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Project Prairie Birds

A Citizen Science Project for Wintering Grassland Birds

Size of Grassland

Long Prairie Grasses

There is no minimum field size, but at least the 20 x 100 m transect must fit. The following are acreage size classes for grassland sites. This is an estimate of contiguous patch size and homogeneity of the area as you are standing in your transect. In other words, when you look around, does the habitat change dramatically or does it all appear the same to you? If you need assistance, consult the landowner or land manager for these figures.

Photo Killdeer Copyright Michael L. Gray

Photo Copyright Michael L. Gray


  1. < 1-5 acres (1 acre is roughly the size of a football field)*
  2. 6-10 acres
  3. 11-50 acres
  4. > 100 acres

* An acre is roughly 64 m (208 feet). Actually, 208.71 feet = 43,560 square feet, but a football field is 160 feet X 300 feet = 48,000 square feet making the football field less then 10% larger then one acre.

Grasslands are usually not homogeneous and can include several microcommunities.

The picture below shows the preferred microhabitat where most individuals of selected grassland species occur. NOTE: With every rule in the biological world, there is an exception. This is generally where each species occurs, but not exclusively. Bird abbreviation descriptions may be found on Grassland Species page.

For Additional Information write to:

Project Prairie Birds Program
Texas Parks and Wildlife Department
4200 Smith School Road
Austin, TX 78744
or send a message to: