The Michigan Department of Natural Resources announced Tuesday several reports of fishermen catching an invasive species of fish with “squarish” human-like teeth that reportedly has a false reputation for eating human testicles.
“Reeling in a pacu would be a surprise, perhaps even a shock to anyone fishing in Michigan,” the DNR said a news release. “Though it looks somewhat like a native shad, the pacu’s squarish, blunt teeth clearly set it apart. It isn’t similar to any native, toothed fish, including trout, muskellunge or northern pike.”
But the scaly critter’s penitent for human flesh is overblown, if not outright false, according to a National Geographic report based on the studies of an academic at Denmark's University of Copenhagen.
"Its teeth and powerful bite can for sure be dangerous, but to [have it bite you] is highly unlikely," fish expert Peter Rask Møller said.
Multiple news reports have surfaced warning swimmers of the pacu’s nasty reputation, but don’t seem to be attributed to any official alert from wildlife authorities.
“Pacu have a bad reputation online, where many people believe they bite human testicles, allegedly confusing them with tree nuts,” National Geographic reported in 2013. “The fears have been so widespread that some officials have even suggested men swim with their bathing suits tightly tied.”
The DNR says the fish are likely found because they were aquarium pets that owners discarded in nearby lakes, ponds or rivers.
“Invasive or not--planting fish of any kind in the waters of the state without a permit is illegal,” said Nick Popoff, manager of the DNR's Aquatic Species and Regulatory Affairs Unit. “This includes the release of aquarium fish like pacus and goldfish, as well as farm-raised fish from private ponds.”
An invasive species is defined as one that is not native and can cause harm to the environment, the economy or human health, according to the Michigan DNR. The department says pacu have been caught in lakes, ponds or creeks in at least 27 U.S. states.
The DNR said three pacu have been found recently: two from Lake St. Clair and one from the Port Huron area.
“If your pacu has outgrown its tank or begun to feed on your other fish, rather than releasing it into a pond or stream, consider donating or trading it with another hobbyist, an environmental learning center, an aquarium or a zoo,” said Paige Filice of Michigan State University. “You can also check with the pet store where you purchased the fish to see if they will take it back.”