Risch Anita Christina
Impact of wild ungulate grazing on Othoptera abundance and diversity in subalpine grasslands.
Project Number: CH-4657
Grasslands cover almost 41% of the Earth’s terrestrial landscape and support large communities of vertebrate and invertebrate herbivores. Orthoptera play an important role within grassland ecosystems as they can consume large amounts of biomass. The occurrence of Orthoptera is strongly affected by habitat diversity and vegetation structure, which in turn can be shaped by large herbivores. Indeed, several studies focused on the impact of livestock on Orthoptera communities, but little is known about the impact of wild ungulates on abundance and diversity of Orthoptera in grasslands.
In the Swiss National Park (SNP) red deer (Cervus elaphus L.) and chamois (Rupicapra rupicapra L.) strongly influence the vegetation structure of subalpine grasslands and create a distinct vegetation pattern: short-grass (SG) is found where wild ungulates graze intensively, tall-grass (TG) in areas subject to less grazing. Our main goal was to determine how vegetation type (SG or TG), as well as vegetation structure and habitat diversity affected Orthoptera abundance and species diversity. In addition, we assessed difference in Orthoptera species composition among different grasslands in the SNP.
In total we found nine Orthoptera species, and caught 0.5 individuals per square meter on average. Our results showed that Orthoptera abundance and diversity were not influenced by vegetation type, i.e., no difference was found between Orthoptera numbers in SG and TG. However, Orthoptera abundance was positively influenced when the vegetation was taller and composed of more grasses, but negatively when habitat diversity increased. Orthoptera species diversity also increased with increasing vegetation height, and decreased with increasing habitat diversity. Orthoptera species composition at the different locations differed considerably and could be explained by vegetation structure, habitat diversity, altitude and distance and is roughly the same as some eighty years ago.
Spalinger, Lena. 2011. Impact of wild ungulate grazing on Othoptera abundance and diversity in subalpine grasslands. Master thesis ETH Zurich.PDF
Last update: 7/18/17
Source of data: ProClim- Research InfoSystem (1993-2020)
Update the data of project: CH-4657