Hidden within the Meadows: Devil’s Hole Pupfish

Miracle in the Mojave // Lurking unsuspectedly in the middle of the desert lies the Devil’s Hole Pupfish. These fish are one of science’s biggest mysteries, with questions about  their ability to potentially make ethanol as well as their endurance to survive for potentially thousands of years. (Photo courtesy of Creative Commons). 

Hidden within the Ash Meadows National Wildlife Refuge in Nye County, Nevada lies some of the rarest vertebrate species on the planet. The Devil’s Hole Pupfish, scientifically known as Cyprinodon diabolis, is a fish that is exclusively found in Devil’s Hole, Nevada. A miracle in the desert where the entire population breeds and feeds on a singular side of the limestone cave of Devil’s Hole that’s less than 20 square meters wide which is no larger than a rectangular office desk. 

Ditch of the Desert // Swimming within Devil's Hole, the Devil's Hole Pupfish live within a small subsection of the underwater cave. These fish may be small in size and population, but are one of science's greatest Nevadan mysteries.

These fish are only approximately 0.9 inches long. Males are known for their shiny blue scales, while females typically are a brownish-yellow. The survival rate for viable eggs after reproduction is incredibly low. A pupfish that survives to adulthood is even lower. Despite the difficulties these fish face to even live, they choose to do so anyway. Every fall and spring, the pupfish population is counted by scientists: the most recent finding in spring of 2025 found only 38 pupfish. 

The actual environment of Devil’s Hole is incredibly unique. The hole is at least 450 feet deep, though pupfish have only been found at a lowest point of 80 feet. The hole is located in the middle of the Mojave Desert, which is home to some of the hottest temperatures ever recorded on Earth. Surprisingly, Devil’s Hole, in the small subsection where pupfish reside, has an average temperature of 91 degrees Fahrenheit even in the summer, where temperatures in the Mojave can peak up to 121 degrees.

Within the hole, pupfish have been discovered to feast on the other organisms that also reside in the dwelling. These other sentients include snails, algae and other crustaceans. However, these fish are preyed on by the species Neoclypeodytes cinctellus, which is a species of water beetle.

The Devil’s Hole Pupfish is considered to be a critically endangered species. Because they’re only found in Devil’s Hole, which is considered to be an unreliable environment (granted that it is a water cave found in the midst of a desert), the pupfish are dependent on the hole for survival. In the state of Nevada, they are a protected species and legally recognized as being endangered. The state has spent at least $2.5 million on the conservation of the pupfish. 

Altogether, one of the most fascinating fish to ever exist is in one of the most unsuspected places ever. In the middle of the Mojave Desert, within a small limestone water cave, swins the Devil’s Hole pupfish, who work diligently just for survival. Perhaps humanity should take note.