The iconic Texas horned lizard (Phrynosoma cornutum) is the state reptile of Texas and was once abundant across the western two-thirds of the state. Since the late 1960s, horned lizard populations have declined or disappeared in many areas due to a variety of factors, including deterioration, fragmentation, and loss of habitat; non-native invasive species such as exotic grasses and red imported fire ants; and pesticide use. Many Texans have fond memories of the Texas horned lizard (aka “horny toad”) and wish for its return to its former abundance.
San Antonio Zoo’s Center for Conservation and Research (SAZCCR) Texas Horned Lizard Reintroduction Project seeks to restore the Texas horned lizard population by working with private landowners to introduce zoo hatched lizards in areas where it has disappeared in recent decades. SAZCCR assesses candidate release sites based on several criteria using remote habitat ranking and boots-on-the-ground surveys. In addition, SAZCCR provides management guidance and assistance to landowners who wish to manage their property for native biodiversity, including horned lizards.
The establishment of viable horned lizard populations requires the production of large numbers of hatchling lizards from SAZCCR’s “Lizard Lab.” The lab is a 450-square foot room and the former receiving bay of the zoo’s warehouse that has been modified to include two sets of timer-controlled power outlets (one for UV lights and one for basking lights) and heavily insulated exterior walls. This room houses all breeder adults and seasonally serves as the “Lizard Nursery” for hatchling lizards.
Young lizards are introduced to the release site in early Fall, and the property is monitored for horned lizard activity at regular intervals. SAZCCR has partnered with Paul Bunker, owner of Chiron K9, to develop the Horned Lizard Detection Canine Network, a group of volunteer handlers and their canines who are trained to find horned lizards. Dogs are trained with live horned lizards, scat, eggs, and shed skin so that they may detect any traces of Texas horned lizards in the field. This partnership with Chiron K9 provides SAZCCR with an efficient long-term method for monitoring lizards post-release and helps to ensure the overall success of the project.
By re-establishing horned lizard populations and encouraging voluntary management that benefits native biodiversity, SAZCCR hopes to improve native biodiversity across Texas and promote awareness and appreciation of this species for the benefit and enjoyment of present and future generations. SAZCCR’s long-term project goal is to develop replicable methodologies to share with other conservation entities to ultimately ensure the return of this beloved species to places where its absence is so deeply felt.
San Antonio Zoo®, operated by San Antonio Zoological Society, is a non-profit organization committed to securing a future for wildlife. Through its passion and expertise in animal care, conservation, and education, the zoo’s mission is to inspire its community to love, engage with, act for, and protect animals and the places they live. The zoo welcomes more than a million visitors each year and is open year-round. San Antonio Zoo is accredited by the Association of Zoos and Aquariums, the Zoological Association of America, and Humane Certified by American Humane.
• On October 9th, 2020, 84 zoo-hatched Texas horned lizards were introduced into a suitable 2,000-acre habitat in Blanco County, Texas.
• 80% of Texans live in areas where the Texas Horned Lizard has been extirpated.
• Over $275,000 contributed through direct funds and research grants to programs geared towards re-establishing horned lizard populations, ecological studies, habitat management, and identifying and mitigating potential causes for the decline.
San Antonio Zoo’s Center for Conservation and Research Texas Horned Lizard Reintroduction Project is supported by a wealth of partners and collaborators, including Amy Shelton McNutt Charitable Foundation, Cesar Kleberg Wildlife Research Institute, Chiron K9 and the Horned Lizard Detection Canine teams, Circle Bar Foundation, Elizabeth Hueth Coates Charitable Foundation, Global Wildlife Conservation, Maltsberger-Storey Family Foundation, Nelson Puett, San Miguel Energy, Texas Christian University, Texas Parks and Wildlife Department, The Nelson Puett Foundation, Toyota Motor Manufacturing of Texas, V. H. McNutt Memorial Foundation, Winkler Family Foundation, Winn Family Foundation, and many other donors and private landowners.
San Antonio Zoo’s Center for Conservation and Research Texas Horned Lizard Reintroduction Project was selected for Texan by Nature Conservation Wrangler based on the project’s positive impact on people, prosperity, and natural resources. Through the program, Texan by Nature is working with the San Antonio Zoo Horned Lizard Reintroduction Project to address the following needs:
• Media visibility to bring awareness to their project and, encourage statewide horned lizard conservation efforts among landowners, businesses, and environmental groups. This media will also connect the project to individuals and foundations who are interested in contributing.
• Volunteers and landowners engage in landscape management practices such as population monitoring, fire ant mitigation, and habitat restoration that benefit the Texas horned lizard and other native species.
• Diverse funding sources to complete the construction of San Antonio Zoo’s “Lizard Lab” breeding facility for the Texas horned lizard. This expansion will allow for the project to quadruple the capacity of our lizard breeding program.
Texan by Nature’s Vision and Support:
Texan by Nature (TxN) is working with San Antonio Zoo’s Center for Conservation and Research (SAZCCR) to connect individual partners and conservation organizations that are working towards the conservation of Texas horned lizards across the state. Texan by Nature aims to help SAZCCR replicate the Texas Horned Lizard Reintroduction project model through sharing best practices, case studies, and habitat management guides to encourage statewide science-based horned lizard conservation efforts among landowners, businesses, and environmental groups.
Contact Texan by Nature at firstname.lastname@example.org & (512) 284-7482 if you can provide resources, connections, are interested in partnering, or would like to learn more.
Figure 1. Ed-ZOO-cation in the park at Crescent Bend Nature Park in Schertz. Children collecting ants that will be fed to horned lizards.
Figure 2. Day-old hatchlings. Hatched on 6/20/2021.
Figure 3. Pairs of lizards mating.
Figure 4. Incubation box containing a clutch of eggs laid on 4/25/2021.
Figure 5. Lizard feeding on harvester ants from an ant feeder.
Figure 6. The Texas Horned Lizard Detection Canine Team at a training weekend. From left to right: Jana Gibbons with Arrow, Chris Bagley with Gren, Dusty Rhoads, Diana Wilkins with Valor, Paul Bunker, and Michelle Peterson with Nenelli.
Figure 7. Paul Bunker’s proprietary scent device for detection dog training.
Figure 8. Installation of additional labs.