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Behavioral adaptation is one of the first responses put in play by individuals to buffer environmental variations and to maintain homeostatic equilibrium with their environment. Microhabitat selection is pivotal for maximizing fitness, survival and reproduction, but how individuals process and exploit information acquired from the environment to make future microhabitat choice is yet understudied. In this study, we used outdoor mesocosms in which we introduced Strinati's cave salamanders (Speleomantes strinatii), to assess their behavioral patterns of shelter site fidelity. In each mesocosm three microhabitats were available to the salamanders: the leaf litter, a log and a rock. A total of 22 salamanders were tested over an 8-day period, 11 in autumn and 11 in spring. Salamanders shelter site fidelity was driven by both microhabitat humidity and previous experience obtained in the mesocosm. In our experiment, the time spent in the mesocosm was the main factor influencing shelter site fidelity, suggesting that previous experience and familiarity are important in salamanders' behavioral adaptation. Therefore, cave salamanders are capable of learning from experience when selecting their shelters, a behavior that could also be relevant during migration, colonization of new environments and adaptation to climate change. Highlights: How individuals exploit information gained from experience to select a microhabitat is understudied We found that plethodontid salamanders are capable of exploiting information on their environment to select the most suitable microhabiat [ABSTRACT FROM AUTHOR]

Long-term effects of current climate on animal populations living in subterranean habitats are still poorly understood. In this study, we analyzed the variability of the demographic structure and abundance of a population of terrestrial plethodontid Strinati's Cave Salamanders (Speleomantes strinatii) (Aellen, 1958) living inside a northwestern Italian artificial cave over 27 yr from 1996 to 2022. The study site is situated in the Northern Apennines, where average air temperatures measured at two local weather stations were steadily increasing, whereas precipitation was relatively constant over the past 60 yr. Our objective was to evaluate whether the demographic traits of the population of Strinati's Cave Salamanders were showing detectable signs of directional shift during the 27 yr. Each year in July, the population abundance was estimated by a three-occasion removal experiment, salamanders' snout–vent length (SVL) was measured, and the population polymodal body-size distribution was decomposed into estimated age classes. The annual population abundance, adult sex ratio, recruitment, SVL, and growth increments of first- and second-year immature salamanders were analyzed. The Strinati's Cave Salamander time series was modeled by autoregressive moving average (ARMA) analysis, and demographic parameters were tested for temporal trends. There were no directional trends observed in any of the demographic parameters of the focal cave salamander population over the study period. The best autoregressive model describing the population variation was an ARMA (2,1). Results indicated that the salamander population had a complex fluctuating pattern in which the interaction of lagged density dependence and an external autocorrelated factor were influencing the population long-term dynamics. Our findings suggest that the population of this long-lived salamander species was probably buffered from external conditions by the thermal inertia of its subterranean habitat that is known to delay and reduce the amplitude of aboveground climatic signals. [ABSTRACT FROM AUTHOR]

Boldness is a personality trait defined as the propensity of an animal to engage in risk-taking behaviours. Boldness is often associated with social ranking, dispersal, movement, and home range in many animal species. In this study we tested if boldness was correlated with individual spatial behaviour, in a population of the Cave Salamander Speleomantes strinatii living in a subterranean habitat. Boldness was measured in a controlled environment by means of an emerging from a shelter trial, while home ranges and distances moved over two years were obtained in the wild from a spatially explicit capture-mark-recapture study. We obtained data from 13 salamanders that were captured at least 5 times (mean 7.23; range 5-11). As expected, there was a highly significant and negative correlation between individual risk taking behaviour and home range overlap with conspecifics (rs = 0.84; p = 0.005). This pattern could be explained by differences in habitat physical quality or in its available resources, but more research is needed to better understand this behavioural pattern. [ABSTRACT FROM AUTHOR]

The article discusses the increasing spread of zoonotic diseases from animals to humans due to human pressures on natural environments and wildlife populations. Factors such as habitat degradation, pollution, climate change, and international animal trade contribute to the loss of ecological function and ecosystem resilience. The presence of wildlife in urban areas poses a significant risk of zoonotic disease transmission, highlighting the need for proactive measures to reduce health risks and conflicts between humans and wildlife in urban settings. The study emphasizes the importance of educating urban residents about wildlife interactions and ecosystem functions to mitigate the spread of zoonoses. [Extracted from the article]

Amphibians are small ectothermic vertebrates with high permeable skins that are highly constrained by environmental conditions, such as humidity and temperature. Therefore, terrestrial salamanders regulate their surface activity, including foraging, to minimize evaporative water loss. The influence of local micro-climatic factors on the foraging success of European forest dwelling salamanders has rarely been analysed in detail. We examined the role of local climatic conditions on the foraging success, measured by the total number of prey items, of two syntopic forest-dwelling salamanders: Strinati's cave salamander, Speleomantes strinatii (family Plethodontidae), and Northern spectacled salamander, Salamandrina perspicillata (family Salamandridae). We evaluated the effects of rainfall, temperature and body size on the foraging success of these two species, in eight sampling sites in the Northern Apennines of Italy, for a total of 11 salamander populations. Our findings show that different climatic variables affected the two species differently. Salamandrina perspicillata foraged more intensively during periods of prolonged rainfall with higher temperatures. On the contrary, S. strinatii foraging success was negatively influenced by rising temperature, while rainfall seemed to have no significant effect. Interestingly, body size increased success in S. perspicillata but not in S. strinatii. Overall, our findings show that, when foraging in the same environment, these two species are conditioned by different climatic factors possibly due to their differences in overall body size and their ability to resist dehydration. [ABSTRACT FROM AUTHOR]

Information on individual trophic specialization may be relevant to better understand the ecological adaptation of populations to their environment and the evolution of their realized trophic niche. In this study, we analysed the trophic specialization at the individual level in a population of the plethodontid Northwest Italian Cave Salamander (Speleomantes strinatii (Aellen, 1958)), a terrestrial generalist predator. Salamanders were sampled in northwestern Italy on the forest floor in autumn (n = 49) and spring (n = 47) along with their available prey. In autumn, when trophic resources showed a twofold reduction in abundance, the population trophic niche width (TNW = 2.58) was significantly broader than during spring (TNW = 2.25), and in both seasons, individual specialization (IS) was significantly higher than expected by chance (P = 0.001). There were no sexual or ontogenetic differences in IS within each season, but IS in autumn was significantly higher than in spring (IS = 0.34 and IS = 0.41, respectively; P = 0.01). These findings are in accordance with the niche variation hypothesis, which predicts a positive relationship between TNW and IS. Therefore, while the population became more generalist, individual salamanders shifted towards a more specialized diet by adapting their feeding behaviour to changes in prey availability. Key words: Northwest Italian Cave Salamander, trophic ecology, individual specialization, Speleomantes strinatii, trophic behaviour, trophic niche variation. La connaissance de la specialisation trophique a niveaux individuelle peut permettre de mieux comprendre l'adaptation des populations a leur milieux et revolution de leur niche trophique realisee. Dans cette etude, nous avons analyse la specialisation trophique individuelle dans une population de la salamandre terrestre Speleomantes strinatii (Aellen, 1958), qui est un predateur generaliste. Nous avons echantillonnees les salamandres, au meme temps que leur disponibilite en proies, en un milieu forestier de l'Italie du nord-ouest, au cours de l'automne (n = 49) et du printemps (n = 47). En automne, quand la disponibilite en proies est reduite, l'ampleur de niche trophique de la population est majeure (TNW = 2,58) qu'au printemps (TNW = 2,25). Toutefois, dans les deux saisons, la specialisation individuelle (IS) est significativement majeur de celle attendue par chance (P = 0,001). Il n'y a pas des differences de specialisation trophique individuelle a niveau du sexe ou d'age entre saison, mais en automne l'IS est majeur qu'au printemps (respectivement IS = 0,34 et IS = 0,41, P = 0,01). Ces resultats sont en accord avec l'hypothese de la variation de niche, la quelle predit une relation positive entre TNW et specialisation a niveau individuel. Dans notre cas, lorsque la population entiere devienne plus generaliste, les individus assument une diete plus specialisee en s'adaptant aux changement des proies disponibles. Mots-cles: Spelerpes de Strinati, ecologie trophique, specialisation individuelle, Speleomantes strinatii, comportement trophique, variation de la niche trophique., Introduction Generalist predators are those that consume a high diversity of prey resources, usually in proportions similar to those available in the environment, whereas specialists feed on a restricted array [...]

The salamander killing fungus Batrachochytrium salamandrivorans (Bsal), recently introduced from Asia, is threatening salamander populations in different parts of Europe. In fact, this pathogen is rapidly spreading in Central Europe and has been also introduced into NE Spain. Of special concern are those regions with an exceptionally high salamander diversity such as Italy, where 19 salamander species are present most of which are strictly endemic. In this study, we update the information on the presence of Bsal in Italian wild salamanders, by adding samples from two presumptive outbreak sites, one on the island of Sardinia and one on continental Italy (Liguria). In addition, we reviewed the potential susceptibility of all the Italian salamander species on the basis of laboratory experimental infection trials, or from the tested susceptibility of the phylogenetically nearest species, according to the literature. Overall, 15 skin swabs from three species (Speleomantes sarrabusensis, Speleomantes strinatii and Salamandra salamandra) collected in the two presumptive Bsal outbreak sites were analysed by quantitative molecular methods, but none gave positive results. The majority of Italian salamander species and almost all of the endemic ones showed a high susceptibility to Bsal infection. Therefore, even if the presence of Bsal in Italian salamander populations has not been proven yet, the entire salamander fauna is highly threatened and preventive management actions should be taken. The need for strict biosecurity protocols on the international trade of captive or wild amphibians and for the implementation of preventive measures during field activities to limit the introduction and spread of the Bsal pathogen is again stressed. [ABSTRACT FROM AUTHOR]