|Porcupinefish (Diodon nicthemerus)
Photo by Mikkel Elbech
Porcupinefish are fish of the family Diodontidae, (order Tetraodontiformes), also commonly called blowfish (and, sometimes, "balloonfish" and "globefish"). They are sometimes collectively (but erroneously) called pufferfish.
Porcupinefish are medium to large sized fish, and are found in shallow temperate and tropical seas worldwide. A few species are found much further out from shore, wherein large shoals of thousands of individuals can occur. They are generally slow.
Porcupinefish have the ability to inflate their body by swallowing water or air, thereby becoming rounder. This increase in size (almost double vertically) reduces the range of potential predators to those with much bigger mouths. A second defense mechanism is provided by the sharp spines, which radiate outwards when the fish is inflated.
Some species are poisonous, having a tetrodotoxin in their internal organs, such as the ovaries and liver. This neurotoxin is at least 1200 times more potent than cyanide. The poison is produced by several types of bacteria that are obtained via the fish's diet. As a result of these three defenses, porcupinefish have few predators, although adults are sometimes preyed upon by sharks and orcas. Juveniles are also preyed on by tuna and dolphins.
Pop culture 
- The UNIX-derived computer operating system OpenBSD uses a porcupine fish as its mascot, named Puffy.
- A porcupinefish was used in the 2012 season of Australia's Big Brother. She was a talking animal with a Cockney accent, and sort of a second big brother, that also manipulated and gave tasks to the housemates.
- In the 2003 Disney/Pixar film Finding Nemo, the character Bloat (voiced by Brad Garrett) is a porcupinefish.
- In the 2004 DreamWorks Animation film Shark Tale, the character Mr. Sykes (voiced by Martin Scorsese) is a porcupinefish.
See also 
Media related to Diodontidae at Wikimedia Commons
- Mills, Dick (1993). Cooke, Jane, ed. Aquarium Fish. San Diego: Dorling Kindersley. p. 281. ISBN 1-56458-293-0.
- Keiichi, Matsura & Tyler, James C. (1998). Paxton, J.R. & Eschmeyer, W.N., ed. Encyclopedia of Fishes. San Diego: Academic Press. p. 231. ISBN 0-12-547665-5.
- Piper, Ross (2007), Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals, Greenwood Press.
- Balloonfish. Florida Museum of Natural History. Casey Patton. Accessed on June 24, 2005.
- Froese, Rainer, and Daniel Pauly, eds. (2006). "Diodontidae" in FishBase. May 2006 version.
- Froese, Rainer and Pauly, Daniel, eds. (2005). "Diodon holocanthus" in FishBase. May 2005 version.
- "Diodontidae". Integrated Taxonomic Information System. Retrieved 24 June 2005.