DIET SELECTION OF 3 GRASSHOPPER SPECIES (ORTH, ACRIDIDAE), IN SPANISHPYRENEES

The faeces content of grasshoppers(Stenobothrus stigmaticus, Omocestus haemorrhoidalis and S.nigro maculatus) living free-range in three veg etal communities was analysed by microhistological techniques. The gra sshoppers' diet were compared with available vegetation and diet overl apping among three species was determined. Monocotyl plants constitute d from 92%-100% of diet. Festuca gr. rubra was the species most select ed by all grasshoppers in all areas we studied. Moreover, diet varies depending on plant communities. A high degree oi diet overlapping was found. Importance of grasshoppes' diet in pasture dynamics is discusse d.