Landscape and farm environmental structure determinants of small mammal assemblages in agroecosystems of central Argentina

Abstract

Natural processes and patterns are altered by human activity at different spatial and temporal scales, affecting species assemblages and population traits, modifying mechanisms or regulating dynamics at different scales. However, little is known about the influence of landscape structure on small mammal assemblages and populations on farms. Thus, in this work, we aimed to study the effect of landscape and environmental characteristics at the farm scale on the assemblage and populations of native and introduced small mammals in pig and dairy farms located in Buenos Aires province, Argentina. Our results showed that farms in contexts of higher environmental diversity at the landscape scale have higher species richness. Our results also showed that variations in assemblage composition were associated with the quantity of water body surfaces, cattle food, small mammal refugia, and impervious surfaces at the farm scale—and with woodland, grassland, and natural vegetation cover at the landscape scale. The abundance of commensal murids was higher on farms near towns, with higher vegetation cover at the farm scale and/or in landscape contexts with fewer crops. The abundance of Akodon azarae was higher on farms with a lower amount of cattle food at the farm scale and crop patches in the landscape. The abundance of Didelphis albiventris was higher during spring on farms with a low proportion of bare ground, while that of Lutreolina crassicaudata was higher on farms with high vegetation cover and a lower number of water body surfaces. These results show the relevance of multiscale determinants in the development of ecologically based management strategies to control pest small mammals.