A full-scale search of all lakes and waterways in the Dnepropetrovsk region of the Ukraine is underway for the invasive Piranhas. The piranhas are already responsible for killing off large portions of fish, muskrats, ducks and snakes. Even a few fishermen have fallen victim to these vicious carnivores, though none have died yet.
It is thought that the lax government control over the pet industry, the low cost of pet piranhas (under $10 each), and unwilling owners dumping their fish into the local water systems. Even those willing to take on the responsibility of them as pets may not understand the risk. Like if your mom decided to clean your tank and ended up loosing two fingers and getting rabies. Once free, the piranhas quickly take over as they have many advantages over the local species, breeding easily and constantly consuming.