Not Even The Tiny Devils Hole Pupfish Can Escape the Effects of An Earthquake

Among fishes, perhaps none are watched as closely as the Devils Hole Pupfish, which live on the very brink of extinction in a tiny, 10-foot by 50-foot warm spring that is part of Death Valley National Park. Via two video cameras -- one above the water's surface, the other underwater -- researchers keep tabs on the fish.

And that's how they captured the effects of a recent earthquake -- caused by the magnitude 7.2 El Mayor - Cucapah earthquake and an immediate aftershock that occurred on April 4 -- on the small pool of water.

According to USGS researchers, the 93-degree water at Devils Hole is "generally very still and although clear, quite stagnant. Thus, the movement seen in this video is thought to represent a fairly great disturbance to the shallow feeding/spawning shelf. The shelf substrate, consisting largely of sand, gravel, and cobble, was largely redistributed as a result, changing the topography fairly drastically. The entire video (not shown) shows fish returning to the shelf starting about five minutes after the water movement ceases."

According to a USGS release, "federal and state surveys done within a week after the April 4 earthquakes revealed about 118 individual fish in the pool, an increase from about 70 the year before. Also, biologists saw newly hatched larval fish and evidence that the fish were spawning.

"The violent oscillations, though, washed away algae that are essential to the food web of the critically endangered fish, though biologists hope they will grow back quickly," the release added.

Devils Hole pupfish populations numbered about 400-500 individuals until the late 1960s, when the water level in the pool dropped in response to pumping of nearby irrigation wells, according to the USGS. "Pupfish numbers declined precipitously, and though water in Devils Hole is now maintained at a minimum level, the pupfish are still greatly imperiled," the agency notes. "With intensive management efforts, pupfish numbers are increasing from a critical low of just 38 individuals in 2006 to about 118 in the 2010 spring survey after the recent temblor."

The video, taken April 4, runs just short of 4 minutes.