‘Flying’ and ‘frogs’ are not two words you often hear in the same sentence. It’s hard for me to picture a winged frog, probably because frogs are pretty awkward animals. But there are a number of ‘flying’ frogs, though like many animals that have ‘flying’ in their name, these frogs are gliders, not true fliers.
For simplicity’s sake I’m going to focus on one species for this post, though gliding flight has evolved in a number of unrelated frogs. Wallace’s flying frog is thought to be the first flying frog discovered, by the the famous naturalist Alfred Russel Wallace (after whom the frog is named).
Wallace’s flying frog is found in tropical rainforests in Malaysia, Indonesia, Myanmar and Thailand. It’s hard to know the exact range of Wallace’s flying frog, as there are a number of similar species that occur in the same area. I also imagine it’s not always easy to find frogs in a rainforest, though I’ve never tried, so I can’t say for sure.
One of the reasons it might be hard to find flying frogs is their colour and size. They are big for flying frogs, but that only means about eight to ten centimetres. They also blend in pretty well with their surroundings, with bright green colouration on top, and a white belly. And because they spend most of their time high in trees, you can imagine how difficult it might be to find small, leaf coloured frogs in the canopy of a rainforest.
The most notable features of Wallace’s flying frogs are their webbed feet. They have very large feet, with yellow and black webbing that reaches all the way to the toes. Flying frogs also have a small flap of skin between their limbs, which help a lot with their gliding capabilities.
Since they are expert gliders, Wallace’s flying frogs spend almost all their time in trees. After all, if you can only glide and not fly, you need to get to a high place to glide from. When flying frogs feel threatened, they leap off whatever perch they’re on, and simply glide through the air until they find a safe landing spot. Thanks to their huge feet and webbing, flying frogs can glide over 50 feet.
One of the trickiest parts of gliding or flight is the landing, but Wallace’s flying frogs have a solution for that too. They have large toe pads at the end of each finger, which allow them to cushion the landing and stick to vertical surfaces with ease. It’s not just the toe pads that are special either — the frogs have cool bones in their feet that help press the pads against surfaces, creating the suction needed to grip the surface.
Mating in Wallace’s flying frogs is not the most exciting affair. Female frogs secrete a fluid which they churn into a frothy foam. She then lays her eggs in the foam, after which the male fertilizes the eggs. It’s very important that the parents construct the foam nest over water, otherwise when the eggs hatch, they will fall onto dry ground and die due to lack of moisture.
Although they can’t actually fly, I think flying frogs do their best, and should be appreciated for trying. After all, it’s no easy feat to be able to glide for over 50 feet, and then stick (quite literally) the landing. I know I certainly couldn’t, even with specialized equipment!
Cover image by Rushenb, CC BY-SA 4.0, via Wikimedia Commons