Invader Alert!

Imagine a small African clawed frog suddenly plucked from its home—a warm, quiet pool of water in the cooler regions near the Sahara Desert in Africa. After a long trip to the United States, it finds a new home in an aquarium with a warm pool of water in a classroom. Children feed it lots of strange, tasty insects. Then, the school year is over. The adult frog, now 4 1/2 inches long, is dumped near the shore in a fast-moving stream. Great blue herons with hungry looks fly overhead. A family of raccoons search the shore for something to eat. One of the young raccoons grabs for the frog, but it uses its muscular back legs with webbed, clawed toes to dive deeper into the stream. The water is much colder than any it has ever felt, but it swims deeper—away from the predators.

After a while, the frog comes up for a breath of air. A small tadpole swims by. The frog grabs it and shoves it into its mouth. And there are plenty of tadpoles and other insects to eat near the shore of this stream. The frog grabs a bug and eats it, too.

Not many captive animals released into a strange habitat are as lucky. Most get quickly eaten. Others slowly starve because they don’t know how to hunt for food. Others may die when winter comes. This may be a happy ending for this one frog, but it could be a sad story for the native animals that live in and around that stream.

African clawed frogs carry a fungus that can kill other amphibians. This fungus has caused mass die-offs of leopard frogs and tiger salamanders in other states where African clawed frogs have been released into the wild. In Australia, the fungus likely caused the extinction of two native frog species.

African clawed frogs also have huge appetites. They eat any creature they can shove into their mouths, including native frogs, toads, salamanders, fish and insects. They also can outcompete larger animals for food.

These exotic invaders are difficult to kill. They can survive near-freezing temperatures. Their skin secretes toxins that keep predators from eating them. Their skin also produces chemicals that prevent disease, so the frogs stay healthy.

The females can lay 2,000 eggs several times a year. Eggs hatch in one week, and tadpoles become froglets in about seven weeks. Adults can start laying eggs when they are 1 year old, and they can live for up to 15 years. It may not take long for this aggressive invader to change a habitat once they become established.

African clawed frogs first arrived in the United States more than 50 years ago. They are still used in scientific research and are popular pets. Over the years some escaped or were released from labs and by pet owners. Today, populations of these frogs have been found in California, Colorado, Florida, New Mexico, North Carolina, Virginia and Wisconsin.

You can help protect Missouri by not releasing exotic animals. If you have an African clawed frog or other non-native pet, never release it into the wild! Either keep the animal until it dies naturally or find it a new home with someone else.

How to Identify Clawed Frogs

Clawed frogs are easy to recognize because they are the only frogs with clawed toes. The African clawed frog is the largest member in this family. It has a flat body and a small head. It doesn’t have a tongue, teeth, eyelids or external ears.
The skin is blotchy olive green or brown. The underside is cream-colored. It can change shades to match or blend into its environment. Many pet stores also sell albino clawed frogs.
African clawed frogs have small front legs with four unwebbed fingers. The back legs have five long, webbed toes with claws on the three inner toes.
Females may grow up to 4 1/2 inches, while the smaller males only reach 2 1/2 inches.