Theses and Dissertations

Date of Award


Document Type


Degree Name

Master of Science (MS)


Agricultural, Environmental, and Sustainability Sciences

First Advisor

Dr. Christopher Gabler

Second Advisor

Dr. Timothy Brush

Third Advisor

Dr. Alex Racelis


The Rio Grande Valley of Southern Texas is a major agricultural region yet has some of the highest hunger rates in the USA. Urbanization and agriculture affect biodiversity, which is well studied, but little is known about how agriculture affects biodiversity in urban areas. We investigated how different urban attributes, including those related to urban farming, impact bird communities in Brownsville and Harlingen, TX, and compared sites that have community gardens to those that do not. To study three key urban habitat characteristics, we identified sites that exhibited all possible combinations of these factors, quantified land cover classes related to these factors at each site, and surveyed bird communities at each site on three separate days in 2017. To determine which factors influenced bird communities, we constructed ANCOVA models that included our three factors and ground cover values, and then used post-hoc pairwise tests to compare community gardens to other sites.


Copyright 2018 Samuel Glenn Ortiz. All Rights Reserved.