Why Do Toads Have Warts?

I had a pet toad as a kid and I wondered why it had warts. My grandmother told me it was to give me warts. I did not listen, thank goodness, and learned the true reason toads have warts as an adult. So here it is.

Toads use their wart-like bumps to camouflage with their environment and protect them from predators. The “warts” on a toad’s skin are actually glands that act as camouflage and secret poison. Toads can secrete different levels of toxicity depending on the species.

All toads have three types of glands, mucous, granular, and parotoid. The granular and parotoid glands are the ones that appear to look like warts. These glands play essential roles in the protection and overall well-being of toads. Read on to find out what these glands do.

What Are The Warts on Toads?

There are three types of glands on toads: mucous, granular, and parotoid.

Mucous glands help keep the toads’ skin hydrated and moist. Granular glands are the small bumps on a toad’s body that are often mistaken for warts. Toads also have two large glands on the sides of their heads behind their eyes called parotoid glands.

Although often confused as warts, the glands on a toad have nothing to do with an injury or infection. Instead, they are natural aspects of a toad’s skin that are used to ward off predators.  The mucous and granular glands cover a toad’s body. Granular glands tend to aggregate around a toad’s dorsolateral areas, head, and shoulders.

A toad’s skin may look like warty, but the glands on their bodies are not warts at all warts. Toads do not have warts and cannot give you warts.

Toads Have “Wart-Like” Glands to Fend Off Predators

The wart-like glands on toads are their defense mechanism against being eaten. Some toads are only slightly toxic, while others have the ability to take a human life. Simply avoid handling toads to avoid any poison.

All toads have “warts” which means that all toads have granular glands that secrete poison. However, how toxic a toad may depend on the species. For example, Cane Toads, which are invasive in Australia and Florida, are highly poisonous.

Depending on the species, a toad’s poison can attack multiple of an animal, human, or predator’s body and organs, making it dangerous and potentially lethal if ingested. Learn more about poisonous toads in this dedicated guide on our blog.

Toads Use Their Warts For Camouflage 

A toad’s glands do more than just secrete poison to ward off predators. It also helps prevent predators from finding the toad in the first place. 

The greenish, russet-brown colors of the toad combined with the lumps that the glands create on their back allow them to more easily blend into their surroundings. Toads live on land and an animal that is smooth against a complex background will stand out much more to predators than one with features that match its surroundings. 

This is especially true since toads prefer open habitats that do not provide much covering from birds that attack them from above. They use the camouflage combined with the poison to keep them safe.  

Are Toads Warts Dangerous?

Toad warts (or glands) are not dangerous if you do not interact with or touch the toad. However, if you ingest toad toxin, or if it enters your sinuses or bloodstream, it can be dangerous depending on the species and amount ingested.

Most toads cannot poison you through skin-to-skin contact. However, if you ingest their poison, it can result in sicknesses or death. So avoid touching toads or wear gloves if necessary. For example, I show how to safely save toads from a window well in this guide on our blog (CTNF).

And toads cannot give you warts

Not All Toads Have Parotoid Glands

All toads of the Bufonidae or “Bufo” family have parotoid glands. This family of toads is known as the “common toads.” However, this is just one of many families of toads. Not all toads from other families have parotoid glands.

Several other families contain toad species that do not have parotoid glands, including the families:

  • Discoglossidae
  • Pelobatidae
  • Rhinophrynidae
  • Scaphiopodidae

Toads with parotoid glands secrete a special kind of toxin known as bufotoxin. This toxin is known to contain:

  • Epinephrine
  • Dopamine
  • Serotonin
  • Indolealkylamines (similar to a hallucinogen) 

However, the ratio of toxins varies from toad to toad depending on size and species. That is why some toads are more poisonous than others.

More About Toad Warts

Learn more about toads and their warts in the following guides on our blog:

Common Questions About Toad Warts

What are the bumps on the back of a toad? The bumps on toads are glands including mucous, granular, and parotoid glands. Mucous glands keep the toads’ skin hydrated, granular glands help with camouflage and fending off predators, and parotoid glands secrete poison. The bumps on a toad’s back are not warts.

Why do toads have bumps on their backs? Toads have bumps on their backs to help them camouflage and defend themselves from predators. The parotoid glands behind a toad’s eyes can secrete a toxic poison that can help fend off predators that try to eat them.

Why are toads lumpy? Toads are lumpy because they have granular glands and parotoid glands on their bodies. These glands help with camouflage, fending off predators, and secreting poison.