Biology ETDs

Publication Date



The largest and most dominant kangaroo rat species in the Chihuahuan Desert is the banner-tailed kangaroo rat (Dipodomys spectabilis). This keystone species constructs mounds containing a complex burrow system around which their ecosystem engineering activities are centered. I studied a population of banner-tailed kangaroo rats at the Sevilleta National Wildlife Refuge, New Mexico from 2005-2009. Specifically, I examined how banner-tailed kangaroo rats: 1) modify their mounds in response to seasonal conditions; 2) spatially affect harvester ants (Pogonomyrmex rugosus) through ecosystem engineering activities; and 3) differ in timing of natal dispersal between sexes. I used mark-recapture, genetic, experimental, and spatially-explicit methods to address these areas of interest. I observed that kangaroo rats remodeled their mounds seasonally in relation to changes in predation risk, seed spoilage risk, and metabolic costs. My results documented an additional keystone effect of banner-tailed kangaroo rats in the Chihuahuan Desert, a facilitatory impact on the spatial structure and dynamics of harvester ant colonies. I also experimentally determined that physiological cues influence timing of natal dispersal in males and females differently.

Project Sponsors

Sevilleta LTER



Document Type


Degree Name


Level of Degree


Department Name

UNM Biology Department

First Committee Member (Chair)

Brown, James

Second Committee Member

Smith, Felisa

Third Committee Member

Roemer, Gary