Pacu is a freshwater fish from South America. It is present in majority of the streams and rivers in Orinoco and Amazon river basis of Amazonia lowland. However, they are said to be found also further away in Papua New Guinea; they were presented here artificially to assist in the fishing sector in the neighborhood.
Pacu and piranha, which consumes meat are related. The two share similar subfamily Serrasalminae even though their food habits differ. The piranha species is carnivorous while pacu is omnivorious and is inclined to be vegetative.
The variation can be seen in their teeth formation. Piranha’s teeth are pointed and razor sharp; pacu’s teeth are straighter and more square and look strangely similar to the ones for humans.
Pacu utilizes its teeth mostly to chew fruits and nuts; however, at times they consume other invertebrates and fish also. Normally, they consume nuts and fruits that fall from Amazon trees and float. In some instances, they have been known to assault male swimmers’ testicles, confusing them for floating nuts.
They have been christened ‘ball-cutter’ following their castration of two fishermen in the locality of Papua New Guinea. Therefore, when the fish was sighted in Denmark and afterwards in Washington, Illinois and New Jersey last year in a few lakes, there was a bit of panic.