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


The Elf Owl, Micrathene whitneyi, is a regular summer resident of the southwestern United States. My objectives were to collect information concerning habitat selection, home range size, and population density of M. w. idonea, the subspecies occurring in the Lower Rio Grande Valley of Texas. Nocturnal surveys indicated greater use of chaparral habitat (92%) compared to riparian woodlands (8%). Utilized habitat was characterized by highest foliage density at 2.5-3.0 m, with a partial canopy at 3.8 $\pm$ 0.36 m and a semi-open understory. Home range size ranged from 0.24 to 2.6 ha, with a mean of 1.05 $\pm$ 0.33 ha. Estimated maximum population size within Santa Ana National Wildlife Refuge is 802 Elf Owls.


Copyright 1997 Christopher Michael Gamel. All Rights Reserved.

Granting Institution

University of Texas-Pan American