Desert Tsunami Filmed in Death Valley Oasis for Endangered Fish

An earthquake in Mexico has resulted in 4-foot waves crashing around a cave as far away as Death Valley.

The earthquake, which hit Mexico's western states of Colima and Michoacán on September 19, had a magnitude of 7.6. Over 1,000 miles away in Death Valley's Devils Hole, the effects of the earthquake's tremors could be seen via large waves in the water within the cave.

Death Valley, which holds the record for the highest temperature ever recorded on Earth, lies on the California/Nevada border, around 130 miles west of Las Vegas. According to the National Oceanic and Atmospheric Administration, Death Valley receives a mere 2.2 inches of rainfall annually on average, and can reach up to 134 F.

devils hole
Screengrab from a National Park Service video of the mini tsunami waves in Devils Hole, Death Valley. These waves were caused by an earthquake in Mexico. National Park Service

While the park itself is usually incredibly dry, Devils Hole is a geothermal cave system filled with water. This oasis is the only natural habitat for the highly endangered Devils Hole pupfish, of which there are only between 100 and 180 present in the wild, according to the National Parks Service. Devils Hole is over 430 feet deep, although pupfish only occupy the upper 80 feet.

The water in Devils Hole is usually calm, carbonate-rich and oxygen-poor, and sits at an average temperature of around 93 F. The pupfish depend on algae growing in the warm, still waters.

However, this week's earthquake was so powerful that its shockwaves resulted in 4-foot-high waves crashing across the cave system, 22 minutes after the initial quake in Mexico.

"The 7.6 magnitude event struck near the Colima-Michoacan border at 11:05 AM local time (PDT; 1:05 PM at the epicenter). NPS [National Park Service] staff were onsite conducting research and witnessed the effects firsthand. Within five minutes, the normally still water in the pool began slowly moving, and soon built to waves several feet high," the Death Valley National Park wrote in a Facebook post.

Despite the fish being endangered and used to their tranquil pool, NPS thinks that the waves may prompt spawning, resulting in more fish being born in Devils Hole.

"The highly endangered Devils Hole pupfish (Cyprinodon diabolis) has thankfully evolved with these types of periodic natural disturbances, and they were fine and swimming (happily?) afterward," Death Valley National Park said. "Keeping with previous observations, staff expect to see an increase in spawning activity over the next few days, hopefully resulting in even more recruits into the population."

A similar population boom occurred after other earthquakes resulting in similar standing waves in Devils Hole: the 2012 Guerrero–Oaxaca earthquake, the 2018 Gulf of Alaska earthquake, and the 2019 Ridgecrest earthquakes all caused waves that scour the algae from the rocks (including eggs and larva), affecting the food availability for the fish.

Death Valley has experienced some other strange water-based weather events recently, with torrential rains in the aftermath of the California heat wave at the beginning of September resulting in flash flooding and waterfalls, which were so destructive that they caused large amounts of damage to the road structure.