Claudio Angelini

Fatal chytridiomycosis in the tyrrhenian painted frog.

Batrachochytrium dendrobatidis (Bd), the causative agent of the amphibian disease chytridiomycosis, is an important factor in the global decline of amphibians. Within Europe, animals that exhibit clinical signs of the disease have only been reported in Spain despite the pathogen’s wide, but patchy, distribution on the continent. Recently, another occurrence of chytridiomycosis was reported in Euproctus platycephalus, the Sardinian brook newt, on the Mediterranean island of Sardinia, but without any evidence of fatal disease. We report further evidence of the emergence of Bd on Sardinia and the first evidence of lethal chytridiomycosis outside of Spain. Unusual mortalities of the Tyrrhenian painted frog (Discoglossus sardus) were found at three sites in the Limbara mountains of northern Sardinia. Molecular and histological screens of corpses, frogs, and tadpoles from these sites revealed infection with Bd. Infection and mortality occurred at locations that are unusual in terms of the published habitat requirements of the pathogen. Given the endemicity, the IUCN Red List status of the amphibian species on Sardinia, and the occurrence of infection and mortality caused by chytridiomycosis, there is serious reason for concern for the impact that disease emergence may have on the conservation of the amphibians of the island.

A multi-year and multi-site population study on the life history of Salamandrina perspicillata (Savi, 1821) (Amphibia, Urodela)

We studied nine populations of Salamandrina perspicillata for two to nine years and described the life history variation among these population. Despite experiencing similar climatic conditions, populations differed in mean body size: populations using still water bodies for oviposition were larger body-sized than those using brooks. One semi-natural pond was used by particularly small individuals and was probably recently colonised. The mean body size of ovipositing females varied from year to year. Measurements of individuals in successive years showed that the tail grew more than the trunk and this differential growth increased with age. Females did not oviposit every year and, within a given population, the number of ovipositing females varied widely from year to year.

The pandemic pathogen of amphibians, Batrachochytrium dendrobatidis (Phylum Chytridiomycota), in Italy.

Abstract Worldwide amphibian declines and species losses are global problems and emerging infectious diseases have been identified as one of the major threats. The worst of these is chytridiomycosis, an amphibian disease caused by the chytrid fungus Batrachochytrium dendrobatidis (Bd). Here we review what is known of the distribution of Bd and chytridiomycosis in Italy. We critically summarize the evidence in support of the hypothesis that Bd is an invasive pathogen in Italy. Last we provide recommendations for immediate research needs, both for basic science and applied conservation.

Image analysis of the ventral colour pattern discriminates between Spectacled salamanders, Salamandrina perspicillata and S. terdigitata (Amphibia, Salamandridae)

In the present study, we applied statistical methods to quantitative image analysis of the persistent and individual ventral colour pattern of Salamandrina salamanders, in order to discriminate between individuals of the two species belonging to this genus. Pictures of 238 individuals from three populations of S. perspicillata and pictures of 95 S. terdigitata from two populations were analysed. Partial least squares discriminant analysis (PLSDA) classified 98.78% of individuals into the correct species. PLSDA reaches lower percentages of correct classification when applied to discriminate individuals from different populations of the same species (74.14% for S. perspicillata, 78.26% for S. terdigitata). An ANOVA analysis of colour abundances in different body sectors reveals significant differences between species. The results show that colour pattern has a specific basis, the most discriminant areas being the head and the pectoral girdle. We discuss these results in the light of the proposed evolutionary scenarios of the species, and suggest that ventral colour patterns were driven by founder effect.

Capture-mark-recapture analysis reveals survival correlates in Salamandrina perspicillata (Savi, 1821)

We carried out a mark-recapture survival analysis of female Salamandrina perspicillata in two central Italian populations. Overall survival was similar in both populations (about 85-90% per year) and the estimated lifespan was about twelve years. We detected transients in one population, possibly related to the high density of females in this site. The breeding probability of females was independent from that of the preceding year.

Records of "Salamandrina perspicillata" (Savi, 1821) in the Colli Albani (Latium, central Italy), with some ecological notes (Urodela, Salamandridae)

The distribution of the Northern Spectacled Salamander in the Colli Albani (= Albani Hills), together with some ecological aspects at eight sites are reported. In four sites, oviposition took place between February and April, but in the other four it probably started at least in the first half of december. Eggs were deposited into the water of either temporary or perennial spring ponds or inside flooded man-made tuff tunnels. In some sites, which do not undergo summer drought, some larvae surpassed the summer and even the following winter. For one site, length and weight of 52 ovipositing females were recorded and larval development was monitored. A clear relation between larval body size and limb development did not appear.

Islands within an island: Population genetic structure of the endemic Sardinian newt, Euproctus platycephalus

Abstract The identification of historic and contemporary barriers to dispersal is central to the conservation of endangered amphibians, but may be hindered by their complex life history and elusive nature. The complementary information generated by mitochondrial (mtDNA) and microsatellite markers generates a valuable tool in elucidating population structure and the impact of habitat fragmentation. We applied this approach to the study of an endangered montane newt, Euproctus platycephalus. Endemic to the Mediterranean island of Sardinia, it is threatened by anthropogenic activity, disease, and climate change. We have demonstrated a clear hierarchy of structure across genetically divergent and spatially distinct subpopulations. Divergence between three main mountain regions dominated genetic partitioning with both markers. Mitochondrial phylogeography revealed a deep division dating to ca. 1 million years ago (Mya), isolating the northern region, and further differentiation between the central and southern regions ca. 0.5 Mya, suggesting an association with Pleistocene severe glacial oscillations. Our findings are consistent with a model of southward range expansion during glacial periods, with postglacial range retraction to montane habitat and subsequent genetic isolation. Microsatellite markers revealed further strong population structure, demonstrating significant divergence within the central region, and partial differentiation within the south. The northern population showed reduced genetic diversity. Discordance between mitochondrial and microsatellite markers at this scale indicated a further complexity of population structure, in keeping with male‐biased dispersal and female philopatry. Our study underscores the need to elucidate cryptic population structure in the ecology and conservation strategies for endangered island‐restricted amphibians, especially in the context of disease and climate change.

Survival and recruitment in the population ecology of the endangered Bombina pachypus (Amphibia: Anura)

Global amphibian decline is a subject of great conservation concern, yet often basic demographic information is absent, which prevents the understanding of population trends and the planning of effective conservation management. We analysed capture-mark-recapture data from six populations of the endangered Bombina pachypus in order to understand the relative contribution of survival and recruitment to population growth, and to assess if any differences exist among populations in terms of their population dynamics. We found that survival was rather high and generally constant among sites, and recruitment was low, with the exception of two single years at one site. Population growth depended on survival on all sites, except the years following high recruitment at one site. Annual population size was generally lower than 30 individuals, but in one site it was estimated to be larger than 50. Our findings suggest that juvenile survival is more important for population dynamics than recruitment from the larval to the juvenile stage. We also suggest that the low recruitment rates we recorded was a result of juvenile dispersal, and that when populations exhibited high recruitment it was due to occasional successful migration or local recruitment. This pattern could represent a way to counterbalance the risk of inbreeding in populations composed of few individuals, a common characteristic of populations of B. pachypus . Finally, we suggest that conservation measures for B. pachypus should be planned at the landscape scale, and should not be limited solely to the breeding site and its close surroundings.