Reputed Testicle-Eating Fish with Human-Like Teeth Caught in Michigan

Gentlemen, cross your legs before you read this one: A South American fish with a nasty reputation for feasting on human testicles is showing up in Michigan waters.

Two of the piranha-like fish with human-looking teeth and powerful jaws for ripping open nuts — the kind that fall from trees — and grinding down seeds were reeled in by Lake St. Clair anglers last month, the Michigan Department of Natural Resources said in a statement. Another was caught in the Port Huron area.

The Michigan DNR isn’t as worried about men’s testicles — more about that in a bit — as it is about how the toothy red-bellied pacum ended up in the state’s prized lakes in the first place.

The United States leads the world in importing ornamental fish, supporting a worldwide aquarium industry that tops $1 billion annually, the DNR said. Most likely, the fish outgrew their aquariums — they can reach up to 55 pounds — and were released by people who didn’t know what else to do.

“Pet release is almost never humane. Pets released from confined, artificial environments are poorly equipped to fend off predators and may be unable to successfully forage for food or find shelter,” Nick Popoff, manager of the DNR's Aquatic Species and Regulatory Affairs Unit, said in a statement.

“Those that do succeed in the wild can spread exotic diseases to native animals,” he said. “In the worst-case scenario, released animals can thrive and reproduce, upsetting natural ecosystems to the degree that these former pets become invasive species.”

Common Dilemma

So, what should you do? It's a common dilemma, according to the DNR.

“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 Michigan State University’s Paige Filice, who works with a new statewide campaign, Reduce Invasive Pet and Plant Escapes, or RIPPLE.

Also, Filice said, the pet store may be willing to take it back. Another option is to talk with a veterinarian or pet retailer about humane methods to dispose of the pet.

The good news is that pacus are not considered invasive species in Michigan. They flourish in tropical climates, but aren’t likely to survive the harsh winters in the Great Lakes area, but DNR officials say that warming waters due to climate change could increase the possibility that pacus could become invasive.

“Invasive or not, planting fish of any kind in the waters of the state without a permit is illegal,” Popoff added. “This includes the release of aquarium fish like pacus and goldfish, as well as farm-raised fish from private ponds.”

Pacus have been caught in lakes, ponds or creeks in at least 27 U.S. states. However, there is no evidence that breeding populations have been established in any of these locations.

How Pacus Got Their Nasty Reputation

Pacus earned their nasty reputation for feasting on male genitalia after Animal Planet host Jeremy Wade featured them on “River Monsters” in 2011. The story of two Amazonian fishermen who died after their testicles were bitten off by pacus went wild on the internet.

The legend grew when the pacu reportedly showed up in Denmark three years ago, leading a fish expert at Denmark’s University of Copenhagen to warn male swimmers against skinny dipping in the Baltic waters. And in Papua New Guinea in the southwestern Pacific, the invasive species is blamed for castrating a couple of local fishermen.

The recent pacu catches weren’t the first from Lake St. Clair. Two years ago, another angler pulled a pacu from the lake.

Image credit: Michigan Department of Natural Resources