TY - JOUR A1 - Dammhahn, Melanie A1 - Rakotondramanana, Claude Fabienne A1 - Goodman, Steven M. T1 - Coexistence of morphologically similar bats (Vespertilionidae) on Madagascar: stable isotopes reveal fine-grained niche differentiation among cryptic species JF - Journal of tropical ecology N2 - Based on niche theory, closely related and morphologically similar species are not predicted to coexist due to overlap in resource and habitat use. Local assemblages of bats often contain cryptic taxa, which co-occur despite notable similarities in morphology and ecology. We measured in two different habitat types on Madagascar levels of stable carbon and nitrogen isotopes in hair (n = 103) and faeces (n = 57) of cryptic Vespertilionidae taxa to indirectly examine whether fine-grained trophic niche differentiation explains their coexistence. In the dry deciduous forest (Kirindy), six sympatric species ranged over 6.0% in delta N-15, i.e. two trophic levels, and 4.2% in delta C-13 with a community mean of 11.3% in delta N-15 and - 21.0% in delta C-13. In the mesic forest (Antsahabe), three sympatric species ranged over one trophic level (delta N-15: 2.4%, delta C-13: 1.0%) with a community mean of 8.0% delta N-15 and - 21.7% in delta C-13. Multivariate analyses and residual permutation of Euclidian distances in delta C-13- delta N-15 bi-plots revealed in both communities distinct stable isotope signatures and species separation for the hair samples among coexisting Vespertilionidae. Intraspecific variation in faecal and hair stable isotopes did not indicate that seasonal migration might relax competition and thereby facilitate the local co-occurrence of sympatric taxa. KW - Chiroptera KW - community structure KW - congeneric species KW - ecological niches KW - migration KW - Neoromicia KW - Pipistrellus KW - Scotophilus KW - stable carbon KW - stable nitrogen Y1 - 2015 U6 - https://doi.org/10.1017/S0266467414000741 SN - 0266-4674 SN - 1469-7831 VL - 31 SP - 153 EP - 164 PB - Cambridge Univ. Press CY - New York ER -