From a continent whose rivers are characterized by blind pink dolphins, electric eels, freshwater stingrays, and Lambada dancers, the pacú is hardly unusual. South America has much to offer to both the students of history and nature lovers. So, for people visiting from outside of the Americas, the pacú is yet another of its wonders.
The name ‘pacú’ actually covers several species and is applied incorrectly by aquarists in North America. In South America, pacú is the vernacular for small and medium-sized fishes of the Metynnis, Mylosomma, and Myleus genera. So, in countries such as Paraguay, Brazil, and Venezuela, the various species of what North Americans know as pacú are called ‘tambaqui’, ‘pirapitinga’, and other such names of Amerindian origin. A common species is Colossoma macropomum.
These fish are related to a much smaller fish known to aquarium hobbyists as ‘tetra’ and have a similar physiognomy, but on a much larger scale. Pacú are also related to their famed piranha cousins, which have also found a home in North American aquariums and not a few of its lakes and rivers. Pacú, or piripitinga or tambaqui are economically useful as food fish, being raised in South America – and Thailand as well – by fish farms. Pacú tolerate low-oxygen environments, such as fish ponds. They are omnivores. Besides eating things like snails, small mammals, fish eggs and such, the adults also eat fruit and nuts. Hence the eerie teeth that resemble those found in those other omnivores: human beings.
Pacú species can reach as much as 60 pounds and more than 36 inches in length. While they are known to be sold to unsuspecting hobby aquarists as ‘vegetarian’ piranhas, they will actually eat anything and their size is not limited to the capacity of a typical aquarium. In Scotland, just a few years ago, a toddler dangled his little fingers in a pacu’s aquarium and was rewarded with a bite that required surgery. In another case, a man in Texas was bitten on the nose by a ravenous pacú when it leapt out of its fish tank.
Again, like Asian carp and other exotic species, pacú have become a problem in places where they have been introduced outside of South America. In the United States, for instance, they are found in several southern states. In Texas, there are some jurisdictions that are offering a $100 bounty for dead pacú caught in lakes and streams there. They are also found as far north as Michigan and Maine, and out in California and Wyoming.
Certainly in California they will find a goodly amount of fruit and nuts to consume.