Document


Title

Grassland bird response to a fire-grazing interaction in a fragmented landscape
Document Type: Thesis
Author(s): Finn C. Pillsbury
Publication Year: 2011

Cataloging Information

Keyword(s):
  • Ammodramus henslowii
  • Ammodramus savannarum
  • fire
  • fragmented landscapes
  • grasshopper sparrow
  • grassland
  • grassland birds
  • grazing
  • Great Plains
  • Henslow's sparrow
  • heterogeneity
  • Iowa
  • Missouri
  • patch burn grazing
  • tallgrass prairie
Region(s):
Record Maintained By:
Record Last Modified: November 12, 2015
FRAMES Record Number: 18101

Description

Grassland birds have experienced widespread population declines throughout the North American tallgrass prairie region, largely as a result of habitat loss and the homogenization of remaining fragments. Recent work in relatively extensive grasslands has demonstrated that mimicking historic disturbance patterns using a fire-grazing interaction can increase the abundance and diversity of grassland birds by providing more habitat heterogeneity. We examined the efficacy of management that restores a fire-grazing interaction for promoting avian diversity in a fragmented landscape. We quantified the relative abundance of obligate and facultative grassland bird species along transects in 13 experimental research pastures in the Grand River Grasslands of Iowa and Missouri (USA), divided among three treatments: 1) spatially discrete fires and free access by cattle ("patch-burn grazing"), 2) free access by cattle and a single complete burn ("grazed-and-burned"), and 3) a single complete burn with no cattle ("burned-only"). We expected that patch-burn grazing would produce a bird community intermediate between those of the grazed-and-burned and burned-only treatments, because it would provide habitat for species associated with both. However, an analysis of similarity (ANOSIM) showed that community structure on pastures managed using patch-burn grazing instead diverged significantly from both of the other treatments. Differences in community structure were most highly correlated with visual obstruction and wooded edge density in the landscape, suggesting bird communities are differentiated not only by their structural habitat requirements, but also by the varying degrees of sensitivity to landscape fragmentation of their component species.

Online Link(s):
Citation:
Pillsbury, Finn C. 2011. Grassland bird response to a fire-grazing interaction in a fragmented landscape. Master of Science. Ames, IA: Iowa State University. 114 p.