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Description:
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The objective of this study was the assessment of the importance of the shrub component on small mammal composition and abundance in a sand shinnery oak (Ouercus havardii ) ecosystem in Yoakum County , Texas . Shrubs were removed in two areas via the application of tebuthiuron at the rate of 1 /2 lb . per acre . Tebuthiuron is an herbicide which will eliminate at least 90 % of the shrub component in a sand shinnery oak ecosystem without damaging other components of the plant community . A "trapping web" (Anderson et al . 1983 ) was used to obtain a direct estimate of rodent density in each shrub removal site , as well as on each of the two control sites . Densities were then statistically compared . Because of low sample size , other population estimation techniques also were used for statistical purposes . Vegetation sampling also was done to determine the ecological variables associated with small mammal population responses . Trapping and vegetation sampling were performed during the four phenological periods of the area . Population sizes were not found to significantly differ in the treated and untreated areas . Species composition was not conclusively different in the treated and untreated areas . Overall , the shrub component in the sand shinnery oak ecosystem was found to have little effect on the small mammal populations . Rodent populations were effected more by season than by shrub removal . |