Will Conversion of Conservation Reserve Program (CRP) Lands to Pasture be Detrimental for Grassland Birds in Kansas?

Abstract

-The Conservation Reserve Program (CRP) was established by the 1985 Food Security Act (Farm Bill). Unless renewed, most CRP contracts will expire in 1997 and up to 70% of CRP fields in Kansas may be converted to pasture. We compared avian use of CRP areas with that of pasture to determine if such conversion would be detrimental to grassland birds. Data on vegetative structure, avian abundance, and avian reproductive success were collected on five CRP fields and five pastures during summer 1993. Pastures had significantly greater vegetative cover and CRP fields had more bare ground. Vegetation was significantly taller in CRP fields late in the summer. Total avian abundance and that of dickcissels, grasshopper sparrows, meadowlarks, brown-headed cowbirds and upland sandpipers were greater in pastures than in CRP fields. Reproductive success and rates of nest parasitism by brownheaded cowbirds did not differ between the habitats, but nests were more numerous in grazed pastures. If the CRP is not reauthorized in the 1995 Farm Bill and most of the Kansas land currently enrolled in CRP is converted to pasture, the conversion probably will not be detrimental to grassland bird populations if the land is moderately grazed.