Joel Rakower pleaded guilty Wednesday in federal court in Brooklyn, CNN reported.
In his plea, Rakower admitted to buying piranhas from a Hong Kong tropical fish supplier and importing the fish into New York City, said a Department of Justice statement.
Rakower said he instructed the supplier to label the fish as silver tetras, a common and unaggressive aquarium fish, because piranhas are illegal to own in New York City, the statement said.
In 2011 and 2012, Rakower smuggled 39,548 piranhas into the United States, the statement said.
Rakower was "driven by greed and without regard for the health and safety of people or the environment," said Queens District Attorney Richard Brown, who helped investigate the case.
Rakower agreed to pay more than $70,000 in fines and restitution. His company was also placed on two years of probation.