As ocean temperatures climb, scientists say Southern California could see an unexpected—and highly unwelcome—visitor: a venomous sea snake powerful enough to pose a deadly threat to humans.
Researchers warn that warmer waters linked to El Niño, the naturally occurring climate pattern that raises sea-surface temperatures across the central and eastern tropical Pacific, may create conditions that draw the yellow-bellied sea snake closer to Southern California’s coastline.
“Some of these kinds of interesting oddities that are never a part of California will become part of this temporarily tropical El Niño-heated California,” Douglas McCauley, director of the Benioff Ocean Initiative at UC Santa Barbara, told USA Today.
The yellow-bellied sea snake is a fully marine reptile known for both its striking appearance and potent venom. It is easily recognized by its dark brown or black upper body, vivid yellow underside and flattened, paddle-like tail, which allows it to move efficiently through the ocean.
Normally, the species lives in warm tropical and subtropical waters far from California. But scientists say shifting ocean currents, marine heat waves and El Niño-driven warming can sometimes carry the snakes into unfamiliar regions, occasionally leaving them stranded on beaches.
Considered one of the most widely distributed sea snakes on the planet, the yellow-bellied sea snake is also regarded as one of the more dangerous because of its highly toxic venom.
Although the snake is not typically aggressive, its bite can be severe. According to the Australian Museum, its venom contains strong neurotoxins and myotoxins, compounds capable of attacking the nervous system and damaging muscle tissue.
The species is most commonly found much farther south across the Pacific and Indian oceans, but increasingly warm ocean conditions could make rare sightings in Southern California waters more likely.
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Southern California is also experiencing a major heat wave this week, with daytime temperatures reaching between 95 and 102 degrees Fahrenheit in coastal and metro areas.
A yellow-bellied sea snake discovered in Newport Beach in 2018 was only the fifth documented sighting in the area since 1972, according to Surfer.
Unlike three earlier sightings, which occurred during the strong 2015-16 El Niño, the 2018 encounter happened outside an El Niño period.
And sea snakes aren’t the only unusual animals turning up near Southern California’s coast.
Earlier this month, a Los Angeles County fisherman filmed a rare hammerhead shark near Malibu Pier.
According to iNaturalist, the species had not been reported that close to Southern California beaches since 2015.