The Effect of Floristic Composition on Bird Communities in a Set of Four Grassland Reconstruction Types

Abstract

With most native prairie now lost, focus has turned to reconstructing grasslands with the aim of replicating ecosystem function for grassland fauna and flora. We report the results of a seven-year study (2008–2014) on the use of four floristically different prairie reconstructions by grassland birds. The study was conducted near Austin, Minnesota on a 64.75-ha (160-acre) Wildlife Management Area. Prairie reconstruction was implemented in 2005 on land previously used for row crops, and the study site consisted of eight identically sized (4.5 hectare), side-by-side of replicates of four distinct planting mixes. We used fixed-point transect surveys to document differences in the number of species and individuals of grassland birds between plot types. We found differences in the abundance of individuals and diversity of bird species between plot types, with fewer bird species and individuals present in lower plant-diversity plot types compared to higher plant-diversity plots. Eighteen species of grassland birds were recorded on the site, with none exclusively restricted to any plot type. Grassland obligate bird species, including Sturnella magna (Eastern Meadowlark), Dolichonyx oryzivorus (Bobolink), Ammodramus savannarum (Grasshopper Sparrow), Ammodramus henslowii (Henslow’s Sparrow), and Passerculus sandwichensis (Savannah Sparrow), were documented using low floristic diversity, cool-season grass plots. Other species, such as Spiza americana (Dickcissel), Melospiza melodia (Song Sparrow) and Spinus tristis (American Goldfinch), showed preferences for high diversity, forb dominated plots. Our results indicate that planting a mosaic of restoration mixes may be the most successful at attracting and retaining the highest diversity of bird species.