Effect of Bird Predation on Grasshopper and Plant Communties
Experiment Id

This experiment was set up in the same macroplots at Field B E004 that were used in E060. Pairs of 9 m x 9 m plots were demarcated. One plot in each pair was randomly assigned to exclude birds (BEX) and the other to allow birds to forage for grasshoppers in the vegetation (BAL). A frame was built around BEX plots with wooden posts at each corner and heavy aluminum wire stretched between posts 1m above the ground. Bird netting (2.5 cm mesh) was then stretched over this framework and attached to the ground with numerous wire stakes. In 1989, these plots were set up 15 July, but were set up 15 May in 1990 to examine the effects of predation in the early summer. Between 15-25 August, netting was removed and grasshoppers were sampled within both BEX and BAL plots and stored in 70% ethanol for later identification to species or genus, counting and weighing. Grasshoppers were sampled by two people with butterfly nets. After the grasshoppers were sampled, the vegetation was sampled. Within each 9 m x 9 m plot, three 0.1 m x 3 m strips were clipped, sorted to species, dried and weighed. In 1990, the exclosures were set up 15 May, but all vegetation and grasshopper sampling was similar to that in 1989. For a list of treatments, see the treatment layouts in file trmte61.