Warmer ocean temperatures associated with the El Niño climate phenomenon could lead to the highly venomous yellow-bellied sea snake appearing in Southern California waters, according to scientists.
El Niño is characterized by warmer-than-average ocean surface temperatures in the central and eastern tropical Pacific. These conditions can push marine species typically found in warmer, tropical waters into areas they do not normally inhabit. "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 aquatic marine reptile known for its potent venom, which contains neurotoxins and myotoxins. Its appearance is marked by a striking two-tone body, with a dark back and bright yellow underbelly, and a flattened, paddle-shaped tail.
These snakes are usually found in warm tropical and subtropical open oceans. However, unusual ocean currents and warming events can transport them into new territories, sometimes resulting in them washing ashore. The species is among the most widespread sea snakes globally and is considered extremely venomous, though it is described as having a relatively docile nature.
Southern California is currently experiencing a significant heatwave, with coastal and metro areas seeing daytime temperatures between 95 and 102 degrees Fahrenheit. While typically found much farther south, the warming waters could potentially draw them toward the California coast.
Encounters with the yellow-bellied sea snake in Southern California are rare. A documented sighting in Newport Beach in 2018 was only the fifth in the area since 1972, according to Surfer. Notably, the 2018 sighting occurred outside of an El Niño period, unlike three earlier encounters recorded during the strong 2015-16 El Niño event.
Unusual marine life sightings have not been limited to snakes. Earlier this month, a fisherman filmed a rare hammerhead shark near Malibu Pier. Data from iNaturalist indicates that hammerhead sharks had not been reported that close to Southern California beaches since 2015.