| The Conservation Reserve Program (CRP), a ten-year federal agricultural land retirement program, returned several million acres of the Great Plains to grass by 1989. Improvement of wildlife habitat was a secondary but important rationale for the program.; Enrollments are concentrated in the southern High Plains and the northern glaciated Plains. CRP fields increase in size from east to west, with many counties exceeding 320 acres for mean contract size. A study of Plains land use, soils, geology, and climate helped construct a list of expected effects of the CRP on the mammals and breeding birds. The list was revised based on comments from Plains biologists. Most of the species on the Plains depend on woodlands, wetlands, or other cover the CRP does not provide. Some species that use grassland or agricultural land will gain habitat, mainly for nesting.; Nine-section study areas in six Plains counties detailed land cover changes associated with the CRP. Most areas have seen a net increase in cropland since the late 1960s despite the CRP retirements. In some counties, especially far western ones, CRP land is in larger blocks, isolated from woodland and shrubs. These areas favor small to medium sized grassland birds and mammals. CRP parcels in other counties, especially to the east, are well-interspersed with other cover. Mosaic species using grassland, cropland and woodland should benefit there. These include bobwhite quail, white-tailed deer, and some predators.; A dynamic programming model was developed to help investigate the effects of landscape pattern on animal behavior and survival. A preliminary version calculated winter survival of bobwhite quail. Small demonstration areas selected from the study areas suggested that the configuration of CRP fields could be improved to maximize wildlife benefits.; Many of the wildlife benefits of the CRP could vanish after the program expires if farmers return CRP fields to cropland. Other long-term alternatives could prove less costly. Limited federal buy-outs of erosion-prone land may be feasible, especially in expansion of National Grassland. Easements, purchase of cultivation rights, and subsidies for alternative agricultural practices are other tools for encouraging long-term conservation on the Great Plains. |
