A meta-analysis of lesser prairie-chicken nesting and brood-rearing habitats: implications for habitat management

Abstract

The distribution and range of lesser prairie-chicken ( Tympanuchus pallidicinctus ) has been reduced by >90% since European settlement of the Great Plains of North America. Currently, lesser prairie-chickens occupy 3 general vegetation communities: sand sagebrush ( Artemisia filifolia ), sand shinnery oak ( Quercus havardii ), and mixed-grass prairies juxtaposed with Conservation Reserve Program grasslands. As a candidate for protection under the Endangered Species Act, there is a need for a synthesis that characterizes habitat structure rangewide. Thus, we conducted a meta-analysis of vegetation characteristics at nest sites and brood habitats to determine whether there was an overall effect (Hedges' d ) of habitat selection and to estimate average (95% CI) habitat characteristics at use sites. We estimated effect sizes (d i ) from the difference between use (nests and brood sites) and random sampling sites for each study ( n = 14), and derived an overall effect size (d ++ ). There was a general effect for habitat selection as evidenced by low levels of variation in effect sizes across studies and regions. There was a small to medium effect (d ++ ) = 0.20-0.82) of selection for greater vertical structure (visual obstruction) by nesting females in both vegetation communities, and selection against bare ground (d ++ = 0.20-0.58). Females with broods exhibited less selectivity for habitat components except for vertical structure. The variation of d ++ was greater during nesting than brooding periods, signifying a seasonal shift in habitat use, and perhaps a greater range of tolerance for brood-rearing habitat. The overall estimates of vegetation cover were consistent with those provided in management guidelines for the species.