Stable Isotopes Reveal the Dominant Species to Have the Widest Trophic Niche of Three Syntopic Microtus Voles

• Published in: Animals
• Main Authors: Linas Balčiauskas, Raminta Skipitytė, Andrius Garbaras, Vitalijus Stirkė, Laima Balčiauskienė, Vidmantas Remeikis
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2021
• Subjects: small herbivores; voles; niche width; orchards; berry plantations; meadows; Veterinary medicine; SF600-1100; Zoology; QL1-991; Common vole; Microtus arvalis
• Online Access: https://doi.org/10.3390/ani11061814; https://doaj.org/article/5bd98aee1f8e47daa5b515e736b0e133

Diets and trophic positions of co-occurring animals are fundamental issues in their ecology, and these issues in syntopic rodents have been studied insufficiently. Using carbon ( δ 13 C) and nitrogen ( δ 15 N) stable isotope ratios from hair samples, we analysed the trophic niches of common ( Microtus arvalis ), field ( M. agrestis ), and root ( M. oeconomus ) voles co-occurring in orchards, berry plantations, and nearby meadows (as control habitat to orchards and plantations). We tested if the niche of the dominant common vole was the widest, whether its width depended on the presence of other vole species, and whether there were intraspecific differences. Results suggest stability in the trophic niches of all three Microtus species, as season explained only 2% of the variance. The widest trophic niche was a characteristic of the dominant common vole, the range of δ 13 C values exceeding the other two species by 1.6, the range of δ 15 N values exceeding the other two species by 1.9, and the total area of niche exceeding that of the other voles by 2.3–3 times. In the meadows and apple orchards, co-occurring vole species were separated according to δ 13 C (highest values in the dominant common vole), but they maintained similar δ 15 N values. Results give new insights into the trophic ecology small herbivores, showing the impact of species co-occurrence.