Ring-Necked Pheasants and Passerine Abundance in Conservation Reserve Program Grasslands of Differing Age-Classes and Cover Types in Eastern South Dakota, 1998-2000

During the past 50 years increasing agricultural practices have transfonned native habitat into row-crop fields, thus making the Conservation Reserve Program (CRP) grasslands very important to numerous wildlife populations. Limited information exists on how the ring-necked pheasant (Phasianus colchicus) and passerine bird species relate to different stand ages and cover types of CRP. CRP grassland study sites (n=42) were stratified by low and high pheasant density areas, CRP stand age (old [I 0-13 years] versus new [0-3 years] grasslands), and cover types (CPI-cool-season grasslands versus CP2- warm-season grasslands) in eastern South Dakota. Twenty-two row-crop fields were also surveyed (11 com and 11 soybean). Pheasant crowing counts were conducted 3 times annually and roadside pheasant brood counts were conducted 4 times annually. Passerine bird sampling was conducted once each year in I 00 x 1 OOm belt transects and vegetation sampling was conducted twice each year. Old grasslands had higher crowing counts than new grasslands or row-crop fields. New grasslands had slightly higher crowing counts than row-crop fields. Cool-season grasslands in the high pheasant density area had the highest crowing counts. The highest number of broods was observed in 1998 in the high pheasant density area in old CRP grasslands. Cool-season grasslands had more broods associated with them than warm-season grasslands. A total of thirty-two non-game bird species were observed in CRP grasslands and row-crop fields. CRP grasslands had higher species density and species richness than row-crop fields. Red-winged blackbirds (Age/aius phoeniceus), dickcissels (Spiza Americana), brown-headed cowbirds (Molothms ater), western meadowlarks (Sturnella neglecta), and bobolinks (Dolichonyx oryzivoms) were the most abundant species in the CRP grasslands. Red-winged blackbirds, western meadowlarks, homed larks (Eremophi/a a/pestris), and dickcissels were the most abundant birds in the rowcrop fields. Seventeen species were identified in old grasslands, while 23 species were observed in new grasslands. Nineteen bird species were detected in cool-season grasslands, whereas 23 species were observed in warm-season grasslands. Grassland obligate species were more abundant in cool-season CRP grasslands, whereas for the generalist/woodland edge species there was no difference in abundance between cover types. Based on my findings, I submit that extending I 0-year contracts for another 5-10 years is justified relative to pheasants and non-game birds. I also recommend that USDA administrators and field staff provide broader and more flexible guidelines on what seed mixtures are to be used in CRP grassland plantings in the northern Great Plains. My findings show that cool-season grass/legume mixtures (CPI) support higher pheasant productivity and higher grassland bird richness, and thus should be given equal or higher ratings than warm-season (CP2) grass stands