Impact of wild ungulate grazing on Orthoptera abundance and diversity in subalpine grasslands
Article first published online: 28 NOV 2011
© 2011 The Authors. Insect Conservation and Diversity © 2011 The Royal Entomological Society
Insect Conservation and Diversity
Volume 5, Issue 6, pages 444–452, November 2012
How to Cite
SPALINGER, L. C., HAYNES, A. G., SCHÜTZ, M. and RISCH, A. C. (2012), Impact of wild ungulate grazing on Orthoptera abundance and diversity in subalpine grasslands. Insect Conservation and Diversity, 5: 444–452. doi: 10.1111/j.1752-4598.2011.00180.x
- Issue published online: 20 NOV 2012
- Article first published online: 28 NOV 2011
- Accepted 31 October 2011 First published online 28 November 2011 Editor: Alan Stewart Associate editor: Nick Littlewood
- habitat structure;
- red deer;
- vegetation composition;
- vegetation height
Abstract. 1. Grasslands cover approximately 40% of the Earth’s terrestrial landscape, supporting large communities of vertebrate and invertebrate herbivores. Orthoptera play an important role, consuming relatively large amounts of biomass. Their occurrence can be strongly affected by habitat diversity and structure, which can be shaped by large herbivores. Several studies have focused on the impact of livestock on Orthoptera communities, but little is known about how wild ungulates influence the abundance and diversity of these insects in grassland ecosystems.
2. We studied Orthoptera abundance and diversity in subalpine grasslands in the Swiss Alps, where grazing by red deer and chamois has created a mosaic of short- and tall-grass patches. Data on vegetation structure, habitat diversity and plant nitrogen (N) content allowed us to consider how these parameters affected the occurrence of Orthoptera at our study sites.
3. We found a total of nine Orthoptera species with an average density of 2.6 individuals m−2. Neither Orthoptera abundance nor diversity differed between short- and tall-grass patches created by large ungulates. Both Orthoptera abundance and diversity were, however, positively influenced by increasing vegetation height, but negatively by increasing habitat diversity within patches. Increasing plant N content promoted a more even spread of species within the insect assemblage on short- but not on tall-grass patches.
4. Large-scale habitat alteration by wild ungulates had no direct effect on the abundance and diversity of Orthoptera. However, we observed that they indirectly affected Orthoptera abundance and diversity by altering plant N content and the structure of the habitat at small scales.