An Arizona fisherman had an unexpected catch of the day this month when he reeled in a fish with human-like teeth.
Jeff Evans, who was fishing on the north side of Tucson's Silverbell Lake on Jan. 12, told the Arizona Daily Star that the fish even tried to bite him a few times.
The creature was later identified as a pacu fish, native to South America and a relative of the piranha, according to the Arizona Game and Fish Department in Tucson.
Game and Fish doesn't stock waterways with pacu fish, according to spokesman Mark Hart. The ones that show up in community waters start out as pets that people dump into lakes once they get too big to manage, he said.
Hart said people dumping in Tucson waters is an ongoing problem.
"What they don't realize is that invasive species crowd out native species," he said. "It's a bad practice, and people don't want to destroy something that's been a pet. But it's not helpful and can lead to some confusion."
Kevin Airola, who works at the Ocean Floor aquarium and tropical-fish store in Phoenix, said they typically have no more than five pacu fish in stock at any given time.
The allure of the pacu fish is that it looks so similar to a piranha, Airola said, but its adult size can make it a less-than-ideal pet: The pacu can grow up to 2 feet long.
"We do the best we can with explaining to people the size. One of the negatives of owning a pacu is they get quite large," he said, adding that those kept in aquariums can also be predatory, snacking on worms and small fish. Pacu mostly eat plants.
Don Mitchell, Arizona Game and Fish regional aquatic wildlife program supervisor, said pacu fish are actually on Arizona's restricted wildlife list of animals that cannot be owned without a permit.
Mitchell said one problem is that people buy pacu fish without permits and, oftentimes, whoever is selling pacu fish don't know the wildlife laws.
"They're just there," he said. "You can even buy them with the internet."
Mitchell said that, in 26 years, he has seen about 10 to 12 pacu fish in Arizona waters.
Game and Fish in Tucson stocks lakes with rainbow trout in cold-weather months and catfish and sunfish in warm-weather months, according to Hart.
He said he wants to raise awareness of the problem with non-native species and suggested people find a better option to get rid of pacu, like taking it back to the pet store.
Airola, too, is aware of the issues of dumping pacu fish into lakes and ponds. He said customers who can no longer take care of the fish may bring it back to the Ocean Floor, which gladly takes fish back on donation.