This paper addresses a current issue regarding the increasing problem of a decreasing cattle population in the Polish Carpathians. The problem exacerbated after 1990, as a result of changes in prices of the means of production and agricultural products. It intensified even further after Poland joined the EU. The decrease in cattle population is observed in all districts in the Carpathians. This article includes a diagnosis of four such districts: two with the highest decrease (Łańcut: -67.0% and Sucha: -52.6%) and two with the smallest decrease in cattle population (Bieszczdy: -8.1% and Wadowice: -11.5%). Expert assessments were used to this end. The article includes a definition and analysis of the deanimalisation process and an indication of the consequences of this process in agriculture, in the local environment and in the broadly understood ecological context. It follows from the research that favourable natural conditions, good for breeding ruminants, largely determine high cattle density but, at the same time, these conditions do not impact the decrease in the cattle population to such an extent. The decrease is related to the low concentration of herds, generational changes and the disappearance of local dairy markets. As a result of progressing deanimalisation, abandoned meadows and pastures, as well as part of arable lands, are being permanently lost. Instead, these lands become overgrown with invasive plant species and shrubbery.