Poison Dart Frog

I am back in the beautiful rainforest on Barro Colorado Island, in the middle of Lake Gatun, in the Panama Canal.  Go to google maps and search for “Panama Canal, Panama”.  Find Barro Colorado Island in the middle of Lake Gatun.  Zoom way in (in the Satellite view) and you will see the only buildings on the island are in a cove along the eastern shore.  That is where I am living for the next 2 weeks.  Now, zoom out and notice that the rest of the island is all green, lush, beautiful tropical rainforest.  Scientists from all over the world come to this island to study all kinds of plants and animals. 

Even though we are in the middle of the dry season, here, in February, there are still some streams and wet areas.  That is exactly where I saw this poison dart frog this morning as I was hiking near a small stream. Frogs are amphibians and have thin skin that needs to be kept moist.  So, if you are looking for frogs, look near a stream.

Many frogs have camouflage coloration, making it difficult to see them in their environment because they blend in well.  Take a look at the pretty coloration of this little frog, who is only about the size of a nickel.  This frog produces toxins (poisons) in its skin.  Its bright coloration warns predators that this frog will not make a tasty meal (this is called aposematic coloration and is the opposite of camouflage).

Poison dart frogs got their names because there are a few species whose skin is very toxic and natives rubbed the tips of their blow darts on the frog’s skin to help them catch their dinner out in the forest.

I know there are other colors of poison dart frogs, but so far this is the only color that I have seen on BCI.

- Fran Zakutansky

Frog on a Raft

Frog on a raft

I was out walking in the rainforest and came up to a shallow pond.  As I looked carefully in the pond, I saw thousands of cute little tadpoles swimming around.  As I walked around the pond, I saw the coolest thing.  It looked like a white foam raft about the size of the palm of my hand and sitting pretty on top of the raft was a very small, but adorable frog.  Take a look at the photo.  The frogs make this foam raft by kicking their feet in the water as they release a liquid.  The mother (female) frog lays her eggs into the middle of the raft.

The floating raft is a good adaptation to protect the eggs from hungry predators, prevents them from dehydrating, and protects them from parasites and bacteria.  It’s convenient that the eggs hatch into tadpoles right in the water where the tadpoles swim.  After the tadpoles hatch, the foam disintegrates (it is biodegradable).  After a few weeks, the tadpoles start growing legs and lose their tails and become adult frogs and they look like the frog in the photo perching on top of the foam.

- Fran Zakutansky