The resilient, mysterious lives of pupfish
The resilient, mysterious lives of pupfish
Devils Hole is home to one of Earth's rarest species. Its population is on the rise.
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Each year, biologists and researchers gather to count a creature whose small stature can disguise its significance. As rare biodiverse aquatic desert species go, the Devils Hole pupfish is among the rarest. The enigmatic fish shines with an iridescent blue in photographs, contrasting itself against its cavernous habitat, despite being only about an inch long (a rule of thumb is a Devils Hole pupfish is about the length of a thumb).
Part of the count takes place underwater. Divers wear scuba gear and follow discrete routes through the fish’s cavernous habitat. This pupfish species, Cyprinodon diabolis, occupies the upper 80 feet of hot water in a cavern known as Devils Hole, considered the smallest known habitat of any vertebrate species on the planet. Another part of the count typically takes place above water, where a separate team of biologists record how many pupfish are gathered closer to the surface, as the Las Vegas Review-Journal’s Alan Halaly explains in this informative article about the Devils Hole pupfish count.
Devils Hole is a unit of Death Valley National Park, and the pupfish is managed by the park service, Nevada Department of Wildlife and the U.S. Fish and Wildlife Service.
Last week, the National Park Service announced increasing population numbers for the spring pupfish count. In total, the biologists recorded 191 Devils Hole pupfish, the highest number observed in more than two decades. Biologists struck a hopeful note:
“It was really encouraging to see such a large number of young fish during these spring dives,” Brandon Senger, a Nevada Department of Wildlife biologists, said in a statement. “Conditions within Devils Hole looked healthy, so we have hopes of high recruitment over the coming months that will lead to a large population in the fall."
It’s positive news for a sensitive species that has faced many threats.
The story of the pupfish is one of resilience in a limited and challenging habitat that is deeply connected to the regional geology. Eating algae and small invertebrates, the Devils Hole pupfish lives a rare, extraordinary and mysterious life. For fish, habitat is everything. And the pupfish has evolved to its narrow confines over centuries, isolated from the rest of the area about 10,000 to 20,000 years ago as the climate began to dry.
The cavern that became its home is more than 500 feet deep (according to the park service, the bottom floor has never been mapped). And it is tied to an aquifer system where groundwater discharges into springs and seeps across the area, which includes the Ash Meadows National Wildlife Refuge, a biodiversity hot spot. It is a place where groundwater connects to the surface, habitat for sensitive, small and endemic wildlife.
That the fish is protected at all is a testament to biologists, activists and politicians who have made its protection a priority. In 1952, President Harry Truman made Devils Hole a unit of Death Valley National Park by proclamation. Fifteen years later it was among the first fish listed as an endangered species. But the pupfish faced threats as water levels declined due to groundwater pumping from a 12,000-acre ranch nearby.
The National Park Service sought to halt groundwater pumping in a landmark water case, Cappaert v. United States (1976), that was decided by the U.S. Supreme Court. In a unanimous decision, the court ruled that the 1952 proclamation making Devils Hole a national monument, the president reserved enough water to ensure the survival of the pupfish, and groundwater pumping could be limited insofar that it conflicted with the habitat. With water restrictions in place, a recovery plan and eventually the purchase of land to prevent development, rare fish species in the area were on a better footing.
Researchers recorded about 200-250 pupfish at Devils Hole, when in the 1990s, the fish population began a steady decline to only 35 in 2013, the park service said. The most recent count is promising in part because it is the highest count since 1999.
The story of the rare species is not only one of resilience but one of connection — a reminder of the invisible relationships tied by geology. The water on the surface at Devils Hole is connected to groundwater, and there remain threats to the ecosystem, including a proposal to drill wells for a mining project near Ash Meadows’ borders.
But the interconnectedness of the area runs even deeper. Devils Hole is tied to global movements. Its the site of what are known as seismic seiches, waves of water sloshing back and forth that can be triggered by faraway earthquakes thousands of miles away.
The seiches are mesmerizing to watch, especially knowing that they are somehow tied to earthquakes as distant as Alaska, Mexico and Japan. It leaves me asking many more questions about this place and its geology. It makes me want to call up and interview a geologist. But I’ll leave this post here for now. Sometimes the mystery is the beauty.
In other news:
The Colorado River Indian Tribes, the Department of Interior and Arizona signed a historic agreement giving the tribe “the ability to lease, exchange or store a portion of its Colorado River water entitlement,” InsideClimateNews’ Noel Lyn Smith reports.
In the upper Colorado River Basin, six tribes entered into an agreement to formally participate in an interstate board that was previously limited to states and the federal government during its 76-year history, writes the Colorado Sun’s Shannon Mullane.
Demolition is starting on the largest Klamath River dam as attention is shifting to recovering salmon populations devastated by impoundments along the river, the Arizona Republic’s Debra Utacia Krol reports, following up on a series from last year.
The Sacramento Bee’s Ari Plachta looks at an effort to restore a floodplain at the confluence of the Sacramento and Feather rivers — with funding from a tech giant.
Lake Oroville, California’s second-largest reservoir, is full. (San Francisco Chronicle)
Environmental groups are asking a Utah judge to allow a case to move forward with major implications for the future of the Great Salt Lake, according to Fox 13’s Ben Winslow. The case centers on the public trust doctrine, a common law principle that sovereign governments have a responsibility to protect and manage natural resources for the public and future generations. Three dozen law professors filed an amicus brief in the case, urging the court not to grant the motions to dismiss (link here).