Something truly strange has been washing up on Oregon beaches—and researchers don’t know why.  In early May, several snake-like sea monsters known as lancetfish were discovered lying about the sand along what was estimated as a 220-mile stretch of The Beaver State coastline. Dead fish on beaches aren’t unusual, but lancetfish make their home about a mile below the surface of the Pacific Ocean and are rarely documented by people. 

According to the National Oceanic and Atmospheric Administration (NOAA), little is known about lancetfish. The species’ scientific name Alepisaurus means “scaleless lizard.” Measuring up to seven feet in length, lancetfish are found in tropical and subtropical waters but are known to migrate as far north as Alaska’s Bering Sea in search of food—which is essentially anything these ambush feeders can get into their large, fang-filled mouths. 

But the oddities don’t stop there. Living in what’s known as the mesopelagic zone, or by its nickname “The Twilight Zone,” a layer of the ocean extending from 660 to 3,330 feet in depth and home to the first instances of bioluminescence, lancetfish are both notorious cannibals and hermaphroditic, possessing both male and female sex organs. 

“No one is sure why [the lancetfish] are washing ashore,” wrote Oregon State Parks in a Facebook post. “If you see one [on the beach], take a photo and post it on social media with the tag: ‘Oregon State Parks.’” 

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Since 1982, groundfish surveys, traditionally performed using deep-sea trawling gear, conducted by NOAA biologists have surfaced two lancetfish in the Gulf of Alaska, four around the Aleutian Islands, and another 10 in the Eastern Bering Sea. Having one wash up on beaches is rare but not unheard of.

While the majority of the recently beached fish in Oregon were found dead, at least one specimen was found alive. The people that found that fish reportedly “helped it back into the ocean, where it swam off.”

 Biologists can only guess as to why these deep-sea cannibals are washing onto Oregon’s beaches. Injuries are one plausible hypothesis, while illness or recent severe off-shore storms are others.