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A population of Northern crested newts, Triturus cristatus, was studied for 19 consecutive years (1998-2016) using individual recognition allowing the quantification of population dynamics and survival rates. Starting with a relatively high estimated number of adults (251 ± 55) and a long stable phase (144 ± 25) the population dropped six-fold (39 ± 10) by the end of the study. The population failed to recruit in nine years including a reproduction failure over four consecutive years of the 19-year study period. The yearly adult survival ranged from 18 to 98% with no differences between the sexes. Likely related to relative favourable survival rates of individuals older than 4+ of age and adult longevity of more than 16 years the population persisted. More long-term studies are urgently needed to assess how population dynamics are subject to local environmental factors or demographic patterns of the population itself. [ABSTRACT FROM AUTHOR]

In the recently published New Atlas of Amphibians and Reptiles of Europe (Sillero et al., 2014a), the distribution of the newt genus Triturus was not resolved at the level of the species. The main reason for this was the lack of high quality distribution data from in and around the parapatric contact zones between species, where interspecific hybridization occurs. We are working extensively on Triturus and the (particularly genetic) data we have accumulated allow us to map the individual Triturus species at the appropriate scale. We here provide a database composed of distribution data for the individual species, at generally high resolution, particularly from in and around contact zones. Based on this database we produce maps at the 50 x 50 km UTM grid resolution as used in the new atlas and highlight those grid cells in which more than one Triturus species occurs. [ABSTRACT FROM AUTHOR]

We review the natural occurrence of tail duplications and tail bifurcations in amphibians as well as experimental studies that induced tail duplications. For natural populations, we found 10 publications that mention tail duplications or bifurcations in a total of 24 individual larval amphibians belonging to 15 species, mainly from Europe and South America. Nineteen publications describe the incidence for 34 individual postlarval urodeles from 12 species from North America, Europe, and Asia. Here we add three new observations: a subadult female Triturus dobrogicus with a duplicated tail and an adult female Triturus carnifex with a bifurcated tail from Hungary, and a tadpole of Hyla arborea with a bifurcated tail tip from Greece. The causes of tail duplications in wild amphibians remain unknown. Similar tail anomalies have been obtained in the laboratory when parts of the chorda dorsalis were destroyed, when tar is injected into the tail, or when the lumbar region is irradiated. [ABSTRACT FROM AUTHOR]