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2. Evaluate effects of various frequencies (interval between successive treatments) and timing (spring or fall) of mowing, grazing, and burning on habitat use, nesting density, and reproductive success of grassland-nesting birds. Additional research on effects of mowing is especially needed for the western meadowlark, dickcissel, vesper sparrow, and lark sparrow; effects of grazing for the dickcissel, grasshopper sparrow, and ring-necked pheasant; and effects of burning for the upland sandpiper, bobolink, eastern meadowlark, dickcissel, Savannah sparrow, vesper sparrow, lark sparrow, and ring-necked pheasant.

3. Determine the optimal size of a grassland management unit (percent of area treated) in terms of use, nesting density, and reproductive success of grassland-nesting birds.

4. Evaluate effects of woody vegetation control, and lack thereof, via various methods (mowing, burning, treating with herbicide) on habitat use, nesting density, and reproductive success of grassland-nesting birds.

5. Evaluate effects of agricultural chemicals applied to crop fields and adjacent grasslands on breeding habitat quality (vegetation composition and structure and insect abundance and biomass), habitat use, nesting density, and reproductive success of grassland-nesting birds.

6. Examine effects of edaphic factors, topography, and vegetation type on habitat management practices (mowing, grazing, and burning) and relate them to habitat use, nesting density, and reproductive success of grassland-nesting birds.

7. Examine effects of landscape diversity and pattern on the composition and dynamics of the grassland bird community.

8. Determine minimum area requirements and sensitivity to habitat fragmentation for each species of grassland-nesting bird and evaluate effects of habitat type (e.g., warm-season grasses, cool-season grasses, legumes, mixed grass-legume, and savannah), vegetation composition and structure, adjacent land-use practices, species interactions, and various management schemes (frequency and timing of mowing, grazing, and burning) on minimum area requirements of each species.

9. Evaluate the influence of grassland area, vegetation composition and structure, insect abundance and biomass, adjacent land-use practices, and species interactions on habitat use, nesting density, and reproductive success of grassland-nesting birds. Use this information to identify what attributes characterize grasslands that support source and sink populations of grassland-nesting birds.