North American grasslands once covered vast areas of the continent. However, at present most have been altered or have ceased to exist as functioning prairie ecosystems with their full compliment of plant and animal species. Of all the North American grasslands, tall- and mid-grass prairies are among the most severely altered. Over the past 25 years, data from the U.S. Geological Survey's North American Breeding Bird Survey indicate that almost 70% of the 29 grassland bird species adequately surveyed showed evidence of declining populations (Knopf 1994; U.S. Department of Interior 1996; Sauer et al. 2000).

Grassland birds were initially selected for monitoring as indicators of overall prairie ecosystem health. Grassland bird inventories were conducted in the parks in 1998 and 1999 as a preliminary step toward developing long-term monitoring. Dr. Powell concluded that grassland habitat within most of the program parks was insufficient to support large numbers of grassland birds. She recommended implementing bird community monitoring at Agate Fossil Beds NM, and Tallgrass Prairie NP, the only parks where grassland bird species represented a relatively high proportion of bird species present.

Monitoring questions and approach

1. What is the current status in grassland bird populations? What are the long-term abundance trends?

   • Annual censuses conducted during the breeding season using variable circular plot counts to track the location, abundance, and trends of bird species through time.

2. What is the current condition of prairie habitat, and how is it changing through time?

   • Plant community composition and structure data are collected in conjunction with annual breeding bird surveys so that monitoring results can be tracked over time and correlated with habitat characteristics.

3. Are changes in population status or habitat quality correlated with management regimes?

   • Record management actions for correlation with monitoring results.

Protocol

• Protocol: Peitz, D.G, S.G. Fancy, L.P. Thomas and B.D. Witcher. In preparation. Bird monitoring protocol for Agate Fossil Beds National Monument, Nebraska and Tallgrass Prairie National Preserve, Kansas. Prairie Cluster Prototype LTEM Program, National Park Service, Republic, MO.

Reports

• Go to the Reports page.

References

• Knopf, F.L. 1994. Avian assemblages on altered grasslands. Studies in Avian Biology 15: 247-257.

• Sauer, J.R., J.E. Hines, I. Thomas, J. Fallon, and G. Gough. 2000. The North American breeding bird survey, results and analysis 1966 – 1999. Version 98.1, USGS Patuxent Wildlife Research Center, Laurel, MD. Available from: http://www.mbr-pwrc.usgs.gov/bbs/bbs.html