Insektengemeinschaften (Insecta: Coleoptera, Heteroptera, Auchenorrhyncha) in Windwurfflächen am Latemar (Italien, Südtirol)

Insect communities (Insecta: Coleoptera, Heteroptera, Auchenorrhyncha) in windthrow areas at Mt. Latemar (Italy, South Tyrol). The storm “Vaia” caused large-scale windthrow in various parts of South Tyrol in October 2018. One of the most heavily affected areas was a montane and sub-alpine spruce stand known as “Latemarwald” in the vicinity of Lake Carezza/Karer See. Two years later, in the summer of 2020, the beetle, true bug and true hopper fauna was recorded in three habitat types: unaffected high forest stands, uncleared and cleared windthrow areas. Five sites of each habitat type were investigated with different methods, resulting in a total of 15 sampling sites. The aim of this survey was to compare the species composition of the three habitat types. The results should form the basis for further succession monitoring of the young windthrow areas. One hundred thirty-six beetle, 29 true bug and 24 true hopper taxa were recorded. Three beetle and one true bug species are first records for the fauna of South Tyrol. Only few endangered species were identified in each group. Both species numbers and abundance showed no significant difference in the high forest stands and the adjacent windthrow areas for all insect groups investigated. However, the overall species numbers were higher in windthrow areas, especially in uncleared sites from which both, the highest and the lowest species numbers, were recorded. A slightly but not significantly higher number of saproxylic beetle species, especially fresh wood dwellers, was recorded in uncleared sites. The proportion of open land species of true bugs and true hoppers and the number of ecological guilds increased in windthrow areas, the latter showing differences between the uncleared and cleared sites. In agreement with existing literature, we understand this as evidence that partial and mosaic-like clearance of windthrow areas is beneficial to biodiversity.