A Puffer fish can puff up two to three times its size. The reason why they puff up is because it is their defense mechanism when they feel threatened. When they puff up, they double or triple from their original size – they are usually covered in spines which make it more difficult for predators to attack and eat them.
There are different species of puffers such as Amblyrhnchotes, Arothron, Auriglobus, Chelonodon, Colomesus, Ephippion, Javichthys, Leiodon, Marilyana, Monotrete, Reicheltia, Takifugu and Tylerius. Puffer fish are also known as puffers, blowfish, balloonfish, blowies, swellfish, globefish, toadfish, sugar toads and sea squab. They can grow up to 35 inches or 3 inches in length and they can weigh between 20 to 30 pounds.