Watch never-captured footage of a seismic wave rocking the whole pool at Nevada's famed Devils Hole
?| March 27, 2012
U.S. National Park Service biologist Jeffrey Goldstein measures the water level in Devils Hole. Seismic waves from an earthquake 2,000 miles distant caused a tsunami to roll through the underground pool at Devils Hole in Nevada. Violent oscillations decimated the small breeding area of the endangered species of pupfish that live nowhere else on earth but in these hot waters.
Image: Peter Byrne
On March 20 a National Park Service biologist named Jeffrey Goldstein and I descended a rocky incline into the mouth of Devils Hole, a collapsed cave in the Nevada desert 40 miles south of the visitor?s center in Death Valley. Thirty feet down, an arm of water extends out from a deep pool to cover a rock shelf the size of a Ping-Pong table with up to two and a half feet of hot water. This shallow recess is home to 100 much-studied adult Devils Hole pupfish, or Cyprinodon diabolis. Living nowhere else on the planet, the pupfish receive protection from human harm by force of federal law and padlocked gates.
Shortly after 11 A.M., Goldstein was imparting the 10,000-year history of Devils Hole and its piscine denizens to me when the water level began rising and sinking by quarter-inches, then inches, then feet. As we scrambled up the rocky incline, the pool was sucked out of the hole almost entirely with a giant gurgle. It rushed back in, dislodging a metal walkway over the shelf and climbing up the sides of the hole toward us. After a few more gargles and belches, the pool waters returned to a normal level. The rock shelf had been swept clean of vegetation and pupfish eggs.
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Video: Seismic waves from an earthquake 2,000 miles distant caused a tsunami to roll through the underground pool at Devils Hole in Nevada. Violent oscillations decimated the small breeding area of the endangered species of pupfish that live nowhere else on earth but in these hot waters.
We later learned that the underground tsunami had resulted from seismic waves emanating from a 7.4-magnitude earthquake, 12 miles deep, near the Mexican state of Oaxaca, 2,000 miles distant. According to Kevin Wilson, the National Park Service's aquatic ecologist at Devils Hole, the tidal effects of earthquakes have been directly observed on only three occasions since a 1976 Supreme Court ruling preserved the Devils Hole pupfish by restricting agricultural pumping of the Amargosa Valley aquifer. "More people have walked on the moon than have witnessed the effects of an earthquake at Devils Hole," Wilson says.
[In April 2010, U.S. Geological Survey researcher Ambre Chaudoin captured a Devils Hole tsunami with cameras tightly focused on the bottom of the pool. This was the first video of such an event: Video Shows Baja Earthquake Created a Devilish "Mini-Tsunami" for Endangered Devils Hole Pupfish]
Goldstein and I captured the rare event with pocket-size video cameras, so you can share in our adventure. Even without the excitement of an underground tsunami as a backdrop, the history of Devils Hole and its pupfish residents is worth a revisit.
Isolated in the pool by retreating ice 10,000 years ago, the Devils Hole pupfish have long feasted on algae, small invertebrates and, occasionally, baby pupfish. The fish breed and lay their eggs in the shallow, 92 degree Fahrenheit water that submerges the rock shelf. The deep pool has been explored by human divers to a depth of 435 feet. The inch-long fish are known to dive down 24 meters, but they prefer to hang out on the shelf because it is covered with edible vegetation and receives occasional sunlight. Cables snake along the stone walls just above and connect to the instruments that monitor temperature and other environmental indicators. Divers count the fish twice a year. The population has ranged from 500 in the 1980s to a near catastrophic low of 38 in 2006 to 119 adults, at last count.
And what about the aftermath of our earthmoving adventure?
The walkways and instruments were repaired within hours. This type of periodic disturbance, Wilson says, is not a disaster for the fish; it resets the ecology of the pool, improving it over the long haul. Immediately after their food and eggs were swept away by the tides, the fish responded with a frenzy of mating. Environmental disaster, it seems, acted as an aphrodisiac
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