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We studied age at maturity, longevity, and growth in a marbled newt (Triturus marmoratus) population in southwestern France. Parameters of the life cycle such as date of migration, reproductive period, and terrestrial activity were documented for three neighbouring temporary ponds. This Mediterranean marbled newt population was characterized by aestivation and hibernation periods, a prolonged aquatic phase in adults, and a presence of juveniles in water. Aestivation and hibernation lead to distinct growth periods as determined by skeletochronology. Minimum age at maturity was 2 and 3 years, whereas maximum age observed was 8 and 9 years in males and females, respectively. A higher growth rate and a lower survival rate were found in this Mediterranean population compared with other populations exposed to variable environmental conditions in western Europe.

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.

Changes in age structure of local populations were analyzed to determine the migrations of adult crested newts (Triturus cristatus) in a network of ponds. An individual's age was estimated by applying a skeletochronological method to the phalanges. The local populations studied bred in four neighbouring cattle ponds, the distance between any two of which did not exceed 150 m. These ponds belong to the larger network. Though the size of the whole population doubled from one year to the next, one local population became extinct due to lack of recruitment of young breeders. The larger local population attracted not only young breeders but also older newts, which probably came from other ponds. In ponds inhabited by fish, the newts were mainly young animals (2–3 years old), suggesting that they leave such ponds after their first breeding season. The results are discussed with regard to the model proposed by Gill for metapopulations of Notophthalmus viridescens. In the crested newt, contrary to Gill's predictions, all the sites do not recruit young breeders, and fidelity to the breeding site may be broken. The two species differ in longevity and age at maturity, hence it is suggested that functional models of metapopulations must integrate life-history parameters.