrastructure were not able to meet these multiple conditions, as was the case for a scenario that enlarged core areas. The approach allowed a deduction of landscape design rules that incorporated both spatial and abiotic requirements resulting in more effective climate adaptation options.

International audience; We describe the life-history traits (body size, age at maturity, longevity, and survivorship) of a terrestrial salamander, Mertensiella luschani, from a population living in the Mediterranean environment of southwestern Turkey. We used phalangeal skeletochronology to estimate the age of juveniles and adults. Lines of arrested growth, deposited during the winter cessation of bone growth, allowed us to estimate the age at maturity to be 3 years old in both sexes. Males attained a maximum age of 8, whereas females attained a maximum age of 10. Juveniles ranged from 1 to 3 years old. Males were smaller than females. Growth curves fitted to von Bertalanffy's equation revealed similar growth coefficients in adults and larger average maximum body lengths in males. Adult annual survivorship and adult life expectancy were 0.79 and 5.4 years, respectively. Knowledge of age, growth, and survivorship in this species under the constraints of a seasonal Mediterranean climate, and a comparison of similar traits in other salamandrid species, allow us to test predictions regarding optimal timing of growth and reproduction in these species.

International audience; We describe the age structures of two neighbouring terrestrial salamander populations. The skeletochronological method was also used on larvae in utero and on new-born individuals. The age of adults was 8-24 years in population A, while males reached maturity at 3-5 years old and the youngest females were 6 years old in population B. Males and females from population B were also larger than those in population A. For the first time, lines of arrested growth (LAGs) were also found in the humerus of intra-uterine larvae and new-born individuals, indicating that young can spend up to 3 years in utero (population B) and up to 4 years (population A) before hatching. Growth of adults (fitted by the Bertalanffy model) also exhibited differences in growth coefficient (k) and mean asymptotic length (SVLmax) between sexes and populations. Local climatic conditions differed between the two areas of these populations and we hypothesize that the number of rainy days directly influences foraging during the short period of activity (< 3 months), leading to a delay in age at maturity, smaller length and growth rate, and increased gestation duration in the drier environment. The discussion is focused on proximate environmental influences on the variation of length and associated life-history traits in ectotherms, especially in terrestrial salamanders.

ISI Document Delivery No.: 821GR Times Cited: 6 Cited Reference Count: 14 English Article 0268-0130; International audience; This study describes a non-destructive DNA sampling method for genetic studies on amphibians using buccal swabs. We assessed the quantity and quality of DNA collected in each species by amplifying a part of the cytochrome b gene (381-1060 bp) and microsatellite markers. Buccal swab sampling is a useful alternative method for DNA sampling for both mtDNA and nDNA markers in amphibians. However, only frozen storage allowed microsatellite genotyping. We conclude that this method could greatly increase the accessibility of genetic studies in small vertebrates and could be preferred in the field of conservation genetics.

International audience; Age structure of a Pelobates fuscus population portion, which visits ponds during the 1996 breeding period, was studied using skeletochronological methods. The studied population lives in northeast France, in the western border of the species area. The age distributions were strongly different between the sexes: males were represented mainly by the two- and three-year-old individuals, when females were older. A lack of three-year-old migrating females was observed and discussed.

1. We have used a stochastic population model with immigration to calculate extinction rates for two amphibian species: the common toad, Bufo bufo, and the crested newt, Triturus cristatus. 2. Population models for amphibians are difficult to parameterize. It was not possible to measure all the relevant parameters for the model. The other parameters were obtained from other studies or estimated on the basis of similar species. 3. Contour maps for persistence were generated using the model. The persistence of populations associated with a pond is affected both by the pond's internal dynamics and its proximity to a source pond. On a 20-generation time scale, toad ponds that were initially occupied were relatively unaffected by the proximity of a source. Persistence was almost certain (>95%) when the average carrying capacity of a pond was greater than 30 adult females. Initially unoccupied toad-ponds were equally likely to persist if they lay within 4 km of a source and could support more than 50 adult females. Initially occupied newt ponds were likely to persist if they supported more than 40 females or lay within 0.5 km of a typical source pond. Initially unoccupied newt ponds were mainly dependent upon immigration rates. Very small ponds (N-k