Factors influencing grasshopper (Orthoptera: Acrididae) subfamily distribution along a vegetation gradient in northern bobwhite habitat

This research contributes to an effort to characterize arthropod community assemblages in Western Oklahoma grasslands that overlap with waning Northern Bobwhite populations.  Grasshoppers (Orthoptera: Acrididae) are significant arthropods in the grassland ecosystem.  They are important for returning nutrients to the soil through frass production and are important prey items for other insects, mammals, and birds including the Northern Bobwhite.  It has been observed that Acrididae subfamilies will partition habitat use based on dietary habits, with those that eat primarily grasses often in greater abundance in areas dominated by grass and those with a broader diet often in greater abundance in areas with a mix of grass and non-grass plants.  We initiated a habitat-based approach of grasshopper sampling on the Beaver River Wildlife Management Area (WMA) in Beaver, Oklahoma.  Using sweep net sampling, we attempted to characterize the community of Acrididae that exists along a vegetation gradient in the Beaver River WMA.  The vegetation types were characterized using a Daubenmire frame to estimate the proportion of cover of four different functional groups: grass, forb, litter, and bare ground.  Pearson correlation coefficients were calculated and determined significant (p < 0.05) relationships between the proportion of cover of functional groups and relative abundance of Melanoplinae and Gomphocerinae subfamilies.  A two factor factorial ANOVA with repeated measures was performed to determine significance between the relative abundance of Gomphocerinae and Melanoplinae grasshoppers in each vegetation type.  This research supports dietary-based habitat partitioning by Acrididae subfamilies.