What is a Horned Lizard?
Horned lizards are called horny toads but really are not frogs or toads. They are reptiles - lizards. Like all reptiles, horned lizards depend primarily on their environment to control their body temperature - and they like it HOT! Most horned lizards live in desert or semi-arid environments. They are often seen basking in the morning sun on a summer day. Even so, they are susceptible to overheating, so as the day gets warmer, the lizards move into the shade and may even go into burrows to stay cool in the long summer afternoons.
Horned lizards have many characteristics which distinguish them from other lizards. The most obvious characteristic is their body shape. They lack the sleek, tubular body shape of most lizards. Instead, they have a wide, flattened form which is well adapted for camouflage and their burrowing habits. Horned lizards are noticeably spiny, with a crown of horns adorning the back of their heads and various spines on their bodies.
Horned lizards prefer to eat ants, but they will also eat many other types of invertebrates, such as grasshoppers, beetles and spiders, to supplement their diet. Usually, they search for prey in open areas, moving quietly searching or waiting for an unsuspecting ant or other food item to come into view. When a prey animal passes by, the lizard quickly snaps it up with a flick of its tongue and swallows it whole.
Horned lizards' foraging behavior puts them in danger of being eaten themselves. They are preyed upon by hawks, roadrunners, snakes, lizards, coyotes, ground squirrels, mice, cats and dogs. Horned lizards attempt to avoid predators by using various tactics, some of which are quite unique. Their most unusual tactic is the ability to squirt a stream of blood from the corner of their eyes. This stream may be directed with limited accuracy at the predator's eyes and mouth and is probably a last resort.
Another behavior horned lizards exhibit is the ability to inflate their bodies until they look like spiny balloons. However, they most effectively avoid predators by simply holding still. Horned lizards' color patterns closely match the soil on which they live and they can eliminate their shadows by flattening against the ground. If forced to move, a horned lizard runs only a short distance, stopping unexpectedly. The horned lizard lies flat, blending into its surroundings, and the predator is left chasing nothing.
Thirteen species of horned lizards are recognized in North America. They occur from southern Canada to Guatemala. Seven species reproduce by laying eggs (oviparous) and six species give birth to live young (viviparous). Horned lizards live in a variety of arid and semi-arid environments from oak-pine woodland to thorn scrub deserts.
Populations of the Texas Horned Lizard have disappeared in East and Central Texas, and are decreasing in North Texas as well. A decline and disappearance of them in Oklahoma and New Mexico has been noted. Other species of horned lizards throughout the Southwest are also in trouble including the San Diego Coast Horned Lizard and the Flat-tailed Horned Lizard. The primary cause for population decline is the loss of habitat by agricultural and urban conversion. Other causes also have lead to declining populations including overharvesting for the pet trade and curio trade and the invasion of exotic species, particularly exotic ants which the lizards can not survive on and outcompete their preferred ant.
In Texas, both the Texas and Mountain Short-horned lizards are state listed as Protected: which means it is illegal for anyone to take, possess, transport or sell them without a special permit. Not only is it illegal to keep horned lizards, but they are difficult to care for in captivity, and most captured ones eventually die from improper care.
Horned Lizards are wonderful, unique lizards that share our lives and heritage. Many of us played with them growing up because we could actually catch them - but we also let them go back to their home in the soil and sand. Our lives and childhoods are indebted to these lizards for allowing us to share with nature and learn from it. We hope they'll persist with us beyond the next millenium.