<p> Loss and degradation of grassland habitat are driving forces that contribute to widespread declines of grassland birds in the United States. Many studies have evaluated habitat needs for the conservation of grassland birds, but the relative contribution of public lands in representing and maintaining avian biodiversity remains poorly understood. Having a better understanding of the role that publicly managed grasslands play in the conservation of grassland bird habitat is important for assessing the value of the investment the American public makes in these lands, therefore I investigated spatial relations among variations in amounts and distributions of publicly owned and managed grassland habitat and avian species richness. My study focused on two ecoregions, the Northwestern Great Plains and the High Plains, which comprise a substantial portion of the U.S. Great Plains, the continental Central Flyway for migratory bird species. The Great Plains provide critical nesting habitat for grassland birds, however federally owned and managed grasslands are unequally distributed between the two ecoregions, with the Northwestern Great Plains having a greater proportion of federally owned grasslands. I found that, overall, the quantity, size, and connectivity of grasslands were greater in the Northwestern Great Plains, and the region hosted slightly more of the 13 species I studied than did in the High Plains. Both ecoregions, however, sustained roughly half of their respective public lands as grassland. Areas of higher species richness were more widespread in the Northwestern Great Plains ecoregion and were associated with BLM, FWS, and NPS holdings. In the High Plains ecoregion, areas of higher species richness were limited to the northwest within FWS, USFS, and DOD holdings. Areas managed for biodiversity in both ecoregions were not necessarily associated with higher species richness. For example, some areas with the greatest species richness in the High Plains ecoregion were managed for multiple uses, but the onus for conservation of grassland birds need not fall entirely on the federal government. Non-public (privately held) grasslands in the landscapes surrounding public lands can add value to public grasslands by helping to offset habitat fragmentation and small patch size. My analyses found this particularly evident in the High Plains ecoregion, and it speaks to the importance of grassland bird habitat conservation being a joint effort among federal agencies and private landowners.</p>
| Identifer | oai:union.ndltd.org:PROQUEST/oai:pqdtoai.proquest.com:10274392 |
| Date | 01 July 2017 |
| Creators | Siemonsma, Dawn L. |
| Publisher | South Dakota State University |
| Source Sets | ProQuest.com |
| Language | English |
| Detected Language | English |
| Type | thesis |
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