PBG05 Response of bird abundance to the Patch-Burn Grazing experiment at Konza Prairie

‘PBG’ datasets are associated with a long-term, large-scale study that is addressing the effects of fire-grazing interactions in the context of a Patch-Burn Grazing management system designed to promote grassland heterogeneity. Effects of patch-burn grazing management on plant and animal diversity and the nature and variety of wildlife habitat are being assessed in two replicate management units, each consisting of three pastures (watersheds) designated C03A/C03B/C03C and C3SA/C3SB/C3SC. In each patch-burn grazing unit, one watershed is burned and two that are left unburned in a given year. The burning treatments are rotated annually so that each pasture is burned every third year. Each patch-burn grazing unit is paired with an annually-burned pasture for comparison with traditional grazing systems (C01A and C1SB). All grazing units are stocked with cow/calf pairs from approximately 1 May until 1 Oct at a stocking density equal to 3.2 ha per cow/calf. To examine the impact of patch burning and grazing in all 8 units, we monitor changes in plant species composition, residual biomass, grassland bird populations, insect populations, small mammal populations, soil nutrients, and stream water quality1 (1C3SA/C3SB/C3SC unit only). The KSU Department of Animal Science monitors cattle performance, including weight gain and body condition to assess the economic feasibility of using patch-burn management on a widespread basis. This data set focuses on variation in avian abundance, diversity, and nesting activity between patch-burned and uniformly-burned pastures at Konza Prairie Biological Station. Three watershed units (C3A, C3B, C3C) constitute 'patches' that are alternately burned in a 3-year rotation within a single, fenced pasture (i.e., patch-burn grazing). Two additional watersheds serve as controls: a grazed, annually/uniformly-burned watershed (C1A) and an ungrazed, annually/uniformly-burned watershed (1D). Eight, 300-m line transects were established in each watershed from which observers record the numbers of individuals per bird species and the perpendicular distance of individual birds from each transect. Three visits are made to each watershed between the last week in May through the end of June, where two 'core' transects per watershed are sampled each visit. Six additional transects per watershed are sampled, but only once in a given year (two peripheral transects are sampled per watershed, per visit). The survey data will allow estimates of relative abundance, absolute density (determined from distance sampling), and species composition and diversity among the patch-burned and control watersheds. Vegetation structure is sampled along survey transects to characterize management-specific variation in physical attributes of avian habitat. Nest data are collected through systematic searches of nests throughout watersheds or from inclusion of nests found haphazardly by observers. Nest data are being analyzed for variation in daily nest survival and levels of brood parasitism of various species among the watershed units.