Tokyo Olympic officials are closely monitoring the waterway where canoeing and rowing events are to take place for an unusual threat: Rogue oysters.
The Olympics, which were already postponed last year due to the coronavirus pandemic and in the midst of a fresh outbreak, are bracing for the possibility of an influx of shellfish at the Sea Forest Waterway after organizers spent an estimated 140 million yen (around $1.3 million) in repairs, according to the BBC.
An infestation first came to light during a trial event in 2019, shortly after the venue was created. Equipment floating in the water suddenly began to sink, prompting crews to investigate what was weighing them down.
To their surprise they found an army of oysters - fourteen metric tons, or about 31,000 pounds, to be precise.
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Organizers hired divers to enter the water to deep clean the shellfish-laden equipment, which had been erected to prevent waves from hitting athletes during the games or from disrupting the route.
"The running of the race must not be influenced by natural or artificial waves," stipulates the World Rowing Rule Book. The equipment in Tokyo is reportedly able to reduce the height of waves by about 70%.
Other floats at the venue had to be dragged to the shore and replaced. Olympic officials could not immediately be reached for comment.
It's been a worry this summer in the lead-up to the boat races. "I hope none of them are attached to the devices," a staffer at a May boat-racing competition to select athletes for the Games at the same location told Asahi Shimbun. The Japanese paper described the staffer as "worriedly gazing into the water as if a monster was lurking below the surface."
Magaki oysters, also known as Pacific oysters, are native to Japan and widely upheld as a delicacy. Many chefs consider them to be among the best oysters in the world and they often sell at high value.
However, as one Tokyo government official told the outlet, "we did not consider consuming them. That would entail safety checks."
"We do not want to grow oysters but work to contain them," the official said.
International oyster expert Julie Qiu, who runs an oyster appreciation website, noted the delicacy could, in theory, be "enjoyed in various ways," from grilled, to steamed to barbecued. "Americans will know this oyster by more familiar brand names like Fanny Bay, Hog Island Sweetwater, Kusshi, or Hama Hama," she told The Washington Post in an email.
However, Qiu also stressed the dangers that come with preparing and eating Magaki oysters - which can be potentially risky to consume if they do not undergo a rigorous purification process to minimize food-borne illnesses before they are sold to customers.
What's more, "oysters that grow as hitchhikers" - such as the ones attaching to Olympic equipment - "aren't necessarily easy to open," she added. "They are probably grown in clusters and in odd shapes. I imagine that it would be a serious challenge to reclaim these oysters for public consumption."