Natural History Museum Rotterdam

One afternoon in April 2016, four friends in the Netherlands got drunk, took some ecstasy, and stared into a fish tank. They were feeling particularly inspired by an old episode of the TV show Jackass—specifically, a segment in which the stunt personality Steve-O swallows a live goldfish. So they dunked their empty glasses into the tank, scooped up a small collection of goldfish one at a time, and gulped them down. The group washed down the fish with more beer.

Once all the goldfish were polished off, according to an in-depth case report published last week by physicians at Erasmus University Medical Center in Rotterdam, a 28-year-old man volunteered to take his turn with the one remaining fish in the tank: a nearly two-and-a-half-inch-long bronze catfish that another participant had found too large to ingest. A video reportedly shows the catfish swallower attempting to gulp down the flopping animal with a swig of beer amid chants of “Grote vis! Grote vis!” (“Big fish! Big fish!”).

The man began to gag. His friends watched, horrified, as he vomited beer and jammed his fingers down his throat. He started spewing blood into a bucket, and eventually was admitted to intensive care to have the fish dislodged from his throat.

Even Steve-O might have thought twice before swallowing a live catfish. Unlike the harmless goldfish, Corydoras aeneus, also known as the “Cory” catfish, is armored with strong, overlapping scales. And it shares a famous defense mechanism with almost all of its catfish cousins: spinelike barbs embedded within each fin. When the fish is distressed, these barbs straighten and lock into place, turning the animal from a tropical pet into a sort of aquatic shuriken.

When the man arrived at the hospital, all he was able to tell doctors through the drugs and alcohol was that he was having trouble swallowing, according to Linda Benoist, the Erasmus otorhinolaryngology resident who treated him. It wasn’t until the doctors spotted a fin in his throat that he could recall more specifically what had happened.

A CT scan shows the tightly lodged fish (Linda Benoist / Erasmus University Medical Center).

This is far from the first time someone has swallowed a live fish. What’s rare is for it to turn into a medical emergency: A recent study found 75 recorded cases of live-fish aspiration over the past several centuries, only four of which were voluntary. But those reports only account for failed attempts to down live fish. The practice has been a go-to gag for American goofballs and pranksters for decades. As panty raids, planking, and eating Tide Pods have come and gone, fish swallowing has remained—usually in the form of goldfish, and sometimes minnows or other teeny-tiny species.

The father of modern goldfish swallowing, the lore goes, was—perhaps unsurprisingly—an 18-year-old college student. In 1939, Lothrop Withington Jr., a freshman at Harvard, reportedly prompted a friend to issue him the challenge alongside a $10 payout. The stunt was considered so outlandish at the time that the crowd that showed up to watch the spectacle contained multiple reporters. By all accounts, Withington chewed.

As The Harvard Crimson later recounted, Withington’s bold challenge quickly caught on. A Harvard sophomore won local notoriety—and job offers from multiple circuses—that same year after swallowing 23 goldfish in just 10 minutes. Soon students at other schools were vying to break the record, and the Intercollegiate Goldfish Gulping Association (IGGA) was established to determine and enforce competition standards. There were only two rules: first, that each fish measured three inches long, and second, that the fish be kept down for at least 12 hours after consumption. Challengers emerged from campuses far and wide, until the last title on record went to Clark University’s Joseph Deliberto, who sucked down 89.

The height of the craze (and the IGGA) lasted only for the school year, but fish swallowing has never really gone away. Pushback from animal-rescue groups led most colleges to outlaw the practice in the early 1940s, which likely helped fuel the rise of goldfish gulping as a fixture of collegiate hazing rituals. It’s now regularly listed as an offense on lawsuits and sanctions brought against fraternities and sports teams. In addition to Jackass’s rendition, the practice has popped up in at least three major films spanning four decades: A Fish Called Wanda, The Wolf of Wall Street, and, most recently, Aquaman. YouTube is full of videos of people of all ages throwing guppies down their gullets.

Even with restrictions in place, students have long played drinking games that incorporate the spirit of Withington’s original bet, chasing with beer just as their parents’ generations did. At Colby College in Maine, swallowing goldfish is a tradition during Doghead, an annual booze-soaked St. Patrick’s Day celebration with murky origins. A Petco employee in the nearby town of Augusta told me that he’s learned to spot Colby students shopping for Doghead goldfish each March and tries to avoid selling them any. (He asked to remain anonymous, since he’s not authorized to speak for Petco.) Several other pet stores in the area carry only other types of fish.

In 2014, PETA implored Colby to put an end to the Doghead tradition. The college has noted that it does not sanction or support Doghead, and that “swallowing live goldfish is unsafe and at odds with Colby’s institutional values.”

Fish swallowing hasn’t been limited to campuses. Kate Paschal, the mother of one of my colleagues, remembers swallowing a goldfish at a youth-group event in the mid-’80s. She says that the youth pastor at her evangelical church in Iowa suggested the activity and sent parent chaperones out to purchase the fish. “Only a few of us participated,” Paschal says. “But I was the one who would tend to do stuff like that … It was pretty slippery and slimy. But I was probably too full of adrenaline to think about the taste.”

A few cases of goldfish swallowing have resulted in police involvement. On January 8, 21-year-old Maxwell Taffin was arrested and charged with animal cruelty for allegedly swallowing a friend’s pet fish in a Louisiana State University dorm room. A year ago, a British man faced similar charges for a fish-swallowing video uploaded to Facebook.

The dubious legality of gorging yourself on goldfish raises an odd question: Where is the line between pet fish and food fish? Swallowing goldfish poses little health risk, and the fish are hardly rare or endangered. In other parts of the world, live seafood remains a delicacy rather than a crime. Korean sannakji is a specialty dish of live octopus served freshly dismembered (and still squirming) beneath a garnish of sesame oil and toasted sesame seeds. Odori ebi, or “dancing shrimp,” half-drowned in sake, are eaten in both Japan and Thailand. Yet many countries, including a few where these dishes have originated, have struck them from the menu over animal-cruelty concerns.

Living creatures with highly effective defense mechanisms, meanwhile, seem obviously unfit for consumption. The man who swallowed the catfish is now alive and well, though he has been careful not to share his name publicly, for fear of retaliation from animal-rights activists. The fish itself wasn’t so lucky: It died from either an onslaught of beer or simply being outside its tank for too long.

Even so, the fish has achieved eternal fame at the nearby Natural History Museum Rotterdam, where it remains a top attraction at the Dead Animal Tales exhibit, a grisly array of some of humankind’s most unfortunate encounters with the animal kingdom. The fish is mostly intact, but its tail mysteriously disappeared during the ordeal. It might have been the only part of the fish to actually make it down. The Intercollegiate Goldfish Gulping Association would be proud.

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