Giant Goldfish Shows Why You Should Never Flush Fish Down the Toilet

The 2003 Pixar film Finding Nemo popularized the misconception that all drains lead to the ocean, encouraging young fans to flush their pet fish down the toilet in an ill-advised bid for freedom. As experts were quick to point out following the movie’s release, flushed fish typically die long before they reach the ocean, going into shock upon immersion in the toilet’s cold water, succumbing to the noxious chemicals found in the sewage system, or—if they make it this far—finding themselves eliminated at a water treatment plant.

But what happens to the few pet fish that survive this harrowing journey, as well as those released directly into the nation’s waterways? A photograph recently posted on Facebook by nonprofit Buffalo Niagara Waterkeeper (BNW) reveals one potential outcome: A 14-inch goldfish caught downstream of a wastewater treatment plant in the Black Rock Canal of New York’s Niagara River.

The fish in question was either flushed down the toilet or set free in the river by its owner. (Jonathan Carey of Atlas Obscura points out that the Great Lakes region’s interconnected sewer system is more than a century old and, when overburdened by heavy precipitation, often dumps excess household sewage into nearby bodies of water.) Regardless of how it arrived, the former pet thrived in its new habitat, growing to an enormous size and, to the detriment of the area’s native species, operating unchecked by predators.

“Without a natural predator, they’re winning all the competition for food and resources,” Jennifer Fee, BNW’s marketing director, tells the Huffington Post’s Jamie Feldman. “They’re winning, they’re lasting longer and they’re continuing to live and grow.”

The roughly bowling pin-sized goldfish is far from the only one of its kind: In 2013, for example, a 4.2-pound, 1.5-feet-long goldfish was found in Nevada’s Lake Tahoe basin. BNW’s Facebook post further notes that tens of millions of goldfish now live in the Great Lakes, posing what the nonprofit describes as “a constant threat to the health of native wildlife populations and their habitats,” according to Atlas Obscura.

Per The New York Times’ Steph Yin, goldfish—domesticated carp originally bred in ancient China but introduced into the United States during the mid-1800s—are an “ecological nightmare.” In addition to disturbing sediment and vegetation found at the bottom of lakes and rivers, the invasive fish release nutrients capable of triggering excess algal growth; transmit exotic diseases and parasites; feast on a diverse diet of fish eggs, small invertebrates and algae; and reproduce at higher rates than most freshwater fish. To make matters even worse, David Anderson and Shira Polan write for Business Insider, goldfish are known to migrate across multiple bodies of water. Currently, the species runs rampant in such far-flung locales as London’s Epping Forest, the Canadian province of Alberta, Nevada’s Lake Tahoe Basin and Australia’s Vasse River.

Katie Morse of local news station WKBW reports that the recently publicized image is actually several years old but was posted as a reminder to never flush or otherwise release pet fish. Instead, Josh Schwartz of Elmwood Pet Supplies tells Morse, individuals who can no longer take care of their goldfish should return it to their local pet store. The U.S. Fish and Wildlife Service outlines several additional options, including putting the fish up for adoption, donating it to a local school, or even humanely euthanizing it with a veterinarian or pet stores’ assistance.

Meilan Solly | | READ MORE

Meilan Solly is Smithsonian magazine's senior associate digital editor, history.