The diploma thesis focuses on abundance assessment of birds living in urban areas. We detected bird diversity and abundance during the breeding season of 2019, situated in five locations in Žilina town. The presented data are discussed in order of the breeding birds communities of the urban environments from different parts of Slovakia. Urbanisation is represented by the ecological forcing functions created by the growth of cities and associated human activities. Birds seem to be suitable model organisms for determining the interactions between urbanisation and biota. Strong urbanisation exerts a negative effect on bird communities in general. Urban development and increasing population concentrations put natural city environments under great pressure. Negative trends in city structure and spatial planning decrease the natural environment and thus contribute to the negative impacts of climate change. The concept of green infrastructure is aimed – similarly as the territorial systems of ecological stability - at the gradual transition from the black-and-white division of the landscape to the protected and unprotected parts to an all-area differentiated system of land use with different degree of ecological stability. Green infrastructure is a well-established concept in European strategies and policies.