The Nightjar (Caprimulgus europaeus) has experienced a reduction in range and numbers over much of Europe and is, as such, a species of conservation concern. We performed a survey of singing males and a research of habitat selection in the western part of IBA Snežnik – Pivka, which is the second most important area for the Nightjar in Slovenia. We selected 16 habitat parameters, based on the Nightjar’s ecology. The parameters were different land uses, types of forest and topographic characteristics. We carried out a field survey of meadows and categorized them into three classes based on the management type: intensive, extensive and pastures. We performed the logistic regression model using the program RStudio. We surveyed the Nightjars by the point-count method using the playback of the male song. We registered 129 Nightjars at 125 survey points. The estimated crude density was 2.08 singing males per km2; the highest estimated density was 4.24 singing males per km2. The estimated population size was 432 singing males (range: 389 – 510), which constitutes about a third of the entire population in Slovenia. The logit model predicts a higher probability of the Nightjar occurrence in areas covered by overgrowing grasslands with trees, coniferous forests, extensive meadows and a long forest edge. Arable land and intensive meadows were found unsuitable for the Nightjar.
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