Horned lizards, often mistakenly called “horned toads” due to their flattened bodies, are reptiles native to North America. Many people wonder if these creatures are poisonous. Despite their spiky appearance and unusual defense mechanisms, horned lizards are not poisonous to humans or pets. Their defenses deter predators, not inflict harm through toxins.
What Are Horned Lizards?
Horned lizards belong to the genus Phrynosoma and are lizards, not amphibians like true toads. Their common names reflect their distinctive appearance: a flattened, oval-shaped body and a crown of bony horns on their heads. These reptiles typically exhibit coloration that blends seamlessly with their environment, ranging from shades of tan and brown to reddish hues. They inhabit arid and semi-arid regions across North America, from southern Canada to Mexico.
Their diet primarily consists of ants, particularly harvester ants. Horned lizards often wait motionlessly near ant trails, capturing prey with a quick flick of their sticky tongue. This diet plays a role in their defense strategies.
How Horned Lizards Defend Themselves
Horned lizards employ a variety of non-poisonous strategies to protect themselves from predators. Their primary defense is effective camouflage, allowing them to blend into sandy or rocky environments. When threatened, they often remain motionless, relying on their natural coloration and flattened bodies to avoid detection.
If camouflage fails, their physical attributes deter predators. Sharp, spiny scales and prominent horns make them difficult to swallow. Some species also inflate their bodies with air, appearing larger and more cumbersome to attackers, which further discourages predators.
One remarkable defense is the ability to squirt blood from their eyes, a process known as autohaemorrhaging. This occurs by restricting blood flow from the head, which increases blood pressure and causes tiny vessels around the eyelids to rupture. The blood can be aimed with precision, sometimes reaching distances of up to five feet. This blood contains chemical compounds, including formic acid derived from their ant diet, which makes it foul-tasting and irritating, particularly to canine and feline predators.
Are They a Threat to People or Pets?
Horned lizards pose no threat to humans. They are docile creatures that typically do not bite defensively. While their spines might cause a minor prick, they do not inject venom or poison.
For pets, particularly dogs and cats, the horned lizard’s defenses are primarily deterrents. While a curious pet might be startled by their spiny texture or blood-squirting, the blood is not poisonous. The foul taste of the blood, due to the formic acid, is enough to discourage further interaction, but it will not cause toxic effects in pets. Many species of horned lizards are protected by law in various areas, making it illegal to capture or keep them as pets. Observing these reptiles from a distance is encouraged to ensure their safety and well-being.