About 70% of the Texas horned lizard's diet is made up of harvester ants, though they supplement these with termites, beetles, and grasshoppers.
In recent years, the species has declined by about 30% of its range, though it may be making a comeback.
The decline is usually blamed on overuse of pesticides and the spread of nonnative, highly aggressive and fiercely territorial red imported fire ants.
Both eradicate harvester ant colonies, destroying the lizard's principal source of food.
The Texas horned lizard is now a protected species, and, in Texas, it is illegal to take, possess, transport or sell them without a special permit.

A University of Texas publication notes that horned lizard populations continue to disappear throughout the southwest despite protective legislation.
The Texas horned lizard has disappeared from almost half of its geographic range.
Population declines are attributed to loss of habitat, human eradication of the ant populations upon which the lizards prey, displacement of native ant populations by invading fire ants (aided by synergistic effects of native ant eradication), and predation by domestic dogs and cats.

In 2014, the Center for Biological Diversity in Tucson, Arizona petitioned the Oklahoma Department of Wildlife Conservation to have the Texas horned lizard put on the endangered species list due to the massive declines of its population in Oklahoma, where it was once plentiful.
The Center said it may later seek protection for the animal on a Federal level; it also said that reptiles in general are dying off at up to 10,000 times their historic extinction rate, greatly due to human influences.

In Texas, the creature has been declared threatened and a breeding and reintroduction program has been started by the Fort Worth Zoo.
Hatchlings are bred and released in targeted areas in the hope that with a large number of animals, enough will survive to grow the population in the wild.
Typically in such reptile reintroduction programs, less than one percent of a female's offspring will survive in the wild to adulthood.
About 70% of the Texas horned lizard's diet is made up of harvester ants, though they supplement these with termites, beetles, and grasshoppers. In recent years, the species has declined by about 30% of its range, though it may be making a comeback. The decline is usually blamed on overuse of pesticides and the spread of nonnative, highly aggressive and fiercely territorial red imported fire ants. Both eradicate harvester ant colonies, destroying the lizard's principal source of food. The Texas horned lizard is now a protected species, and, in Texas, it is illegal to take, possess, transport or sell them without a special permit.
A University of Texas publication notes that horned lizard populations continue to disappear throughout the southwest despite protective legislation. The Texas horned lizard has disappeared from almost half of its geographic range. Population declines are attributed to loss of habitat, human eradication of the ant populations upon which the lizards prey, displacement of native ant populations by invading fire ants (aided by synergistic effects of native ant eradication), and predation by domestic dogs and cats.
In 2014, the Center for Biological Diversity in Tucson, Arizona petitioned the Oklahoma Department of Wildlife Conservation to have the Texas horned lizard put on the endangered species list due to the massive declines of its population in Oklahoma, where it was once plentiful. The Center said it may later seek protection for the animal on a Federal level; it also said that reptiles in general are dying off at up to 10,000 times their historic extinction rate, greatly due to human influences.
In Texas, the creature has been declared threatened and a breeding and reintroduction program has been started by the Fort Worth Zoo. Hatchlings are bred and released in targeted areas in the hope that with a large number of animals, enough will survive to grow the population in the wild. Typically in such reptile reintroduction programs, less than one percent of a female's offspring will survive in the wild to adulthood.
Texas horned lizard