What to Know About Poisonous Frogs

Medically Reviewed by Nayana Ambardekar, MD on June 05, 2024
5 min read

Frogs are amphibians, or animals that can live in water and on land. They are usually not poisonous, unlike toads. But some frogs can be poisonous. 

Here’s all you need to know about poisonous frogs and how to tell if a frog is poisonous. 

Poisonous frogs produce and store alkaloid poisons or toxins in their skin, which makes them harmful to touch. They are commonly called poison arrow frogs or poison dart frogs. This is because Native American tribes rubbed their arrows or blowgun darts on the backs of poisonous frogs before hunting. 

Poisonous frog species belong to the family Dendrobatidae. Most of them are toxic, but only some are deadly. When a predator eats a poisonous frog, the toxins cause reactions like swelling, nausea, and muscle paralysis. They can also cause death in some. A tiny drop of frog poison can kill birds and small animals. 

These amphibians are social animals and often stay together in pairs or small groups. Male poisonous frogs wrestle with each other to claim territories. Females fight for the best sites to lay eggs. Couples nudge and caress each other, and their courtship period can last for many hours. They lay their clutch, which is a group of one to 40 eggs on average, in a dark, humid place like the base of a leaf or a hole in a tree. 

The male frog fertilizes the clutch. Within 10 to 18 days, the eggs grow into tadpoles. The frogs carry their tadpoles on their back into a stream or pool of water. After a few months, the tadpoles undergo metamorphosis and transform into adult poisonous frogs. Poisonous frogs can live for over 10 years, while some species like the phantasmal poison frog can live for 12 to 20 years.

Poisonous frogs are generally small. They’re around 0.75 to 1.5 inches or 20 to 40 millimeters in length. These frogs have beautiful bright colors and patterns on them. They come in various color combinations. Because of their eye-catching colors, poisonous frogs are known as “jewels of the rainforest.” Research suggests that these colors and patterns act as warning signs for predators. 

If a predator survives after eating a poisonous frog, it remembers the bad taste and associates it with the warning colors. It learns from its experience and avoids eating similar-looking frogs in the future. This allows the entire population of frogs with those colors to survive and not be eaten. Only one type of snake called Leimadophis epinephelus is unaffected by poisonous frogs and feeds on them.

Poisonous frogs are tiny land animals or terrestrial animals that are active during the day. Typically, they live in leaf litter or fallen leaves on the forest floor near streams or ponds. But some may live high up in the forest trees.

Geographically, they are found in the warm, tropical rainforests of Central and South America. They feed on small insects that they catch with their sticky tongues. 

Researchers have discovered about 220 species of poisonous frogs so far. Here are some commonly known types of poisonous frogs:

1. Green and black poison frog or Dendrobates auratus. This is a poisonous frog with green and black markings on its head and body. It is 1 to 2 inches in length. It's found in rainforests in Central America, from Nicaragua to Colombia. 

2. Black-legged poison frog or Phyllobates bicolor. This is a bright yellow frog with greenish or blackish limbs. It is native to tropical rainforests in Colombia and is 1 to 1.75 inches in size.

3. Dyeing poison dart frog or Dendrobates tinctoriusThis is a poisonous frog that comes in bright yellow, white, and sapphire blue colors and typically has black spots or patterns on its body. These frogs grow to 2 inches and are found in the lowland forests of Guyana and Brazil.

4. Blue poison frog or Dendrobates tinctorius "azureus." This amphibian is a morph or different form of Dendrobates tinctorius. It has brilliant blue skin, black spots on its head and body, and dark blue limbs. It is 1 to 1.75 inches and is found in the forests of northern South America.

5. Bumble bee frog, yellow-banded poison frog, or Dendrobates leucomelas. This poisonous frog has vivid yellow bands on a black body and is 1 to 1.5 inches in size. It is native to the forests of Venezuela and Guyana.

6. Phantasmal poison frog, tricolored frog, or Epipedobates tricolorThis little frog is less than 1 inch in size. It can be bright red, dark red, or brown with white and yellow stripes on its body. It is found in the wetlands of Ecuador.

7. Strawberry poison dart frog or Oophaga pumilioThis frog is about 17 to 24 millimeters in size. It has a strawberry red color that merges into shades of blue, black, white, green, yellow, or orange. These frogs are found in the tropical rainforests of Nicaragua, Panama, and Costa Rica.

8. Golden poison frog or Phyllobates terribilis. This frog is approximately 2 inches long. It has a radiant yellow color and large dark eyes. It is typically found in the tropical rainforests of Colombia.

Poisonous frogs have distinct, vibrant colors and patterns that separate them from other frogs. It’s best to avoid touching brightly colored frogs.

Some nontoxic or less poisonous frog species, like the mimic poison frog or Ranitomeya imitator, can imitate poisonous frogs. They have slowly evolved to look like poisonous frogs, with brilliant colors and patterns on them. Predators often confuse them for poisonous frogs and avoid eating them. This helps them survive in forests. However, a trained eye can distinguish mimic poison frogs from poisonous frogs based on their colors and patterns.

Poisonous frogs can also be confused with mantellas, which are less poisonous small, bright-colored frogs found in Madagascar.

The golden poison frog or Phyllobates terribilis is not just the most poisonous frog but the deadliest animal in the world. Just touching it can be toxic and dangerous. It produces toxins that can kill up to 20,000 mice or 10 humans at once.

The golden poison frog produces an alkaloid toxin called batrachotoxin. Scientists are studying the use of this toxin to create muscle relaxants, heart medicine, and anesthesia.

Many species of poisonous frogs are becoming endangered. They are very sensitive to even the slightest of environmental changes. Their populations are threatened by deforestation, climate change, and the loss of their natural habitat. They are also at risk of developing diseases like fungal infections. Many species are also smuggled and collected as exotic pets because of their spectacular colors and patterns. 

These little jewels of the rainforest need rescuing and conservation to prevent their species from disappearing and affecting Earth’s natural ecology.