Giant Freshwater Puffer

Tetraodon mbu

About This Animal

SIZE: Up to a maximum of 30 inches (75 cm)

RANGE: Widely distributed in the Republic of Congo, Democratic Republic of Congo, Tanzania, Zambia, Burundi and Cameroon

HABITAT: Inhabits rivers and lakes, including Lake Tanganyika

DIET: Mostly a molluscivore consuming different types of shellfish and snails

ON EXHIBIT: Rivers of the World Gallery in River Journey

The giant freshwater puffer, also known as the Mbu Puffer and the Giant Green Puffer, is a carnivorous fish that prefers to dine on crunchy foods such as mollusks and crustaceans to help prevent tooth overgrowth.  Like all of its relatives, it is capable of inflating itself with water or air when stressed or otherwise frightened.  Puffers also have a few other interesting adaptations.  

They are one of the few fish species in the world that can actually blink or close their eyes.  Their beak-like mouthparts which are used to crush shelled invertebrates are formed by the fusing of two teeth from each jaw.  Additionally, puffers have the ability to change their color depending on their mood or surroundings.    

Parts of the puffer’s body contain the deadly neurotoxin, tetrodoxin.  It cannot be passed on to humans unless it is eaten.  When ingested in sufficient quantities, it can cause paralysis and even death.  The toxin is over 1,000 times deadlier than cyanide and there is no known antitoxin for it today.  Puffer is one of the famous delicacies of the orient especially in Japan.  Even though it is prepared only by highly trained chefs, people have still died from eating it.

According to the IUCN Red List of Threatened Species, the giant freshwater puffer is considered of least concern.