The pirarucu is the largest species of freshwater fish in the world, found in the Amazon River basin and its tributaries. This fish has unique adaptations including a bony tongue plate and glossopharyngeal teeth that allow it to crush and swallow hard-shelled prey like catfish. The pirarucu can breathe through both gills and by gulping air into its swim bladder, enabling it to survive in waters with low oxygen levels by surfacing approximately every 15 minutes. Male pirarucu display brilliant red scales while females are wider to accommodate eggs. Conservation scientists study these fish to gather biological data on their physical reactions to the environment, including nutrition and habitat conditions, as the species is close to extinction.
Deep Dive
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Deep Dive
Monster, Amazon FishAdded:
the gigantic pirarucu.
I think I just sprained my ankle.
Welcome to Brazil. Can you believe it?
We're here.
We're actually exploring the Amazon [music] basin. Now, we have not reached the mighty Amazon River yet, but we're well on our way. We're on one of the tributaries, one of the over thousand tributaries that feed their way into this great river. First, I'm going to connect with a colleague of mine named Alex. He's a biologist with the University of Manaus, and he's studying an endangered animal. And in the Amazon, where there's water, there's usually fish. Some of them huge. For example, the gigantic pirarucu.
Be careful. Be careful.
I've learned when you hold the net, you hold it like that.
I think I just sprained my ankle.
This spicy fish is called the pirarucu, the largest species of freshwater fish in the world. Alex and his team need to frequently capture these aquatic giants to gather biological information, which helps determine how the fish are physically reacting to their environment. This data helps indicate things like if they're getting enough nutrition. Now, earlier, Alex and I caught a smaller pirarucu, and I got to see something really cool.
Try to open this mouth. Why? Is it going to bite me? No, but show the tongue.
It's got It's got a huge tongue.
>> You see the tongue?
>> tongue, like a bony plate. A bony plate, and does it have glosso-pharyngeal teeth in the back? So, it takes something in, smashes it with that tongue, then macerates it with the glosso-pharyngeal glossopharyngeal teeth. And what it likes to eat is creatures with hard heads just like this. It eats catfish.
Now with this one, we'll be lucky just to get it out of the water, never mind hold on to it.
This is the male. This is the male.
Look at the size of this.
You know what you need to recommend when you have another biologist come out and help you? Bring shorts, shirt to get wet, and bring a cup.
>> All right. You know what a cup is?
An athletic cup? No, a cup.
Look at the size of this guy. Amazing.
You can tell from watching us that was a battle.
That that guy feels good right in the foot, huh? I wonder how you get hit in the face. In the tongue.
>> Yeah.
Look at this.
Yeah.
Got a nice bruise coming in there.
Now you're probably thinking that this is stressful for this animal. Yes, stress is involved, but if you were going to pick a fish and take it out of the water, this is one of the best fishes to work with because it is a fish that's not only equipped to breathe with its gills, but by taking air into its mouth into its swim bladder as well. So it can survive in waters with low oxygen levels, coming to the surface like every 15 minutes taking a gulp there. It's amazing. You see how red it Look at that. How red is. Females are have red scales but not as brilliant as this.
>> brilliant and as as the red as strong as this one. Right. And the female would be wider. That's right. [snorts] >> She needs room in her cavity to support eggs and stuff like that. This is Jorge.
Jorge is a biologist. He's a geneticist.
Jorge, what kind of sample you taking?
Um just taking >> Flesh? No, no. Just a little bit of the skin? Yeah. No blood? No blood. Just skin. See, he doesn't need blood to get a good sample of genetic information because genes is in your fingernails, your blood, your flesh. So, you got to study here of behavior and genetics working together in a partnership to secure the species and you couldn't work hard enough because it's this close to extinction. So, we should get him in the pond, right?
Ready? Watch this. Here he goes. There he goes.
Woah.
Look at that.
Thanks a lot. Okay. Thanks, guys.
>> You got to You got to How do you say douche shower? A shower? Yeah. Douche or A ducha? Ducha. I'm going to go take a shower. All right. See you later. See you later.
>> [music]
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