During the inventories conducted at Snježnik, Guslica, Lazac, Šegine, Risnjak and Hrvatsko, a total of 89 species of butterflies were recorded. A total of 11 endangered species of butterflies were found, 8 in Kupa valley. The Kupa valley and the western slopes of Dimovac Hill above Hrvatsko are important sites for butterflies with 69 species recorded. Near Hrvatsko there are important wetland meadows with threatened species: the marsh fritillary (Euphydryas aurinia), in riverine bushes and trees with the purple emperor (Ampatura iris) and poplar admiral (Limenitis populi); the boundary between forest and meadow near the Kupa features the woodland white (Leptidea morsei), while mostly abandoned small dry grasslands on the slopes of Dimovac have the checkered blue (Scolintatides orion), Nickerl´s fritallary (Mellicta aurelia), green-underside blue (Glauscopsyche elexis) and woodland ringlet (Erebia medusa).

Four species of threatened butterflies were found on the Šegine grasslands.

Through a butterfly inventory on each meadow, baseline data for future monitoring will be established, thus enabling control of future management activities for semi-natural grasslands and conservation of their biodiversity.