The impact of altitude on the population dynamics of the common vole

This study examines how altitude affects the population dynamics of the common vole (Microtus arvalis) in the Martakert region of Nagorno-Karabakh, using a 25-year dataset (1999–2023) from lowland (low-altitude) and foothill (high-altitude) zones. We hypothesised that low-altitude populations show less seasonal variability due to milder climates with shorter winters. Data on vole captures, adjusted for trapping effort (surveys × active traps), were analysed with generalised linear mixed models (GLMMs) with a Gaussian distribution, incorporating region × season interactions, linear year trends, and random site effects. Results showed significantly higher mean vole abundances at low-altitude sites (11.9 individuals/100 trap-days) than at high-altitude sites (8.0 individuals/100 trap-days). Seasonal dynamics showed pronounced declines from spring to winter, but the interaction term indicated attenuated winter crashes at low altitudes. Model validation confirmed a good fit, with no residual patterns. These findings highlight altitude-driven differences in vole dynamics, informing pest management and ecological monitoring in agroecosystems amid climate change.