It was supposed to be just another day of fishing for Ron Rossi and his family, until they scooped up a rare catch.

The Rossis were out at the Swedes Lake in New Jersey when they chanced upon a Pacu. Nobody recognized what it was but they thought it could have been a piranha given how the fish looked. The family did some searching on the internet and that's how they found out that they have caught an Amazon native.

They were in the right direction too: the Pacu is related to the piranha. They differ in that piranhas are carnivores while Pacus are omnivores. The two also have different sets of teeth. Where the piranha is known for its jagged, sharp teeth, Pacus have teeth that are more flat. In fact, when the Rossis pulled back the fish's bottom lip, they saw a set highly similar to that of a human's.

"It's exactly what it looked like on the Internet," said Ron.

But what's an Amazon native doing in New Jersey? It's a long way, after all, from its freshwater home in South America to a man-made lake in the state.

According to wildlife officials, the Pacu the Rossis captured could have been one bought by someone from a pet store for their aquarium. Unfortunately, many pet owners end up releasing their fish into the lakes.

The Department of Environmental Protection warned that fish like the Pacu can't survive in colder water. As such, if a fish must be disposed of, it must not be released into the wild but instead humanely destroyed.

That's what exactly the Rossis are planning on doing but they are concerned that there could be more Pacus in the lake. It rarely happens but the fish has been reported to attack people. Stories about Pacu attacks range from nibbling on toes and fingers of swimmers to exaggerations like the fish has an affinity for taking a bite out of the testicles of males in the water.

Wildlife officials are more concerned that the Pacu population will be competing with local species for food and that they can introduce exotic diseases and parasites that have the potential to wipe out native fish.

Last year, a Pacu was caught as well in Michigan. It weighed about 15 pounds and was two feet in length.

Photo: Ryan Somma | Flickr