Whale sharks and hammerheads have turned up off Southern California as an unusually strong El Niño pushes warm water north, according to a Reuters report datelined Dana Point on Oct. 17. Sightings of whale sharks off California are rare enough to stand out.
The sharks are part of a wider group of unusual visitors. Reuters also reported a first-ever sighting of a longfin bigeye, the first sea turtle nests recorded on California beaches and a venomous yellow-bellied sea snake that came ashore.
A-Z Animals, in a story republished by Yahoo News, says hammerheads and whale sharks have been seen off Southern California in recent weeks. It puts the water off Dana Point at roughly 72 degrees Fahrenheit (22 degrees Celsius) in mid-October. It says a rise of just 2 to 3 degrees is enough to draw tropical and subtropical fish north.
The same article says the sharks are following small fish, including anchovies, sardines and mahi-mahi, riding the warm current. We could not confirm that feeding explanation in the Reuters reporting, so treat it as the outlet’s account.
The sea snake story has been told more dramatically than the facts support. Local reports describe a single sick snake found at Crystal Cove State Beach on Sept. 11, according to Edhat, citing CBS Los Angeles. Experts said it appeared to be a yellow-bellied sea snake.
The Natural History Museum of Los Angeles County puts the state’s tally of verified encounters with this snake at six or seven, with the latest during the 2015–16 El Niño, according to Rolling Out.
El Niño is a natural climate pattern that recurs every few years, Reuters reported. None of the sources we reviewed ties the whale shark sightings to long-term climate change.
A-Z Animals adds that warm water can delay the upwelling of cold, nutrient-rich water that kelp, krill and baitfish rely on in fall and winter. The outlet says this can ripple up the food chain to sea lions and seabirds. That is the outlet’s own assessment, not a finding from a study.
For now, the unusual visitors are expected to be temporary. Reuters reported that conditions should largely return to normal once El Niño ends, which 1News reported as 2027.
Source: Reuters (via U.S. News & World Report), A-Z Animals (via Yahoo News), Edhat
