Death Valley National Park Records ‘Increased Numbers of One of World’s Rarest Fishes’ For First Time In Decades

by Amy Myers

Officials in Death Valley National Park happily announced that its pupfish numbers in Devils Hole are on the rise. Pupfish are notoriously rare. For decades, they have been fan-favorite residents of the deep, water-filled cavern. However, for a while, scientists worried that this species was on its way out – until now.

Recently, Death Valley scientists counted 175 pupfish in Devil’s Hole, the most that they’ve seen in the past 22 years. The U.S. Fish and Wildlife Service worked with the Nevada Department of Wildlife and National Park Service staff to manage the “critically endangered” species. Pupfish are small, silvery fish with several dark bands along their sides. They are one of the world’s rarest fish and are able to survive in the extreme temperatures of Devils Hole.

Located near Ash Meadows National Wildlife Refuge in Nye County, Nev., Devils Hole is a detached unit of Death Valley National Park. According to NPS, “Devils Hole pupfish (Cyprinodon diabolis) live in the upper 80 feet of a deep water-filled cavern and sun-lit shallow pool at the cavern’s entrance, making this the smallest range of any vertebrate species on the planet.”

In order to determine the state of the population, observers used scuba gear. In fact, this is actually the 50th anniversary of the park using the special equipment, making their latest findings even more special. Scientists dove into Devils Hole, starting at depths below 100 feet. Meanwhile, other scientists counted the rest of the pupfish population at the surface along the shallow shelf.

Among the staff at Devils Hole was Brandon Senger, Supervising Fisheries Biologist for Nevada Department of Wildlife, who observed a surprising amount of young fish below the surface. Additionally, fellow biologists noted that the pupfish were in “remarkable condition” and were also “very active.”

Rare Fish Population Bounces Back After Two Decades at Death Valley National Park

Back in the 80s, Death Valley National Park saw pupfish numbers of around 200 in the springtime. Unfortunately, the population fell to just 90 fish within the past 20 years. This year’s findings happen to be the largest found since April 2000. Over the last nine years, the population has continued to build since its all-time low count of just 35 fish.

Kevin Wilson, Aquatic Ecologist for Death Valley National Park, who manages resources in Devils Hole, stated, “such shifts highlight the importance of maintaining long-term data as we work to find out what’s changed.”

Not surprisingly, biologists are happy to see that the species seems to finally be recovering.

Michael Schwemm, Senior Fish Biologist for the US Fish and Wildlife Service, shared, “it’s exciting to see this shift, because if persistent, allows more opportunity for study and to explore new management options.”