When do blowfish puff up

Narrator: If there's one thing you know about puffer fish, it's that they can do this. When aggravated by a predator, they, you know, puff up. Some puffers, like the porcupine fish, become a bona fide spike ball, moving through the water seemingly out of control.

But if you peer inside a puffer, you'll learn that puffing up isn't the only trait that makes these fish one of the most threatening creatures in the sea. Contrary to what it looks like, puffer fish are not like balloons.

Because what's normally inside them isn't air. It's water. Elizabeth Brainerd: What they do is they actually take water into their mouths in a big mouthful of water, and then they pump it down into their stomach. Brainerd: And they do that anywhere 10 or 15 times, pump, pump, pump, pump, pump, pump, until they inflate completely, and then they hold it and they'll just be a big, spiny ball.

Narrator: And as you might expect, this requires some pretty sophisticated biology, starting with the stomach. It's made of dozens of tiny folds, kind of like an accordion.

These folds are important because when the stomach fills up with water, it can expand without rupturing. And puffer fish expand a lot. They sometimes have difficulties expelling this from their stomach, so take extra care when catching them. Features Post The World's forgotten fishes 16 August Features Post How to set up a low maintenance aquascape at home 04 August Follow the puffer with the net, continuing to tap it.

This will eventually either scare or anger the fish into puffing up. It may not puff up all the way at first so you may need to tap it again. By using the site, you agree to the uses of cookies and other technology as outlined in our Policy, and to our Terms of Use.

Tap the puffer with the handle of the net. Funny Fill-In. Amazing Animals. Weird But True! Party Animals. Try This! Explore More. Common Name: Pufferfish.