Isotopic Overlap of Invasive and Native Consumers in the Food Web of Lake Trasimeno (Central Italy)
Davide Cicala,
Maria Teresa Guerra,
Roberta Bardelli,
Cristina Di Muri,
Alessandro Ludovisi,
Salvatrice Vizzini,
Giorgio Mancinelli
Affiliations
Davide Cicala
Department of Biology, University of Rome Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy
Maria Teresa Guerra
Department of Biological and Environmental Sciences and Technologies—DiSTeBA, University of Salento, SP Lecce-Monteroni, 73100 Lecce, Italy
Roberta Bardelli
Department of Earth and Marine Sciences—DiSTeM, University of Palermo, Via Archirafi 22, 90133 Palermo, Italy
Cristina Di Muri
Italian National Research Council, Institute of Research on Terrestrial Ecosystems—CNR-IRET, University of Salento, SP Lecce-Monteroni, 73100 Lecce, Italy
Alessandro Ludovisi
Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy
Salvatrice Vizzini
Department of Earth and Marine Sciences—DiSTeM, University of Palermo, Via Archirafi 22, 90133 Palermo, Italy
Giorgio Mancinelli
Department of Biological and Environmental Sciences and Technologies—DiSTeBA, University of Salento, SP Lecce-Monteroni, 73100 Lecce, Italy
An advanced characterization of the trophic niche of non-indigenous species (NIS) may provide useful information on their ecological impact on invaded communities. Here, we used carbon and nitrogen stable isotopes to estimate pairwise niche overlaps between non-indigenous and native consumers in the winter food web of Lake Trasimeno (central Italy). Overall, a relatively low pairwise overlap of isotopic niches was observed between NIS and native species. The only exception was the Louisiana crayfish Procambarus clarkii, which showed a relatively high and diffuse overlap with other native invertebrates. Our findings highlighted a high niche divergence between non-indigenous and native species in Lake Trasimeno, suggesting a potentially low degree of interspecific competition that may facilitate coexistence and, in turn, limit the strength of impacts. The divergent results obtained for the Louisiana crayfish indicate that additional control measures for this invasive species are needed to mitigate its impact on the Lake Trasimeno system.
