FLORENCE, Wis. - At first, two local anglers thought they'd landed a piranha.
Mike Lutz of Iron Mountain and Mike Faccio of Beecher, Wis. were fishing on the Menominee River last week when Lutz reeled in an interesting catch. The two men figured it deserved a closer look.
Greg Matzke, Wisconsin Department of Natural Resources fisheries biologist for Florence and Forest counties, determined the fish was a pacu, a relative of the piranha.
Mike Lutz of Iron Mountain holds up the pacu he caught in the Menominee River with his fishing partner, Mike Faccio of Beecher, Wis. The fish was 2.9 pounds and 16 inches long.
"It is still a South American fish and it is hard to distinguish between the two," he said. "The main difference is the teeth. A piranha will have sharp, spiky teeth, and a pacu will have flatter teeth. They (pacu) feed on seeds, fruits and insects and most likely smaller fish species."
Piranhas and pacu are freshwater fish native to South America.
Matzke said a pacu is not considered to be the predator that a piranha is, but pacu can grow much larger.
Matzke added the DNR believes this pacu found its way into the river through a hobbyist, who purchased it through an aquarium store but no longer wanted to keep it.
"It will be two or three inches long and people will think it will stay short," he said. "Basically it outgrew its tank and then the owner didn't want to kill (their) pet, so they dumped it, which is illegal," Matzke said.
Such practices can spread diseases or otherwise disrupt the ecosystem.
Matzke added fishing for pacu or piranha is a popular sport in South America.
"There probably won't be any more," he said. "If there are more, they will die this winter. Our water is too cold."
Matzke stressed that it is illegal to transport any fish from an aquarium into a lake or river. It is also illegal to put a native fish into other waterways.
Matzke said a Wisconsin DNR official told him that this is the third report of a pacu in Wisconsin waterways this year.
"To my knowledge, this is the only one caught in this area," said Matzke. "It is a very interesting catch."
The DNR reminds fishermen to be aware of native fish.
"If they believe it to be non-native, do not release it," he said.
Matzke also said it's important for those using area waters to pay attention to signs at boat landings. All fishermen should remove vegetation from their boats, dispose of bait properly, and not transfer weeds from lake to lake.
Lisa M. Hoffmann's e-mail address is firstname.lastname@example.org.