loading page

Predation release of Texas horned lizards (Phrynosoma cornutum) living in small towns
  • Stephen Mirkin,
  • Mary Tucker,
  • Dean A. Williams
Stephen Mirkin
Texas Christian University College of Science and Engineering
Author Profile
Mary Tucker
Texas Christian University College of Science and Engineering
Author Profile
Dean A. Williams
Texas Christian Univ
Author Profile

Abstract

Texas horned lizards (Phrynosoma cornutum) have a number of ways to avoid predation, including camouflage, sharp cranial horns, flattening of the body, and the ability to squirt blood from the eyes. These characteristics and their relatively low survival rates in the wild suggests these lizards are under high predation pressure. These lizards have been declining in much of their eastern range due to increased urbanization, agriculture, and loss of prey species. However, they can be still be found in some small south Texas towns where they can reach densities that are much higher (~50 lizards/ha) than in natural areas (~4-10 lizards/ha). We hypothesized that one reason for the high densities observed in these towns may be due to reduced predation pressure. We used model Texas horned lizards to test whether predation levels were lower in two south Texas towns than on a nearby ranch. We constructed models from urethane foam, a material that is ideal for preserving marks left behind by predators. Models (n = 126) and control pieces of foam (n = 21) were left in the field for 9 days in each location in early and late summer and subsequent predation marks were categorized by predator taxa. We observed significantly more predation attempts on the models than on controls and significantly fewer attempts in town (n = 1) compared to the ranch (n = 60). On the ranch, avian predation attempts appear to be common especially when the models did not match the color of the soil. Our results suggest that human modified environments that have suitable habitat and food resources may provide a refuge for some prey species like horned lizards from predators.

Peer review status:Published

20 Oct 2020Submitted to Ecology and Evolution
29 Oct 2020Submission Checks Completed
29 Oct 2020Assigned to Editor
12 Nov 2020Reviewer(s) Assigned
05 Dec 2020Review(s) Completed, Editorial Evaluation Pending
18 Dec 2020Editorial Decision: Revise Minor
11 Feb 20211st Revision Received
12 Feb 2021Submission Checks Completed
12 Feb 2021Assigned to Editor
12 Feb 2021Review(s) Completed, Editorial Evaluation Pending
12 Feb 2021Editorial Decision: Accept
May 2021Published in Ecology and Evolution volume 11 issue 10 on pages 5355-5363. 10.1002/ece3.7426