Theses and Dissertations

Date of Award


Document Type


Degree Name

Master of Science (MS)



First Advisor

Dr. Timothy Brush

Second Advisor

Dr. Andrew McDonald

Third Advisor

Dr. Teresa-Patricia Feria-Arroyo


The objective of this investigation was to examine the foraging patterns and population density of the Buff-bellied Hummingbird (Amazilia yucatanensis ) in Hidalgo County, TX. Previous studies showed that hummingbirds use flowers displaying traditional bird pollination (ornithophilous) characteristics: reddish coloration, tubular corolla, and extended anthers. Observation sessions noted type and frequency of flowering species utilized for nectar, characteristics, and number of individuals seen in each area. Amazilia yucatanensis showed higher use of ornithophilous flowers. Significant results found: f-ratio 5.45 > p-value (0.05) 3.24. Two highly utilized species showed the expected 20–40% sucrose content expected in ornithophilous flowers. Population density per hectare was high during summer (0.043) and fall (0.042), decreased in winter (0.11), and rose in spring (0.17). Although data gathered here supported the preference for ornithophilous flowers, further study is needed to determine if similar patterns occur in other locations throughout the Lower Rio Grande Valley.


Copyright 2016 Megan I. Villarreal. All Rights Reserved.

Included in

Ornithology Commons