Habitat and Population Evaluation Team
Midwest Region


Tree Removal and Grassland Birds

Waterfowl Production Areas (WPA's) in the prairie pothole region of Minnesota frequently have a significant woody component that is incompatible with the purposes of conserving habitat for grassland birds. Woody vegetation not only uses up space that could otherwise be grass cover, but many grassland bird species need grass in patches many times larger than their territory size or they will simply refuse to use the area for nesting, in addition, woody vegetation attracts avian and mammalian predators that may significantly reduce nesting success.

To improve habitat, the U.S. Fish and Wildlife Service (USFWS) has been actively removing trees to:

  1. reduce the amount of acreage taken up by incompatible habitat

  2. to increase the effective field size of adjacent grasslands

  3. to reduce the amount of habitat attractive to avian and mammalian predators that may decrease nesting success for grassland birds.

 When woody vegetation is removed, it is expected that the numbers of grassland nesting birds will increase. USFWS personnel in the Litchfield and Morris Wetland Management Districts have teamed with HAPET to monitor the response of grassland birds to tree removal. Six WPA's have been targeted for tree removal while six similar WPA's will be left as controls to measure natural annual variability in bird numbers. Birds will be counted before and after tree removal to measure their response to the increased habitat availability and larger open spaces.

For an overview and annotated bibliography on the effects of woody vegetation on grassland birds click here.

 For additional information about tree removal for grassland birds contact:

Diane Granfors
Region 7 Inventory and Monitoring Coordinator
U.S. Fish and Wildlife Service
1011 East Tudor Road
Anchorage, AK 99503


Cry of the Marsh
Strategic Habitat Conservation
Last updated: February 22, 2010