Document


Title

Survival of grasshopper sparrows (Ammodramus savannarum) during two important life stages in grassland managed with fire and grazing
Document Type: Thesis
Author(s): Torre J. Hovick
Publication Year: 2010

Cataloging Information

Keyword(s):
  • Ammodramus savannarum
  • cattle
  • daily survival rate
  • fire
  • grasshopper sparrow
  • grassland
  • grazing
  • Great Basin
  • heterogeneity
  • Iowa
  • nest predators
  • nest success
  • patch burn grazing
  • tallgrass prairie
Region(s):
Record Maintained By:
Record Last Modified: November 12, 2015
FRAMES Record Number: 18095

Description

Patch-burn grazing (PBG) is a management practice intended to benefit grassland-dependent wildlife. This practice relies on a fire-grazing interaction to create a habitat mosaic that is heterogeneous in terms of structure and composition, mimicking historic conditions. To assess effects of this, we studied nesting and postfledging survival of Grasshopper Sparrows (Ammodramus savannarum), in pastures under two treatments: PBG (grazed, 1/3 burned annually) or graze-and-burned (grazed, entire pasture burned every third year).The study was conducted in Ringgold County, Iowa, on public and private lands. We found 332 Grasshopper Sparrow nests in 2008 and 2009. In 2009 we attached 50 transmitters to randomly selected nestlings one day prior to fledging. We found that nests in graze-only pastures had a daily survival rate (DSR) of 0.90 (SEy 0.01), and nests found in PBG pastures had a DSR of 0.92 (SEy 0.007). Postfledging survival across treatments was low, with 10 chicks surviving >14 days. Mortality rates were highest within three days of fledging (>48%). We would caution against assessing management with nest survival alone due to high rates of mortality during the postfledging stage.

Online Link(s):
Citation:
Hovick, Torre. J. 2010. Survival of grasshopper sparrows (Ammodramus savannarum) during two important life stages in grassland managed with fire and grazing. Master of Science. Ames, IA: Iowa State University. 79 p.