Drobne gryzonie ubogich i żyznych siedlisk leśnych Roztoczańskiego Parku Narodowego

Small mammals, particularly rodents, play a crucial role in forest ecosystems as primary prey for predators, consumers of plants, fungi, and invertebrates, and as vectors for seed and spore dispersal. According to the habitat heterogeneity hypothesis, greater habitat diversity typically leads to increased species richness. However, the mechanisms linking forest productivity and small mammal community structure remain insufficiently understood, especially in protected areas where biodiversity conservation is a priority. This study aimed to assess the species composition and population dynamics of small rodents in two contrasting forest habitats - nutrient-poor pine forests and nutrient-rich mixed deciduous forests in Roztocze National Park, Poland. Rodent trapping was conducted in 2024 and 2025 using the capture-markrecapture (CMR) method on eight permanent plots (four per habitat type), each 0.25 ha, during early summer and autumn. Results revealed a stark contrast between habitats. In mixed forests, the yellow-necked mouse (Apodemus flavicollis) dominated, with densities reaching up to 78 ind./ha in 2025, while the bank vole (Myodes glareolus) was dominant but much less abundant in pine forests (maximum 0.75 ind./ha). Seasonal and interannual fluctuations were observed, with a significant increase in mouse numbers following a mast year for oaks. Analyses of reproductive rates and body mass revealed that males were heavier than females; however, no significant seasonal or annual differences in body mass were found. The findings highlight that habitat productivity has a strong influence on both the abundance and species composition of small rodents. Fertile mixed forests support higher densities and diversity, providing richer food resources for predators, while poor pine forests offer limited resources and lower rodent densities.