The Texas Horned Lizard Advocacy Guide is intended as an
information resource for individuals who wish to support the restoration of
the Texas horned lizard (Phrynosoma cornutum). The Texas Horned Lizard
Reintroduction Project at the Center for Conservation and Research at San
Antonio Zoo was selected as a Texan by Nature Conservation Wrangler.
This guide is a result of this collaboration and created with the help of thefollowing organizations:

Please contact conservationinfo@sazoo.org if you have informationthat could be updated and/or added to this guide.

TABLE OF
CONTENTSSUMMARY............................................................................... 3
ABOUT THE TEXAS HORNED LIZARD.................................. 4
WHAT IS THE TEXAS HORNED LIZARD?........................ 4
WHERE ARE THEY FOUND?............................................. 6
WHY DID THE POPULATION DECLINE?......................... 6
WHAT CAN I DO TO HELP HORNED LIZARDS?.................. 10
BECOME A COMMUNITY SCIENTIST........................... 10
LET WILDLIFE STAY WILD............................................. 11
SPREAD THE WORD...................................................... 12
MANAGE YOUR BACKYARD.......................................... 13
COLLECT TEXAS HORNED LIZARD SCAT..................... 15
MAKE A MONETARY DONATION................................. 17
RESOURCES FOR LANDOWNERS........................................ 18
CONCLUSIONS..................................................................... 19
CONTACT INFORMATION.................................................... 20
WORKS CITED....................................................................... 23

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Texas Horned Lizard Advocacy Guide
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SUMMARYABOUT THE TEXAS HORNED LIZARD:The Texas horned lizard is a charismatic species, and theiconic state reptile of Texas. While this species was once
found throughout most of the state, they have disappeared
from at least 30 percent of their historic range in the past
40 years. While there are many factors that have led to thisspecies decline, the most significant causes are urbanizationand the introduction of invasive species, both of which
drastically reduced the quantity and quality of habitat for
Texas horned lizards (see pages 4-9 for more details about
this species and their decline).

HOW CAN I HELP?
While the Texas horned lizard has disappeared from many
places, there is still a lot that can be done to help thisspecies. Documenting sightings, collecting scat, and donating
to established reintroduction projects are just some of theways you can help ensure these beloved lizards are aroundfor future generation to enjoy (see pages 10-17 for more
information and suggestions). If you are a horned lizardloving landowner and are interested in managing yourproperty to benefit Texas horned lizards, see page 18 forland management resources. Please read through the restof this guide to learn more about these reptiles, and all theways you can become a Texas horned lizard advocate!

3Texas Horned Lizard Advocacy Guide
Created By: San Antonio Zoo in partnership with Texan by Nature

About the
Texas Horned Lizard

WHAT IS THE TEXAS HORNED LIZARD?
The Texas horned lizard (Phrynosoma cornutum) is one of fourteen
species of horned lizards that are distributed from Southern Canada toSouthern Mexico. The scientific name Phrynosoma means “toad-body”
and cornutum means “horned” and though often referred to as “hornedfrog” or “horny toad”, they are actually reptiles, not amphibians. This
beloved species has been recognized as the state reptile of Texas since
1993 and is listed as threatened at the state level.
Texas horned lizard measures three to five inches long, and ischaracterized by having multiple horns on the back of its skull, the twocentermost horns being most prominent, and it has two rows of spiky
fringed scales that line either side of its body.
As dietary specialists, they feed predominantly on red harvester ants
(Pogonomyrmex barbatus), found throughout the majority of theirhabitat range. They have a sticky tongue that is specialized to catchants quickly and effectively, and have even developed a resilience tomost native ant toxins. Texas horned lizards live in grasslands anddeserts with little water and they have adapted several traits that allow
them to survive in these harsh environments.

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Texas Horned Lizard Advocacy Guide
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One of these adaptations is their specialized skin whichallows them to access water from sources such as moist
sand and dew. The rough scales along their back serve asa funnel that collects and transports the water towards
the lizard’s mouth. This fluid transport is passive, meaningit allows the horned lizard to save energy that would
be spent on finding water, and utilize it for things likemating, foraging, and predator defense.
The predator defense mechanisms of the Texas horned
lizard are quite extraordinary. The lizard’s first line ofdefense is camouflage. The reptiles are so well adapted
to blend perfectly into their surroundings that often
predators do not even notice their presence. If this firstline of defense fails, the lizards have the ability to “puffup” their typically flat abdomen, causing their spines
to protrude, appearing more intimidating and larger
than normal, decreasing their chances of predation.
An additional defense,and possibly the mostremarkable, is the Texas
horned lizard’s ability toshoot blood out of tissues
in their eye sockets. The
fluids have a noxious taste,and cause certain predators
to retreat. This defense
is most effective against
encounters with wild canids,
such as coyotes.

5Texas Horned Lizard Advocacy Guide
Created By: San Antonio Zoo in partnership with Texan by NatureWHERE ARE THEY FOUND?
The map below shows the distribution (depicted by red shading) of
the Texas horned lizard across a wide part of central North America.
The state reptile could once be easily found throughout most of Texas,
but has now disappeared from at least 30 percent of its historic range.
Recent sightings (shown by red squares) are mostly recorded in thenorthern, central, and western portions of the state.

WHY DID HORNED LIZARD POPULATIONS DECLINE?
Many factors threaten the distribution of Texas horned lizards,
including the effects of invasive species, fragmentation and loss ofhabitat, overuse of pesticides, and large-scale agriculture. Changes inland management practices in recent decades have resulted in woody
encroachment of much former horned lizard habitat. In summary, there
is no single cause for the decline of the Texas horned lizard.

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Texas Horned Lizard Advocacy Guide
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INVASIVE SPECIESBoth invasive plants and animals negatively impact Texas horned
lizard populations. Non-native invasive grasses such as KR Bluestem(Othriochloa), were introduced from Europe and Asia in the 1920s
and 1930s as forage for livestock and erosion control. These exotics
grow in dense patches that restrict lizard movement, exclude native
grasses and forbs, and typically support a lower density and diversityof arthropods.

Red Imported Fire Ant(Solenopsis invicta)

Red Imported Fire Ant Mound(Solenopsis invicta mound)

Ant Size: 2 – 6 mm | 0.08 – 0.2 inAnother harmful invasive species is the red imported fire ant(Solenopsis invicta) which was accidentally introduced to the U.S. fromSouth America in the 1930s via cargo ships entering Mobile, Alabama.
Since then, these voracious insects have spread to more than 320
million acres across fifteen states.

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Texas Horned Lizard Advocacy Guide
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Due to their aggressive foraging behavior, high reproductive
capability, and lack of predators and/or other strong competitors,
red imported fire ants often become the dominant ant species inareas outside of their native range. These invasive ants impact
native insects and other terrestrial organisms, including harvester
ants, reducing the amount of food available for horned lizards to eat.

The Beneficial Red Harvester Ant(Pogonomyrmex barbatus)

The Beneficial Red Harvester Ant Nest
(Pogonomyrmex barbatus nest)

Ant Size: 5 – 7 mm | 0.2 – 0.3 inTexas horned lizards are unable to consume red imported fire ants
and these invasive ants have even been known to attack vulnerable
horned lizard hatchlings. Because of this, horned lizard populations
have little or no
success in areas
where this invasive
species is present
at high densities.

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Texas Horned Lizard Advocacy Guide
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HABITAT FRAGMENTATION AND LOSSThe greatest decline of horned lizard populations in
Texas occurred between the late 1960s and early 1970s
as cities grew and surrounding communities became
more urbanized.

9•

Urbanization of rural areas in Texas lowers theamount of suitable grassland and savanna
habitats. Horned lizards struggle to findappropriate protective groundcover in areas of
predominantly nonnative grasses, such as St.
Augustine, which many people use to sod theirresidential lawns.

•

Much like most other wildlife species, horned
lizards often fall victim to moving vehicles on
paved roads, and the number of highway
miles in Texas has more than doubled from35,000 miles to over 79,000 miles since
1935.

•

Urbanization also contributes to habitat
fragmentation by creating isolated andless genetically diverse populations ofTexas horned lizards that are more
susceptible to population pressures.

•

An additional effect of urabanization
is increased pesticide use which
greatly diminishes native harvester
ant populations, reducing foodavailability for horned lizards.

Texas Horned Lizard Advocacy Guide
Created By: San Antonio Zoo in partnership with Texan by Nature

What Can I Do To Help
Horned Lizards?

BECOME A COMMUNITY SCIENTIST
Through community science, the general public can assist scientists
in addressing real-world problems by collecting and analyzing data,interpreting results, and making new discoveries.

One way to participate in community science is through iNaturalist.
iNaturalist is an online community of naturalists, community
scientists, and biologists, built on the concept of mapping and sharing
observations of biodiversity across the globe. With over one million
registered users, this platform serves as a comprehensive database thattracks global plant and wildlife biodiversity and abundance. You canhelp with the conservation of threatened and endangered species, likethe Texas horned lizard, by creating an iNaturalist account to record
your observations. If you come across a Texas horned lizard, eggs, scat(feces), or even shed skin in the wild, take a photo and upload yourfindings to the online platform. By keeping a public record of sightings,
wildlife biologists are able to better determine the most accurate andup-to-date population distribution of the species.
The platform automatically obscures precise location informationfor observations of threatened and endangered species.
Only administrators can view actual location information.

Texas horned lizard hatchling with U.S. quarter

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Texas Horned Lizard Advocacy Guide
Created By: San Antonio Zoo in partnership with Texan by NatureLET
WILDLIFE

STAY
WILD

The Texas horned
lizard is listed as a threatened
species in Texas. Handling Texas horned lizards isillegal in Texas, and even if your intentions are good, you
are in violation of the law and could be ticketed for youractions. Scientists are required to obtain scientific researchpermits from the Texas Parks and Wildlife Department prior
to handling and/or conducting research on Texas horned
lizards (TPWD: Wildlife Diversity Permits: Scientific Permits
for Research).
The greatest way to appreciate wildlife is by maintaining asafe distance, observing the animal in its natural habitat,
and taking photos.

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Texas Horned Lizard Advocacy Guide
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SPREAD THE WORD!
Through educating the American population on the plightof the Texas horned lizard, we can provide these reptiles withsafe and supportive habitats to sustain healthy populations.
Education is crucial to get young Texans excited about their state
reptile. By learning about the Texas horned lizard and sharing
your knowledge with the world, you are acting as an advocate
for the species, perpetuating a lasting spirit of conservation for
future generations. So, start today by spreading the word of
Texas horned lizard conservation across the state!
Outreach events hosted by the Center for Conservation andResearch at San Antonio Zoo provide the general public withthe opportunity to see Texas horned lizards and learn more
about their history in and around the state of Texas. Nationalorganizations like the Horned Lizard Conservation Society (HLCS),
as well as other Zoological facilities, such as the Dallas Zoo, also
have great educational resources for conservationists of all ages.

Collecting

Harvester ants at

a San Antonio Zoo
ED-Zoo-Cationin the park Event

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Texas Horned Lizard Advocacy Guide
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MANAGE YOUR BACKYARD
You can make your land more habitable for Texas horned lizards andother native species by making simple changes to take care of yourproperty in a sustainable way, like reducing pesticide use, planting
native plants, and removing invasive species. These steps do notnecessarily guarantee that horned lizards will return to your property,
but sustainable land management practices will help a variety of different
native species, such as birds and pollinators.

Recommendations:•

Treat fire ant mounds without the use of pesticides.
While horned lizards depend on native harvester ants for food, invasive
fire ants are harmful to horned lizards and other wildlife. Fire ants arecommon in suburban neighborhoods, and management without theuse of pesticides is imperative in maintaining a healthy ecosystem. To
individually treat each mound, drown the area with a bucket of very
hot water and a bit of dish soap, digging the water in with a shovel.
Remember to wear protective equipment such as gloves, closed-toedshoes, and long pants to protect yourself from ant bites and stings.
For more information on managing for Red Harvester Ants and fire ant
mitigation, Texas Parks and Wildlife has published a guide outlining
their strategies for ant management.

!
y
m
yum

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Texas Horned Lizard Advocacy Guide
Created By: San Antonio Zoo in partnership with Texan by Nature• Keep cats indoors and keep all pets away fromwildlife. Another group of invasive animals thatcan negatively impact the population of horned
lizards and other wildlife is unsupervised pets.
When left outside without supervision, dogs andcats can prey upon or cause harm to native animals
in residential and urban areas.
• Landscape your yard using native plants.
Native plants provide many benefits to theecosystem- improved soil health, habitat for native
pollinators, and even water conservation, whichsaves you money. Texas A&M AgriLife Extension
provides resources on which native plant species				are best to plant in your area.

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Texas Horned Lizard Advocacy Guide
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COLLECT TEXASHORNED LIZARD SCATThe Horned Lizard Detection Canine
Network is a group of volunteer handlers
and their canines who are trained to findevidence of Texas horned lizards. Dogs
are trained with live horned lizards, scat(poop), eggs, and shed skin so that they may
detect any traces of Texas horned lizards
in the field. This partnership with Chiron
K9 provides CCR with an efficient long-term
method for monitoring lizards post-releaseand helps to ensure the overall success ofthe project.

Horned Lizard

Detection K9, “Gren” hasbeen trained to cue on thescent of horned lizard scat.

To assist the Horned Lizard Detection Canine Network you can collect scatto send to Chiron K9 for dog training. To do so you may make your own
kit (see how here: Horned Lizard Scat Collection - YouTube) or you canemail Paul@Chiron-K9.com to have a kit sent to you.

Please ensure the following when collecting Texas horned lizard scat:•

Only collect Texas horned lizard poop – See above video for examples.

•

Do not touch samples – Use clean tweezers, and/or plastic disposable
gloves•Use a glass jar – Must be cleaned prior to use.

•

Store in the fridge or freezer – Maintains freshness and preserves
scent.

•Do not touch or disturb horned lizards.

•

Contact Chiron K9 once you have obtained samples– Paul@Chiron-K9.com

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Texas Horned Lizard Advocacy Guide
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The TCU Horny Toad Project also utilizes scat in some of theirstudies. Horned lizard scat is a valuable source of DNA from horned
lizards and provides a good record of their diet. If you are interested
in providing fresh samples to our laboratory send an email to Dean
Williams at dean.williams@tcu.edu to first determine if you are in
an area of Texas we need samples from. If so, he can send you a kit
with collecting vials containing preservative and instructions on how
to collect the sample.

Close-up image ofhorned lizard scat,composed almost
entirely of ants

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Texas Horned Lizard Advocacy Guide
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MAKE A MONETARYDONATION•

Donate an Inspired Gift to support the Center for Conservation
and Research at San Antonio Zoo Texas Horned Lizard
Reintroduction project. You can be an integral part of the
program by choosing to donate from a variety of husbandry
options, such as feeding, hatching, and even outfitting a home
for a horned lizard in the Zoo’s “Lizard Lab”.

•

Order a Texas Parks and Wildlife Department
Conservation License Plate. $22 out of the yearly $30
registration fee goes directly toward TPWD conservation
initiatives. Your donation will help conserve wildlife diversity byfunding a vast array of projects that help protect native species
and their habitats.

•

Become a member of the Horned Lizard Conservation Society.
Support the HLCS mission to study, document and publicize thevalue and conservation needs of horned lizards, promote horned
lizard conservation projects, and assist with horned lizard
management initiatives throughout their ranges.

•

Utilize AmazonSmile. You can choose from a variety of different
organizations such as the Horned Lizard Conservation Society,
San Antonio Zoological Society, Dallas Zoological Society, andTexas Parks and Wildlife Foundation as your charity to support
on AmazonSmile. The organization ofyour choice will receive a donationof 0.5% from all of your eligible
Amazon purchases.
Purchase merchandise to support
the TCU Horny Toad Project.
Proceeds go towards funding forfield research.

•

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RESOURCES FOR LANDOWNERS
If you are a landowner, and would like to learn more about management strategies
for horned lizards, please refer to the following resources:• If you are interested in utilizing your land as a reintroduction site, please fill out thisbrief Landowner survey so that the San Antonio Zoo Center for Conservation andResearch can determine if you meet the habitat requirements. A member of the CCR
team will be in touch once your survey has been submitted.

• TPWD: Find a Wildlife Biologist. The quickest and easiest way to learn more about

how you can help wildlife on your land is to form a relationship with a TPWD Wildlife
Biologist working in your county. TPWD Wildlife Biologists are the most knowledgeable
and valuable resource when it comes to management strategies on private lands.

• The Texan by Nature Landowner Guide is a comprehensive list of state, federal, andNGO programs for conservation restoration, as well as resources for project planningand recognition for your efforts.

• Texas Horns (RehorningTexas.com) is a prairie wildlife management business conceptthat specializes in helping landowners and land managers who want to help restore
Texas Horned Lizard populations and habitat. They help landowners in Texas withevery aspect of habitat and population restoration and monitoring, including working
with zoos for reintroduction, land and lizard surveys, developing wildlife management
plans, and helping landowners achieve a wildlife tax valuation status for their land byimproving the land for Texas Horned Lizards and their habitat needs, among otherservices. Contact email: dusty@rehorningtexas.com.

• The Caesar KIeberg Wildlife Research Institute at Texas A&M Kingsville Managementof Texas Horned Lizards bulletin outlines the ecology and habitat requirements of
the Texas Horned Lizard, and management practices are suggested that should benefit
the species.

• The Texas Parks and Wildlife Department Texas Horned Lizard Management andMonitoring packet is a product of the Texas Horned Lizard Watch program, created toencourage volunteers to participate in horned lizard data collection and research.

• If you have existing red harvester ant mounds on your land, Texas Parks and Wildlife
has also published a detailed guide outlining their strategies for management of the
red harvester ant.

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CONCLUSIONS
If sustainable land management practices are not put into place,
we could lose the official state reptile and a beloved cultural iconof Texas. This iconic species should be protected at all costs. By
supporting conservation programs like the Center for Conservation
and Research at San Antonio Zoo’s Texas Horned Lizard
Reintroduction Project, YOU can help to rebuild the population
to its historic abundance. Through educating the public about thisspecies, collaborating on creative solutions for reintroduction, andimplementing proven land management strategies, we have a chance
to amplify the message of statewide conservation and restore thepopulation of Texas horned lizards.

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Contact Information
TEXAN BY NATURE
Email: info@texanbynature.org
Program webpage: https://texanbynature.org/projects/san-antonio-zoo-center-for-conservation-and-research

Texan by Nature unites conservation and business leaders who believe Texas’ prosperity
is dependent on the conservation of its natural resources. TxN amplifies projects
and activates new investment in conservation which return real benefits for people,
prosperity and natural resources. Texan by Nature achieves mission goals through the
Texan by Nature Certification program, Conservation Wrangler program, Symposia
series, and Texan by Nature 20.
Get involved and learn more at www.texanbynature.org
and follow on									 @TexanbyNature

CENTER FOR CONSERVATION AND RESEARCH
AT SAN ANTONIO ZOOEmail: conservationinfo@sazoo.org
Program webpage: https://sazoo.org/zoo-conservation-efforts/texas-horned-lizard
Center for Conservation and Research at San Antonio Zoo seeks to fulfill our mission
through fieldwork and captive husbandry of rare and threatened species. Much of ourwork is collaborative, involving partners from state andfederal agencies, academia, and the private sector. The
scope of our efforts includes projects on three continents
and projects throughout the United States – with particularemphasis on Texas. Current projects focus on fish,
amphibians, reptiles, insects, crustaceans, and imperiled
ecosystems and cultures. The results of this work include
management recommendations, boots-on-the-groundconservation, and contributions to our understandingof the ecology, life history, and evolutionary history of adiversity of organisms in the form of technical reports,
popular articles, books, and peer-reviewed papers.
Learn more at www.sazoo.org
and follow on 		@SanAntonioZoo
				

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CHIRON K9
Email: Paul@Chiron-K9.com
Program webpage: www.chiron-k9.com
Chiron K9 is a research-based training, coaching, and consulting company that is
the leader in integrating proven canine science and support into field-based projects.
The company’s focus is detection, especially in conservation and the environment,
and supporting scientific research. Based in Somerset, Texas, United States, they
study the disciplines of detection canines and integrate the proven science-based
research into applied practice. Chiron K9 has supported detection canine researchwith leading academia and Federal agencies.
Learn more at www.chiron-k9.com
and follow on 			
FB-@ChironK9LLC |YT-@ChironK9									 IG-@ChironK9LLCDALLAS ZOOEmail: info@DallasZoo.com
Program webpage: www.dallaszoo.com/protecting-the-twelve/texas-native-wildlife
The Dallas Zoo is dedicated to creating a better world
for animals. Named one of the nation’s Top 10 Zoos
by USA Today, it is the largest zoological experiencein Texas. The zoo has been accredited continuously
by the Association of Zoos & Aquariums since 1985,
and features a 106-acre park, thousands of animals,
and an education department that offers programs
for all ages. The zoo is located at 650 S. R.L. Thornton
Freeway (I-35 at Marsalis) and is open seven days aweek from 9 a.m. to 5 p.m.
Learn more at DallasZoo.com or call 469.554.7500.
and follow on 		@DallasZoo
				

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HORNED LIZARD CONSERVATION SOCIETY
Email: hornedlizardinfo@gmail.com
Program webpage: www.hornedlizards.org
The Horned Lizard Conservation Society (HLCS) is a 501(c)(3) non-profit organizationand is the only organization in the world dedicated to protecting horned lizards. In late1990, citizens concerned about the decline of the horned lizard from various states met
in Texas and discussed creating an organization that would help to conserve the horned
lizard. The HLCS became an officially formed organization in January 1991. The HLCS
has a Board of Directors that oversee the general operation of this organization and has
regional contacts. The HLCS offers grants for scientific research, education, and outreach
events regarding information on conservation of horned lizards. In addition to offeringresearch grants, some of the Society’s other activities include: educational presentations
at environmental and conservation events, organizing and leading horned lizard species
surveys on both private (with permission) and public lands, rescue, recovery andreintroduction of displaced specimens, and creation anddistribution of educational materials.
Learn more at www.hornedlizards.org
and follow on 			
FB-@hornedlizard | IG-@hornedlizardconservation									YT-@Hornedlizardconservationsociety

TCU HORNY TOAD PROJECT
Email: dean.williams@tcu.edu
Program webpage: www.deanwilliamslab.com
Our laboratory has been focused on understanding the genetic structure and ecologyof Texas horned lizards. We have mapped the genetic diversity of Texas horned lizards
across the state of Texas and in zoos to help inform reintroduction efforts. We havebeen studying the ecology of reintroduced lizards including diet, habitat usage, thermal
ecology, predation, and survival. We also have a long-term study of Texas horned
lizards living in the towns of Kenedy and Karnes City in south Texas to gain a better
understanding of how they have persisted in close association with people in thosetowns. The purchase of merchandise from the following website

https://www.redbubble.com/people/thlizard/shop
goes towards supporting our field research.
Learn more at http://www.hornedlizards.org/

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WORKS CITED
Allen, C., Epperson, D., & Garmestani, A. (2009). Red Imported Fire Ant Impacts on Wildlife:
A Decade of Research. The American Midland Naturalist.
https://www.researchgate.net/publication/232696563_Red_Imported_Fire_Ant_Impacts_on_
Wildlife_A_Decade_of_Research
Commans, P., Buchberger, G., Baumgartner, A., Kogler, R., Bauer, S., & Baumgartner, W. (2015,
August 6). Directional, passive liquid transport: the Texas Horned Lizard as a model for abiomimetic ‘liquid diode’. Journal of the Royal Society.
https://doi.org/10.1098/rsif.2015.0415
Dickman, C. (1987). Habitat Fragmentation and Vertebrate Species Richness in an Urban
Environment. The Journal of Applied Ecology.
https://www.researchgate.net/publication/243766309_Habitat_Fragmentation_and_Vertebrate_Species_Richness_in_an_Urban_Environment
Donaldson, W., Price, A., & Morse, J. (1994, May 1). The current status and future prospects of
the Texas Horned Lizard (Phrynosoma cornutum) in Texas. The Texas Journal of Science.
https://www.thefreelibrary.com/
The+current+status+and+future+prospects+of+the+Texas+horned+lizard...-a0128674069
Dropkin, A. (2015, June). Our Toad to Ruin. Texas Monthly.
https://www.texasmonthly.com/the-culture/our-toad-to-ruin/
Henke, S., & Fair, S. (n.d.). Management of Texas Horned Lizards. Texas A&M Kingsville.
https://webapps.fhsu.edu/ksherp/bibFiles/21634.pdf
Heuring, C., Barber, D., Rains, N., Erxleben, D., Martin, C., Williams, D., & McElroy, M. (2019).
Genetics, morphology and diet of introduced populations of the ant-eating Texas Horned
Lizard (Phrynosoma cornutum).
https://doi.org/10.1038/s41598-019-47856-4
Lantz, G. (2001, August 1). For the love of a horned lizard. National Wildlife Federation.
https://www.nwf.org/Magazines/National-Wildlife/2001/Texas-Horned-Lizard
Sherbrooke, W. (2017). Antipredator Nest Guarding by Female Horned Lizards ( Phrynosoma ):Iguanian Parental Care. Herpetologica.
https://www.researchgate.net/publication/320369151_Antipredator_Nest_Guarding_by_
Female_Horned_Lizards_Phrynosoma_Iguanian_Parental_Care
Sherbrooke, W., Middendorf, G., & Douglas, M. (2004). Responses of Kit Foxes (Vulpes
macrotis) to Antipredator Blood-Squirting and Blood of Texas Horned Lizards (Phrynosoma
cornutum).
https://www.researchgate.net/publication/250067738_Responses_of_Kit_Foxes_Vulpes_
macrotis_to_Antipredator_Blood-Squirting_and_Blood_of_Texas_Horned_Lizards_
Phrynosoma_cornutum
Texas Parks and Wildlife Department. (n.d.). Texas Horned Lizard Watch.
https://tpwd.texas.gov/huntwild/wild/wildlife_diversity/texas_nature_trackers/horned_lizard/

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Texas Parks and Wildlife Department. (n.d.). Texas Horned Lizard Watch
Management and Monitoring Packet.
https://tpwd.texas.gov/publications/pwdpubs/media/pwd_bk_
w7000_0038.pdf
Texas Parks and Wildlife Department. (2008). Texas Horned Lizard Watch
10-Year Summary Report: 1997-2006.
https://tpwd.texas.gov/publications/pwdpubs/media/pwd_rp_
w7000_1442.pdf
Williams, D., Rains, N., & Hale, A. (2019). Population genetic structureof Texas Horned Lizards: implications for reintroduction and captive
breeding.
https://doi.org/10.7717/peerj.7746
Wolf, A., Hellgren, E., Bogosian, V., & Moody, R. (2013). Effects ofHabitat Disturbance on Texas Horned Lizards: An Urban Case Study.
Herpetologica.
https://www.researchgate.net/publication/269580922_Effects_of_
Habitat_Disturbance_on_Texas_Horned_Lizards_An_Urban_Case_Study

PHOTO CREDITS
Page 2: A Texas horned lizard basking on a rock with a rocky background- 			
Shutterstock Id: 8371966 - Photographed by Rusty Dodson

https://www.shutterstock.com/image-photo/texas-horned-lizard-			basking-on-rock-8371966

Page 3: Single horned lizard (top of page)- Photographed by Kamryn Richard 			12 Texas horned lizards (right side of page) - Photographed by Caitlin Bailey
Page 5: The Horned Jack Lizard- Image credit: Flickr
Page 6: Range Map- Image credit: iNaturalist
Page 7: Fire Ant image- Image credit: USDA
Fire Ant mound image- Image credit: Terminix
Page 8: Harvester Ant images-Image credit: Wild Lens Collective
Page 9: Texas horned lizard in grass- Photographed by Brittany Nunn
Page 16: Texas Horned Lizard Scat- Photographed by Gary Nafis

http://www.californiaherps.com/noncal/southwest/
swlizards/images/pcornutumfeces810.jpg

Page 24: 12 Texas horned lizards (right side of page) - Photographed by Caitlin Bailey

All other photos not credited were taken by San Antonio Zoo conservation team,
Jacob Downing or from iNaturalist.

GUIDE DESIGN by Courtney Lubke

24

Texas Horned Lizard Advocacy Guide
Created By: San Antonio Zoo in partnership with Texan by Nature