Crab Eating Frog

Fejervarya cancrivora

Amphibian

Transcript:

Today on Animal Fact Files we’re discussing the crab eating frog. Unsurprisingly, crab eating frogs eat crabs. They don’t do this all the time, though. It really depends on where they live. Crab eating frogs live throughout southeastern Asia from the Philippines to India. They’ve also been introduced to Papua New Guinea and Guam. Like many aquatic frogs, crab eating frogs live in swamps. What sets them apart from all other frogs alive on earth, is that they can live in saltwater. Crab eating frogs are also known as mangrove frogs, because they live in mangroves; brackish frogs, because they live in brackish water; and saltwater frogs, because they can survive in this marine environment.

Now, to be clear, crab eating frogs aren’t the only frogs that are able to tolerate salty water. Other species such as the cane toad, the European green toad, and the African clawed frog can all handle varying levels of saltwater for a short amount of time. The crab eating frog, however, is the only known living amphibian that can consistently inhabitat saltwater. The way they do this is by making their body more salty than the water surrounding them.

An amphibian’s skin is permeable meaning molecules such as oxygen and carbon dioxide can pass through it. This is why it’s so important for water to be clean where amphibians live! If the water they enter is salty, then their body also becomes salty. For most of them, this quickly becomes a fatal situation because they have no way to rid their body of the excess salt. Crab eating frogs, however, have developed a special trick where they can store more salt than the surrounding water, so when they enter saltwater, the salt from that water doesn’t affect them! Because of this, they’re considered the only living marine amphibians!

The crab eating frogs that live in saltwater habitats tend to have a diet more rich in crustaceans, hence the common name. However, crab eating frogs that live in freshwater environments more frequently eat insects and worms, so the name isn’t entirely accurate! Cab eating frogs are likely eaten by birds, mammals, and reptiles, though there isn’t much information on their natural predators. Humans capture these frogs for frog legs since their hind legs are so chonky.

In size, crab eating frogs average about three and a half inches (9cm) in length with females appearing slightly larger. This is typical of most frogs as we discussed in our bullfrog episode. At breeding age, males develop darker spots around their throat and call to draw the attention of females. While we couldn’t get the call of the crab eating frog in particular, this is the call of a species from the same genus: [audio of call] The crab eating frog’s call is low pitched but has that same gurgling.

There’s little information on the life cycle of the crab eating frog. Like other frogs, they hatch from eggs as tadpoles that develop into adults. Their tadpoles are also able to live in saltwater. Estimates put them at surviving to about 5 years old in the wild if they can avoid predation.

For more facts on crab eating frogs, check out the links below. Give a thumbs up if you learned something new today. Thank you to our Patrons SpikeSpiegel93, Dad, and everyone else for their support of this channel! Thank you to these viewers for today’s request! And thank you for watching Animal Fact Files!