On 13th June 2014 we observed one population of Alpine newt (Ichthyosaura alpestris) outside its natural distribution range, near the natural space of "Parc del Castell de Montesquiu" in Barcelona, Catalonia Spain. This finding represents the first report of a breeding population of I. alpestris in Catalonia. On 18th and 25th June, we performed two samplings with the aim of: a) determining whether nearby water ponds were colonized, b) estimating population size, c) performing population biometrics, d) determining the origin of the introduced specimens, and e) detecting the presence of pathogens in the population. After doing molecular analyses, we found out that the introduced might be a mix of individuals from two different subspecies: I. a. apuanus and I. a. cyreni. Interestingly, these subspecies are commonly used in aquariums. We detected the presence of Ranavirus spp in the studied individuals, thus increasing the risk of transmission to native species, such as Alytes obstetricans. Additionally, we also observed the presence of two other breeding populations of I. alpestris near the study area, which might be a direct consequence of their invasive potential. We concluded that a drastic intervention is highly needed to prevent the expansion of I. alpestris and remove the species from this area.
Fibla M, Ubach A, Oromí N, Montero-Mendieta S, Camarasa S, Pascual-Pons M, Martínez-Silvestre A & Montori A. (2015) Población introducida de tritón alpino (Mesotriton alpestris) en el Prepirineo catalán. Bol. Asoc. Herpetol. Esp: 26(1) [PDF]