To this day, there has been very little research regarding the exploration of habitat characteristics of capercaillie leks in Slovenia. This knowledge is crucial for discerning and exercising measures for preserving and increasing species abundance. The aim of this study is to determine the recent activity of 20 known capercaillie leks on Uršlja Gora and its surroundings in comparison with past surveys (Adamič, 1986; Čas, 2000) and to record potential new ones. We also wanted to establish any differences in habitat characteristics between active and abandoned capercaillie leks. We conducted our research with methodical listening of singing males early in the morning and taking note of their presence at the time of their mating season between 1. 4. and 20. 5. in 2019 and 2020. Survey of habitat characteristics was implemented in three active and three abandoned leks. The number of active leks has significantly decreased compared to the surveys in 1986 and 2000 (only 30 % of known leks has remained active). We documented approximately 3 times fewer active males, three more inactive males and 2,7 times less females than in 2000. From that we conclude that the species is endangered in the study area and could disappear in the next few decades if their numbers continue to decrease. The percentage of abandoned leks was higher in forests with lower altitude (below 1200 m). We did not document any new leks, but we discovered that the centres of active leks have shifted compared to the last survey. We also discovered differences in habitat characteristics between both types of leks. Compared to abandoned leks, active leks experienced higher cover of herbaceuous layer (85 %, 24 % being berries), higher number of anthills, low canopy cover (40–60 %), higher ground level visibility and higher percentage of old conifer stands. Ground level visibility and percentage of different tree species did not considerably affect leks activity.
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