Fish

The Amazing Pupfishes of Death Valley National Park

Home to some of the most unique and fascinating fishes in the world – the pupfish! These small but mighty fish have incredible stories, habitats, and behaviors that make them special. Let’s dive into the lives of five amazing types of pupfishes: the Saratoga Springs Pupfish (Cyprinodon nevadensis nevadensis), the Salt Creek Pupfish (Cyprinodon salinus salinus), the Cottonball Marsh Pupfish (Cyprinodon salinus milleri), the Amargosa River Pupfish (Cyprinodon nevadensis amargosae), and the Devils Hole Pupfish (Cyprinodon diabolis)!

While the pupfishes of Death Valley National Park showcase remarkable resilience, they face significant challenges today. Understanding the lives and environments of these tiny fishes can help us contribute to their preservation.

 

Fun Fact!

Did you know that pupfishes are known for their ability to adapt to extreme environments? They can thrive in some of the saltiest and warmest waters – conditions that would be tough for most other fishes to survive!

 

A scene showcasing a blue fish swimming in the foreground against a backdrop of other blue fish and rocky terrain.

Devil's Hole Pupfish (Cyprinodon diabolis)

Now, let’s explore the exceptionally rare Devil's Hole Pupfish! The Devil's Hole Pupfish (Cyprinodon diabolis) is one of the most endangered fish species in the world and is endemic to a single geographic location: Devils Hole, a deep water-filled cavern in the Amargosa Desert. This unique habitat is part of Death Valley National Park (40-acres) and adjacent to the Ash Meadows National Wildlife Refuge.

The Devil's Hole offers a stable, year-round environment with a consistent water temperature of 93°F, but it is also highly sensitive to changes in water levels. The pupfish are small, usually around 2 inches long, and come in various colors, males are a darker blue and females are moreolive green, with males displaying vibrant blue hues when spawning. Peak spawning occurs in spring and then again in early autumn..

Due to its extremely limited habitat, the Devil's Hole Pupfish is critically endangered, with current populations below historical levels.. Conservation efforts are crucial to maintaining this unique species, as they are vulnerable to changes in water availability, habitat degradation, and the impacts of climate change.

 

Male (yellow with blue fins) and female (brown with darker patches).

Salt Creek Pupfish (Cyprinodon salinus salinus)

The Salt Creek Pupfish has a rich history, having evolved from a population that originally thrived in the ancient Lake Manly over 30,000 years ago. When the lake receded, the Salt Creek Pupfish found themselves in a unique saline environment that set them apart.

Living in the winding Salt Creek, these pupfish enjoy a natural habitat that remains mostly untouched by human activity. With water salinity that can sometimes exceed that of seawater, they’ve adapted to thrive in extreme conditions! Salt Creek Pupfish are slender and usually less than 3 inches long, displaying stunning blue hues in males and beautiful silvery brown in females.

These fish can live for about one to two years, with peaks in population seen in spring and early summer. Male pupfish are known for their spirited courtship displays, defending their territories to attract females. It’s a vibrant and lively sight if you spot them during breeding season!

 

Still waters at Salt Creek.

 

Female (top) and male (bottom) Amargosa River pupfish.

Amargosa River Pupfish (Cyprinodon nevadensis amargosae)

Now, let’s shine a light on the Amargosa River Pupfish! This species (Cyprinodon nevadensis amargosae) is another remarkable resident of the Death Valley region. Like its cousins, it has adapted to survive in challenging conditions but remains distinct due to its unique characteristics and habitat.

The Amargosa River pupfish Predominantly inhabits the warm, shallow waters of the Amargosa River system. This river that orignates on the Pahute Mesa near Beatty, NV, provides a vital ecosystem for the pupfish. Their range is primarily limited to this specific waterway, making them particularly vulnerable to habitat changes.

Amargosa River Pupfish are small, usually measuring around 1 to 2 inches long, with males exhibiting a striking mix of blue and green during mating displays. Their ability to thrive in fluctuating saline levels and warm temperatures showcases their resilience. Sadly, they face threats from habitat loss, pollution, and competition with non-native species.

 

A school of small, translucent fish swims just above a sandy bottom in shallow water.

Cottonball Marsh Pupfish (Cyprinodon salinus milleri)

Exploring the Cottonball Marsh Pupfish reveals one of the most specialized pupfish in the world! Thousands of years ago, these fish made their way from the ocean up the Colorado River and into Lake Manly. The Cottonball Marsh, Salt Creek and Saratoga Spring Pupfish are from an ancient lineage that entered Lake Manly. When Lake Manly receded during warmer periods this ancient lineage became isolated in the aquatic habitats we see them today. This isolation led to different adaptations (evolution) in these extreme environments. Over time, they’ve adapted to the high salinity and extreme temperatures of this remote habitat.

Cottonball Marsh is a stunning area filled with small springs and pools. Despite its remoteness, this environment is still home to these fascinating fish. Cottonball Marsh Pupfish are relatively small, typically around 1 inch long, with striking deep blue colors in males and silvery brown in females. Interestingly, they can reproduce all year round, like many other pupfishes, however, there are certain times of year that reproduction is higher.

Visitors to Cottonball Marsh are often treated to the sight of large schools of these fish swimming together. It’s a remarkable experience to see life thriving in such extreme conditions!

 

Female Saratoga Springs pupfish.

Saratoga Springs Pupfish (Cyprinodon nevadensis nevadensis)

The Saratoga Springs Pupfish is a true survivor! This little fish descends from ancestors that journeyed all the way from the Colorado River and Lake Manly like other pupfishes. They called Saratoga Springs home after traveling through the Amargosa River. Imagine this: in 1889, scientists first described them during an expedition! It took some time for their unique status to be recognized, but today, they are celebrated as one of the oldest fish species in Death Valley.

These pupfish thrive in a special marsh filled with a mix of freshwater and some salty water. They enjoy warm temperatures, typically between 77°F and 82°F. Males stand out with their vibrant blue color, while females sport a more muted olive-brown. They average around 1.5 inches but can grow up to 2.75 inches long. If you’re visiting the springs, keep your eyes peeled for them swimming around – they’re most active in the mornings and evenings!