Competition may lead to changes in a species’ environmental niche in areas of sympatry and shifts in the niche of weaker competitors to occupy areas where stronger ones are rarer. Although mainland Mediterranean (Rhinolophus euryale) and Mehely’s (R. mehelyi) horseshoe bats mitigate competition by habitat partitioning, this may not be true on resource-limited systems such as islands. We hypothesize that Sardinian R. euryale (SAR) have a distinct ecological niche suited to persist in the south of Sardinia where R. mehelyi is rarer. Assuming that SAR originated from other Italian populations (PES) – mostly allopatric with R. mehelyi – once on Sardinia the former may have undergone niche displacement driven by R. mehelyi. Alternatively, its niche could have been inherited from a Maghrebian source population. We: a) generated Maxent Species Distribution Models (SDM) for Sardinian populations; b) calibrated a model with PES occurrences and projected it to Sardinia to see whether PES niche would increase R. euryale’s sympatry with R. mehelyi; and c) tested for niche similarity between R. mehelyi and PES, PES and SAR, and R. mehelyi and SAR. Finally we predicted R. euryale’s range in Northern Africa both in the present and during the Last Glacial Maximum (LGM) by calibrating SDMs respectively with SAR and PES occurrences and projecting them to the Maghreb. R. mehelyi and PES showed niche similarity potentially leading to competition. According to PES’ niche, R. euryale would show a larger sympatry with R. mehelyi on Sardinia than according to SAR niche. Such niches have null similarity. The current and LGM Maghrebian ranges of R. euryale were predicted to be wide according to SAR’s niche, negligible according to PES’ niche. SAR’s niche allows R. euryale to persist where R. mehelyi is rarer and competition probably mild. Possible explanations may be competition-driven niche displacement or Maghrebian origin.
Wildlife Research Unit, Dipartimento di Agraria, Università degli Studi di Napoli Federico II, Portici, Napoli, Italy;School of Biological Sciences, University of Bristol, Bristol, United Kingdom;EnvixLab, Dipartimento Bioscienze e Territorio, Università del Molise, Pesche, Italy;School of Biological Sciences, University of Bristol, Bristol, United Kingdom;CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do Porto, University of Porto, Vairão, Portuga;Centro per lo studio e la protezione dei pipistrelli in Sardegna, Sassari, Italy;Forestry and Conservation, Cassino, Frosinone, Italy;Museo di Storia Naturale dell’Università di Firenze, Sezione di Zoologia ‘La Specola’, Firenze, Italy;Wildlife Consulting, Palo del Colle, Bari, Italy;Unità di Analisi e Gestione delle Risorse Ambientali, Guido Tosi Research Group, Dipartimento di Scienze Teoriche e Applicate, Università degli Studi dell’Insubria, Varese, Italy;Dipartimento di Scienze Mediche Veterinarie, Università degli Studi di Bologna, Ozzano dell’Emilia, Bologna, Italy;Studio Naturalistico Hyla snc, Tuoro sul Trasimeno, Perugia, Italy;Wildlife Research Unit, Dipartimento di Agraria, Università degli Studi di Napoli Federico II, Portici, Napoli, Italy
Recommended Citation:
Danilo Russo,Mirko Di Febbraro,Hugo Rebelo,et al. What Story Does Geographic Separation of Insular Bats Tell? A Case Study on Sardinian Rhinolophids[J]. PLOS ONE,2014-01-01,9(10)