Erin Schillings

Document Type

Honors Thesis


The Texas horned lizard, Phrynosoma cornutum, is classified as a threatened species. They are known by the horns on their head and as the state reptile of Texas. This flat-bodied and fierce-looking lizard is important to our ecosystem by limiting the ant population, but is falling prey to larger predators, such as coyotes and rattlesnakes. To further conserve the species and study the population size, a team of researchers went to west Texas to capture and mark lizards with electronic Passive Integrated Transponder (PIT) tags. They had an encounter number of 164 from 2010-2021. The data consisted of: GPS coordinates, sex, gravid, Snout-Vent Length, total length, weight, temperature, and route data. The data was run through the MARK program to show the estimated population size and promote steps to preserve the diversity of the species. The findings show that the species has a healthy population in Roby, Texas due to conservation and rehabilitation efforts.

Publication Date




Faculty Mentor of Honors Project

Corey Roelke



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