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Cities offer new habitats not only for humans but also for a range of species,particularly rodents.For example there are many different types of soils,illuminations,temperatures,humidities and noise levels.Modification of the natural environment leads to fundamental changes in biodiversity and populations of particular species.Changes in urban fauna can be traced in three ways: monitoring changes in flora and fauna over a long period of time (historical changes) ; comparing a series of urban localities of differing sizes and environmental characteristics; analyzing the trends from the outer peri-urban areas to the highly urbanized downtown areas.Together these approaches enable us to identify common patterns that may occur in the dynamics of the rodent fauna and their relationship with the degree of urbanization.To reveal trends in the abundance of rodent species from the peripheral to the downtown areas we divided the territory into a number of zones according to the proportion of vacant and built areas.This trend can be characterized by the A (arbor) -E (eremus) –gradient.It shows the ratio of the species with different propensities for commensalism and allows us to estimate the extent of transformation of the urban environment in a particular location.Each city has its own trends in A-E-gradients and they can help us to analyze significant factors which have the greatest influence on rodent fauna distribution and abundance.Understanding these influences can help us to plan to manage them in the future.