Daily activity patterns and food preferences in an alpine ant community

Species may reduce competitive interactions by temporal separation in activity times. Similarly to other animals, ants also partition their niches by being active during specific periods of the year or at specific times of the day. However, if several species share the same temporal niches, interspecific competition may give rise to behavioural dominance hierarchies, territoriality or spatial mosaics. Thus, our first aim was to study daily activity patterns of alpine communities to investigate their temporal dynamics at both general and specific levels. Due to short distances among different ecosystems, montane systems are ideal models to study the effect of geographic variation on community structure. On the other hand, ants represent an excellent model to analyze beta-diversity because they are one of the most ecologically significant components of many ecosystems. Nevertheless, there is a lack of ecological studies on ant communities in Italy and, in particular, on alpine ants. Therefore, the second aim of this work was to study ant species richness and distribution in order to update information on alpine ant fauna. As ants can simultaneously exhibit multiple trophic roles, assessing the feeding habits of an ant community may help to clarify how these insects can influence their ecosystem. Thus, the third aim of this research was to evaluate ant food preferences in alpine environments. Samplings were conducted in Soana Valley, inside the Gran Paradiso National Park, during summer 2011: pitfall traps and food baits were placed in order to collect data on species richness, abundances and food preferences. The acquired results on activity patterns showed that ants were more active in the late morning. The analysis of food preferences revealed that sugary solutions were the favourite resources. Finally, concerning species spatial distribution, there was a higher level of biodiversity at intermediate elevations, probably due to an increase of temperature and spatial heterogeneity.