Avian use of fencerow habitat in a predominantly agricultural area /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1989.
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| Subjects: | |
| Online Access: | Link to ProQuest copy Link to OAKTrust copy |
| Abstract: | I censused 13 fencerows in a highly cultivated area of Burleson County, Texas from August 1983-June 1985 to determine seasonal use of fencerows by birds, including changes in species richness and abundance and the association of these changes with vegetation structure. Four grass, 5 shrub, and 4 tree fencerows were censused using a modified strip census method to record species and numbers of individuals and the vegetation in which they were observed. Count data were analyzed by associating numbers of species and individuals with fencerow type, census section type, and vegetation volume. Vegetation volume was calculated for tree, shrub, and grass layers and for each of 3 strata. Eighty one species were censused in fencerow vegetation. Although more species and individuals used tree fencerows and shrub fencerows with grass fencerows having the fewest, utilization-availability analyses based on vegetation volume indicated the grass and shrub layers were used at or above the expected levels for some seasons. Cardinal nest success, nest site selection, and territory size and shape were compared between 12 fencerow territories and 14 cardinal territories in a nonlinear habitat for the 1984 and 1985 breeding seasons. No statistically significant differences were found when comparing eggs/nest, young/nest, or fledged/nest nor by comparisons of daily survival rates, although fencerow cardinals had larger clutches, higher daily survival rates, higher probabilities of surviving from egg laying to fledging, and fledged more young/pair. Heavy predation masked differences in nest success. Nonlinear cardinal territories were significantly larger than fencerow cardinal territories and had irregular polygon shapes. Fencerow territories were essentially limited to the fencerow vegetation with linear, rectangular, or triangular shapes when intersecting with perpendicular fencerows. Size of fencerow territories did not increase as a result of less vegetation, suggesting song points may be the principal factor in cardinal territory selection.. |
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| Item Description: | "Major subject: Wildlife and Fisheries Sciences." Typescript (photocopy). Vita. |
| Physical Description: | xv, 157 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |