Theses and Dissertations - UTB/UTPA
A comparison of secondary successional woody vegetation in two revegetated fields in South Texas and an assessment of habitat use by the olive sparrow, Arremonops rufivirgatus
Date of Award
Master of Science (MS)
Dr. Robert I. Lonard
Dr. Timothy Brush
Dr. Jacobo Ortega
Aspects of plant species composition and structure of two revegetated fields in western Cameron County, Texas, were studied between 1992 and 1995. Avian habitat suitability was assessed using the Olive Sparrow, Arremonops rufivirgatus, as an indicator species. Total vegetation volume at the Longoria Wildlife Management Area (WMA), an area revegetated in 1961, was 0.745 $\rm m\sp3V/m\sp2$ and that of the Anacua WMA, revegetated in 1983-4, was 0.546 $\rm m\sp3V/m\sp2$ in 1992. Secondary woody species at the Longoria and Anacua WMA's had a Shannon's index of diversity of 0.619 and 0.264, respectively. Secondary woody vegetation at the Longoria WMA had a Simpson's dominance value of 0.34 and the dominance of the secondary woody vegetation at the Anacua WMA was 0.66. Olive Sparrow densities at the Longoria and Anacua WMA's were 2.5/ha and 0.5/ha, respectively. The greater secondary woody species diversity, smaller dominance, and higher density of Olive Sparrows found at the Longoria WMA were likely due to the greater age and density of the vegetation as well as the primary plant species introduced. A greater total vegetation volume and secondary woody species diversity appear to provide a more suitable habitat for the Olive Sparrow. It is likely that a greater diversity of avian species, including neotropical migrants, would be attracted to similar revegetated sites in this region, as such habitats mature.
University of Texas-Pan American
Copyright 1996 Patrick Grant Wright. All Rights Reserved.