The Endangered Pupfish of Death Valley National Park

The Endangered Pupfish of Death Valley National Park

Native to Devil’s Hole near Death Valley National Park, the Devil’s Hole pupfish is described as the world’s rarest fish species. With a population of less than 200 in 2005, and only 115 known to remain as of 2016, this tiny, bright blue fish measuring only one inch in length, has been considered critically endangered since 1967.

The Devil’s Hole pupfish, or Cyprinodon diabolis, are located in the Amargosa Valley area of southwest Nevada, east of Death Valley. Devil’s Hole is a limestone cavern containing a geothermal aquifer-fed pool. According to studies, the species is thought to have evolved about 60,000 years ago, around the time the cavern became exposed to the surface. Due to the fragility of the surrounding ecosystem, the water has been monitored regularly by government agencies for depth and nutrient content, as well as other factors that may affect the fish’s survival. Agricultural competition for water, pumping in the surrounding area, and even earthquakes has resulted in fluctuating water levels since surveying began.

Although they have been found in deeper water, pupfish primarily feed and spawn in a shallow portion of the cavern only 6 by 13 feet in area. Their diet consists of nutrients derived from a layer of algae growing on the bottom shelf, where the shallow pool receives ample sun exposure. With water temperatures at 93 degrees and oxygen levels typically deadly to fish, the pupfish are adapted to their surroundings. However, if the fragile environment becomes too altered, they are unable to be moved to a new home because of the unique conditions in Devil’s Hole.

In April of 2016, surveillance cameras captured video of three men breaking into the fenced area surrounding Devil’s Hole. According to authorities who reviewed the video, the men had been drinking and firing a shotgun. One of the men went skinny dipping in the shallow area of the pool, disturbing the algae and leaving behind dirty boxers, beer cans, vomit, and at least one dead pupfish. Because of the lack of natural predators, pupfish tend to be docile and curious by nature, putting them at greater risk of being harmed during such an intrusion. With April and May being peak spawning season, the National Park Service also expressed concern over the possibility that pupfish eggs had been crushed during the vandal’s skinny dipping spree. The men were charged with the killing of an endangered species and destruction of habitat, as well as trespassing and destruction of property.