Sardinian geotritons are endemic amphibians closely associated with cool and humid environments, including caves, rock crevices, artificial cavities and limestone outcrops. Their often fragmented distribution, limited dispersal ability and strong dependence on microclimatic conditions make these species particularly sensitive to environmental change and climate change.
The project aims to develop reliable protocols for monitoring Sardinian populations of the genus Speleomantes, with particular attention to Speleomantes sarrabusensis, an endemic species of south-eastern Sardinia classified as Critically Endangered.
Research activities are based on repeated surveys of cavities and rocky habitats used by geotritons, together with measurements of temperature, humidity and habitat characteristics. Because the probability of observing individuals changes considerably throughout the year, monitoring design must account for seasonality and microclimatic conditions.
Studies co-authored by Leonardo Vignoli on Speleomantes italicus provide important ecological and methodological foundations that can be applied to the monitoring of Sardinian geotritons. This research showed that activity and occurrence inside cavities follow marked seasonal patterns, are influenced by temperature and humidity, and vary between areas close to cave entrances and deeper sectors.
Research on the spatial niche of Speleomantes italicus identified a peak in activity between spring and summer and a relationship between observed abundance and thermal conditions. During summer, cavities may provide essential refuges when external conditions become incompatible with the physiological requirements of geotritons. Adults may also use areas closer to cave entrances more frequently when the external microclimate is favourable.
Research on the trophic niche showed that subterranean populations can feed during much of the year, although feeding activity is discontinuous and linked to seasonal prey availability. Lower food availability inside cavities may result in a narrower trophic niche than in populations making greater use of surface habitats.
These findings indicate that counts conducted during a single season or under non-comparable microclimatic conditions may provide unrepresentative estimates. Monitoring Sardinian geotritons should therefore include repeated visits, systematic recording of environmental conditions and surveys conducted during comparable periods.
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