Sampling method assessment and quantification of temporal shifts in densities of grasshopper species (Orthoptera: Acrididae) between winter wheat, Triticum aestivum, and adjacent rangeland

In this study, we determined that 2 sampling methods (D-Vac and sweep net) taken al weekly intervals could be used to sample grasshopper species across 2 adjacent habitats of winter wheat and rangeland. We also quantified temporal density estimate shifts between winter wheat, Triticum aestivum L., and rangeland by migratory grasshoppers, Melanoplus sanguinipes (F.), twostriped grasshopper, M. bivittatus (Say), and Packard grasshopper, M. packardii Scudder, all 3 species coinhabit these areas. Specifically, at 4 study sites with the highest grasshopper densities there were significant seasonal shifts in density estimates of these species between winter wheat and rangeland suggesting that these species dispersed between habitats. At a 5th site, sweep net sampling detected a shift in density estimates between habitats by M. sanguinipes and D-Vac sampling at this site suggested there was a similar trend. At 4 study sites such shifts in density estimates did not occur suggesting that no dispersal occurred or it was not detectable at these sites using our sampling methods. In all but 1 case the density of these species, were lower than those where density estimate shifts occurred.