Fish with “human-like teeth” have been found in lakes in Michigan this summer, according to reports.
The Michigan Department of Natural Resources said these fish are called red-bellied pacu, which are native to South American waters and are a relative of the better-known piranha.
“The red-bellied pacu, Piaractus brachypomus, is a popular aquarium fish imported from South America,” the agency says, according to Fox59. “The U.S. leads the world in importing ornamental fish, supporting a worldwide aquarium industry that tops $1 billion annually.”
The fish have “human-like teeth” to crush seeds and nuts, the Michigan Department of Natural Resources said.
In July, two pacu fish have been removed from Lake St. Clair. Another was removed from the Port Huron area.
“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,” said Nick Popoff of the Department of Natural Resources.
The fish can be destructive to the natural environment. The fish that survive in the wild can spread “exotic diseases” to native animals in the area, Popoff said.
But, “in the worst-case scenario, released animals can thrive and reproduce, upsetting natural ecosystems to the degree that these former pets become invasive species,” he said.
The pacu have developed an odd reputation as a “testicle-eating” fish after a professor at the Copenhagen Museum of Natural History told men bathing in the area to stay alert for pacu that could mistake the reproductive organs for their favored tree nuts. The resulting reports on the fish attacking male genitals led to the professor clarifying that it was actually a joke and was’t meant to be taken seriously.
“They’re fruit eaters. Those big crushing teeth they have is for crushing seeds,” William Fink, a piranha researcher at the University of Michigan, told CNN.