Stable isotopes reveal the dominant species to have the widest trophic niche of three syntopic Microtus voles

• Published in: Animals
• Main Authors: Balčiauskas, Linas, Skipitytė, Raminta, Garbaras, Andrius, Stirkė, Vitalijus, Balčiauskienė, Laima, Remeikis, Vidmantas
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2021
• Subjects: small herbivores; voles; niche width; orchards; berry plantations; meadows; Lithuania; Common vole; Microtus arvalis
• Online Access: https://vb.ftmc.lt/FTMC:ELABAPDB100146604&prefLang=en_US

Diets and the trophic positions of animals are fundamental issues in their ecology. We analysed the isotopic niches (as a proxy for trophic niches) of common (Microtus arvalis), field (M. agrestis), and root (M. oeconomus) voles co-occurring in orchards, berry plantations, and nearby meadows using isotopic (δ15N and δ13C) compositions from hair samples. We tested if the niche of the dominant common vole was widest, whether its width was related to the presence of other Microtus species, and whether there were intraspecific differences in average δ13C and δ15N stable isotope values. The obtained results showed relative stability in the trophic niche across the vegetative period. The isotopic niche of the common vole was the widest, exceeding the other two Microtus species by 1.6–3 times. Co-occurring vole species were separated according to δ13C (i.e., used different plants as main food), but they maintained similarity according to δ15N distribution. The effect of animal age and gender on the width of the trophic niche was strongest in root vole, which is a species that has spread across the country in the last 70 years. These results give new insights into the trophic ecology small herbivores, showing the impact of species co-occurrence.