Theses and Dissertations - UTB/UTPA

Date of Award


Document Type


Degree Name

Master of Science (MS)



First Advisor

Dr. Timothy Brush

Second Advisor

Dr. Frank W. Judd

Third Advisor

Dr. Robert I. Lonard


Habitat fragmentation has been shown to have negative effects on avian communities. I looked at the effects of corridor width and vegetation characteristics on nesting densities and breeding success of birds in the Lower Rio Grande Valley. There were definite trends in this study of increasing species richness and nesting densities with increasing corridor widths. Multiple regression revealed little correlation between tree density, diameter at breast height, tree height, canopy cover and ground cover with nesting density or nesting success. However, factors such as parasitism by the Bronzed Cowbird (Molothrus aeneus) and predation were much greater in narrower corridors. This study indicates that present corridors are too narrow and that Lower Rio Grande riparian forest and its avian community are reverting to drier mixed forest.


Copyright 1997 Jeffery R. Rupert. All Rights Reserved.

Granting Institution

University of Texas-Pan American