Fish They Explained Clearly

Steven Fills fish survey continues. They've already found huge piranhas. Now, with the help of local fishermen, they're hoping for a far more impressive catch. Okay. No, no, no, no, no. All right, this is big fish. Big? Big. WOW, LOOK AT THE SIZE OF THAT. IT'S A BIG ONE. YES, YES, YES, SURE. YEAH. [snorts] THAT IS A OH, THAT'S UNBELIEVABLE. is the banana catfish. Surveying fish is not easy. [snorts] They must identify each species and return them to the water as quickly as possible.

You can tell it's called the banana catfish cuz it's yellow on the belly, like a banana. And probably a good sort of 20 years old, would you say, Phil? Could be older. These fish can live a long time. Now, this fish is just covered in parasites. It won't pop out. Don't lose it. Oh, we've got another one. We've got another one, Phil. Okay, keep him. Where is it? Just down there, look. Another one there, look. It's actually scattering blood everywhere. It's like a full leech.

Look at that. Okay. Let's put our friend here back in cuz he's absolutely wonderful and we wouldn't want to harm him. So, old fella, off you go. Absolutely fantastic. Excellent. Absolutely nothing like as exciting as what we've got in here. The parasitic fish Steve's collected are known as vampire catfish or candiru. Apparently, if you stand in the water in these areas and you go to the toilet, will swim up the stream of urine and right inside you and lodge inside you using two backward-facing spines. These candiru actually swim in, latch into the

gills of a large fish, and drink the blood. You can see this one here which dropped out of the gills is absolutely thick full of blood. The big lesson, I guess, is if you're in the river, don't go for a wee. Steve's discovered what rules the depths by day. Now he wants to learn what hunts by night. Oh my god. These are called saber-tooth characins. They're saber-tooth tetras. It's the nearest-looking thing to an actual monster I've ever seen. It certainly deserves its saber-tooth name. That is incredible.

These teeth are so long, they need special sockets in their skull to accommodate them. Otherwise, they would just pierce their brains. Oh god. Okay. This is a top predator. They're extremely fast. They swarm around. They come up below fish and just spear them and just kill them instantly. Just like that. They just spear them. The fish are immobilized and then they eat them. I've got my fingers disturbingly close to those teeth, actually. I would imagine that those would just go straight through to the bone, wouldn't they?

Oh, they'd go right through your hand. Oh, no doubt about it. They're very strong. He's got to go back. Um I just wish I could see if I can put him in without losing my hand. Yeah, right. Yeah. Careful. Now we're seeing the night shift. Big catfish and saber-tooths. By day, the piranhas rule the rivers. You're never safe.