Can highland habitat type distributions replace mapping of harvestman species

In nature conservation, providing new, advanced knowledge of protected habitats and biota often requires extensive sampling, which contradicts the main goal of minimizing damage and disturbance. How to avoid this innate collision was the main concern in our study. Highland habitats are suitable for addressing this problem, since they are relatively species-poor and therefore easier to analyze. Invertebrate distributions are, to some extent, expected to vary congruently with habitat type (HT) distributions. However, studies of such effects are scarce. In this study we researched harvestmen (Opiliones) in highland habitats above 1,800 m in the Kamnik-Savinja Alps, a Natura 2000 area in Slovenia. The question was whether mapping of HT distributions could predict the presence of the harvestman species and replace their laborious mapping. For this purpose, we studied relationships between the HT distributions and the harvestman species distributions with respect to environmental conditions. Chao2 and Jackknife1 were found to provide the best estimates of total species diversity. In assessing the species richness, the incidence-based approach was applied. No indicator harvestman species for the HTs, and no statistical difference was found in the harvestman community structure of three most frequently inhabited HTs. Most HTs and harvestman species responded gradually and in parallel to the changing environmental conditions along the altitudinal gradient, revealing covariation of their distributions. Hence, knowledge of highland HT distributions cannot replace the mapping of harvestmen.