I’m sure everyone has heard of poison dart frogs, but do they really know anything about them? I certainly didn’t, so I did some quick research, and decided to make a blog post about them (you might have guessed by now that a significant portion of my time is spent looking up animals online). Here’s what I knew before I looked them up: 1) they are colourful and pretty. Probably the prettiest amphibians out there, if you ask me. 2) they are poisonous.
It turns out, there isn’t just one type of poison dart frog; there are over a hundred species, all members of the family Dendrobatidae. They inhabit tropical rainforests in Central and South America, enjoying the lovely wet weather that frogs love so much. Most species live on the ground, although some spend most of their time in the tree canopy, climbing up to ten metres high. I’m scared of heights over three metres, so I can’t imagine what ten metres must look like to a tiny little frog. Just the thought of it makes me shudder.
And poison frogs are tiny – the biggest species only reach six centimetres while most are only about two centimetres from end to end. Despite their minuscule size, poison dart frogs wander about nonchalantly in broad daylight, scoffing at every would-be predator that ambles by. This is where those two facts I knew about these frogs come into play. Because of course the poison frog is poisonous. Any animal that eats it is in for a nasty experience. Some frogs are so poisonous that they can easily kill a human, and the most toxic species contains enough venom to kill ten grown men. The aesthetically pleasing colours that are characteristic of poison dart frogs are basically a blatant message: “Eat me and you’ll get sick.”
Luckily for pet frog owners, poison dart frogs rely on their diet to get the compounds needed to make their poison. The frogs eat ants, termites and beetles, which contain the toxins in the frog’s poison. If a poison dart frog is removed from its habitat and fed an insect-free diet, it fails to produce poison. The frogs never lose their ability to be toxic, though – give them their natural diet and they get nice and deadly again.
Poison dart frogs are very territorial, fighting over bits of water or the choice branches from which to call to females. Females and males will both defend territory, often in a position that looks like copulation. Trust me, it’s not. Poison frogs fertilize their eggs externally, meaning the females lays a clutch of eggs and the male then deposits his sperm onto them. No male-female contact required. Still, females do choose their mates, picking males with the brightest colours and best calling branches. Some females even sneak into other frogs’ nests and eat their eggs.
After any surviving eggs hatch, the parents carry the tadpoles to nearby water. Some species take the babies one by one on their backs, where the tadpoles stick to the parent’s skin. One interesting behaviour some poison frog species perform is carrying each tadpole into separate pools of water. The pools are usually high in the trees, and are formed in plant leaves. Every tadpole gets its own tiny pool, and the mother frog deposits an unfertilized egg into the pools to provide her young with a source of food. A bit too much work in my opinion, but I suppose the frogs don’t mind.
So that’s all I have to say about some of the coolest frogs on the planet. I would just like to mention that this post marks the one year anniversary of this blog, something I’m fairly excited about. So thanks to all my faithful (and unfaithful) readers that have kept me going and posting twice a week for a whole year! Hopefully I keep posting, and you keep reading!
Image By Heribert Dezeo – Own work, CC BY-SA 3.0