Our new paper is published about the effects of steppe mice on the vegetation of agroecosystems

Our new paper by Laura Godó et al. has recently been published in Agriculture, Ecosystems and Environment about the effect of mound-building and caching activities of the steppe mouse.

Reference

Godó, L., Valkó, O., Borza, S., Ferencz, A., Kiss, R., Lukács, K., Deák, B. (2024) Effects of mound building and caching by steppe mouse (Mus spicilegus Petényi) on the vegetation in agroecosystems. Agriculture, Ecosystems and Environment 379: 109359. https://doi.org/10.1016/j.agee.2024.109359.

The paper is open access and can be downloaded from here.

To analyse the complex effects of caching rodents on agroecosystems, we selected the steppe mouse (Mus spicilegus Petényi, 1882), a small outdoor mouse, as a model species. It is a common herbivorous rodent inhabiting grasslands and agroecosystems from eastern Austria to western Russia. Its most well-known and spectacular habitat transformation effect is mound building: in autumn, a group of mice gather and build a mound above their burrow that provides protection against harsh environmental conditions and weather elements during the winter period. The mound consists of a thick layer of piled up inflorescences, fruits, and spikes covered by shallow bare soil layer. Therefore, these mounds are very interesting objects for vegetation dynamics: they contain huge amount of seeds, and they provide small distinct patches for plant establishment.

Our findings suggest that small-scale disturbances, like mound-building by the steppe mouse, contribute to maintaining plant diversity in otherwise uniform agroecosystems. The mounds provide low-competition sites with unique resources, creating small vegetation patches that differ from surrounding areas. The steppe mouse may act as a "facultative engineer" species, influencing vegetation based on habitat type. However, the mounds are often short-lived due to agricultural activity, leading to a constantly shifting pattern of mound sites, which temporarily facilitate plant establishment.

Seed analysis of the mouse's caches showed a preference for a few weed species, but only a few of these appeared in the vegetation on mounds. This finding suggests that while mounds provide good conditions for cached weeds, they don't result in significant weed growth, which may help change farmers' perceptions of these rodents as pests. As a common species adapted to disturbed habitats and expanding across Europe due to milder winters, the steppe mouse may increasingly affect agroecosystem structure and function in the region.

Abstract

Several rodent species are considered ecosystem engineers. They exert profound changes in agroecosystems by disturbing the soil during their activities. The steppe mouse (Mus spicilegus) inhabits various agroecosystems and constructs conspicuous mounds for overwintering using piled up plant material and soil. These mounds are widespread in many agroecosystems and may significantly affect the vegetation. In our study, we evaluated the effect of mound building activity of the steppe mouse on the vegetation of agroecosystems in Hungary. We sampled the cache content of 90 mounds in total located in old fields, alfalfa fields, and annual crop fields, and surveyed the aboveground vegetation of the mounds and their surrounding undisturbed matrix in 39 paired plots. Mice cached large amounts of seeds belonging mostly to weeds. In total we found 50,413 germinable seeds of 30 species in the cache content samples. However, the mound vegetation and the cache shared only a few species, suggesting that seeds cached by the mice do not contribute to the regenerating vegetation on the mounds. Soil disturbance by mice created distinct vegetation patches with species composition and structure different from the neighbouring undisturbed matrix. Early secondary successional vegetation patches on mounds introduced small-scale heterogeneity into the homogenous agricultural landscape, increased plant diversity and provided distinct flower resources for pollinators. The detected differences in the aboveground vegetation between the mound and the matrix in the studied habitats suggest that the steppe mouse acts as a facultative engineer species in agroecosystems.