Glass Frog

Family Centrolenidae

Amphibian

Transcript:

Today on Animal Fact Files we’re talking about glass frogs. Glass frogs could be called crystals of the rainforest. Not only do they look like little gemstones with their bright, translucent colors, they also have a crystal clear call. Glass frogs got their name because many of them have window-like undersides that give a clear view of their internal organs - in some species, an observer can even watch a glass frog’s heart beat.

Glass frogs live in Mexico and South America; they are considered arboreal creatures, meaning they spend a lot of their time in trees. Many species are only known from their breeding season because they’ll spend the rest of the year out of reach in the tree canopy. The breeding season for glass frogs typically falls sometime between March and November. This is considered the rainy season and is the best time for these frogs to get busy making babies.

As the rains begin, male glass frogs will descend to the forest understory, positioning themselves in spots on foliage along the edges of rivers, creeks, and streams. Sometimes the males will have to fight one another for the best locations and some species come equipped with weapons to do so. They’ll try to push each other off of leaves. Glass frogs aren’t that big. Just about every species maxes out at about an inch (2.54 centimeters) in length - though there is one oddball that can reach three inches (7.62 centimeters). The idea of one inch frogs trying to push each other off of leaves is both silly and adorable to me, though I’m sure it’s quite perilous for the losers.

Once settled in a prime spot, the males will make calls to the females. If a female is interested in a specific caller, she’ll make her way towards him and they’ll mate. The female will release a mass of anywhere from ten to 50 eggs on the vegetation and the male will fertilize them. Glass frog eggs are often positioned over a body of water so that when they tadpoles are ready to hatch they’ll slide off into the water below. Many glass frog species protect their egg clutches. Mostly males have been observed performing this behavior, but females have been seen participating in egg protection, as well.

The parents may swat away unwanted intruders such as flies and wasps. They’ll also consume eggs that have been damaged or may contain a parasite so as to prevent anything spreading to the rest of the clutch. Glass frogs are the most vulnerable as eggs, with predators including spiders, snakes, crabs, crickets, and other arthropods, so their parental protection is valuable.

It takes anywhere from eight to twenty days for the eggs to hatch. Usually the tadpoles will emerge during a heavy rain. This will stir up the sediment of the water below which will help camouflaged the babies as they enter their new watery world. Glass frog tadpoles stick to the bottom of the water column, usually hiding under sediment or debris, and their mouths are designed to help them cling to objects like rocks littering the water’s floor. It can take months to up to two years for the tadpoles to fully metamorphose into adults, but there is conjecture glass frogs may live to be more than five years old!

Glass frogs eat small arthropods, and may eat algae as tadpoles, though this hasn’t been observed in the wild. Unlike many frog species, glass frogs have forward facing eyes. They also have green bones. Because they’re somewhat see-through and they come in colors to help them blend in with their surroundings, any other color might just stand out. So their bones are green.

Currently there are somewhere around 150 described glass frog species, but there’s still a lot of research to be done involving these little froggos, so this number is likely to change as more information becomes available.

For more facts on glass frogs, check out the links in the description. Give a thumbs up if you learned something new today, and thank you for watching Animal Fact Files.