Lack of detectable genetic isolation in the cyclic rodent Microtus arvalis despite large landscape fragmentation owing to transportation infrastructures

Abstract

Although roads are widely seen as dispersal barriers, their genetic consequences for animals that experience large fluctuations in population density are poorly documented. We developed a spatially paired experimental design to assess the genetic impacts of roads on cyclic voles (Microtus arvalis) during a high-density phase in North-Western Spain. We compared genetic patterns from 15 paired plots bisected by three different barrier types, using linear mixed models and computing effect sizes to assess the importance of each type, and the influence of road features like width or the age of the infrastructure. Evidence of effects by roads on genetic diversity and differentiation were lacking. We speculate that the recurrent (each 3–5 generations) episodes of massive dispersal associated with population density peaks can homogenize populations and mitigate the possible genetic impact of landscape fragmentation by roads. This study highlights the importance of developing spatially replicated experimental designs that allow us to consider the large natural spatial variation in genetic parameters. More generally, these results contribute to our understanding of the not well explored effects of habitat fragmentation on dispersal in species showing “boom-bust” dynamics.

The genetic structure and connectivity in two sympatric rodent species with different life histories are similarly affected by land use disturbances

“…Habitat fragmentation did not produce a detectable loss of genetic variation in the two species. Levels of diversity in different populations are comparable to those reported for other rodent species (Czarnomska et al 2018;Dominguez et al 2021;Gerlach and Musolf 2000;Martin Cerezo et al 2020). When the global genetic divergence between populations was analyzed, the wood mouse showed much weaker population structure than the bank vole.…”

Identifying Ecological Security Patterns Considering the Stability of Ecological Sources in Ecologically Fragile Areas

“…Available habitats, such as steppingstones, can be placed along long key corridors to reduce spatial distance and enhance the ecosystem's flexibility. Furthermore, the impact of road construction on ecological network connectivity has been a focal point in recent research, as roads may obstruct species migration or alter migration routes [72]. The distance from railways, expressways, and main roads was found to contribute significantly to the high resistance values in this study.…”

A Systematic Review and Meta-Analysis of the Inhibitory Effects of Plant-Derived Sterilants on Rodent Population Abundance

“…In small environments, such as shops, airports, and warehouses, it may be desirable to kill all rodents. However, when considering the entire ecosystem, making rodents sterile can better achieve the purpose of controlling their population abundance [ 49 ]. Throughout 2000 years of human practice of rodent eradication, it has appeared that, even when all eradication means are pursued, it is impossible to eliminate all rodents in a certain environment [ 50 , 51 ].…”