Scientists Target Remote Desert River for Intensive Study
There are only two rivers in the California portion of the Mojave Desert where water flows year-round. The Amargosa River is one. It is home to rare plants and animals, such as the Amargosa pupfish, that are completely dependent on this groundwater-fed river. Some organisms, like the Amargosa vole, live nowhere else on Earth.
While most of the lands surrounding the river have been protected through private and public conservation efforts, the water itself has not. If over-pumping causes regional groundwater levels to drop, the Amargosa River is in danger of drying up.
But what exactly lives there and why should we care?
Forty-five years ago, a cross-disciplinary team of scientists thoroughly catalogued plants and animals along the Amargosa. The result of that effort was the Bureau of Land Management’s decision to establish an Area of Critical Environmental Concern along the river, and 26 miles of the Amargosa were later designated a Wild and Scenic River by Congress, a special status granted to just one percent of the river miles in California.
The 2016 Desert Renewable Energy and Conservation Plan also requires that this desert river be managed for conservation. Despite these special designations, the persistent threat of groundwater depletion looms large; too much pumping, and the river could disappear.
If we are going to conserve the Amargosa, we must know what is there. To this end, we launched a new science expedition along the Amargosa this spring to see what has changed since 1972. We called it an Expert BioBlitz, and it included a multi-disciplinary science team to inventory the plants, invertebrates, fish, amphibians and reptiles, birds, and mammals along the river. Scientists from The Nature Conservancy, the federal Bureau of Land Management, the Los Angeles County Museum of Natural History, the Rancho Santa Ana Botanic Garden, and dozens of other organizations all volunteered their expertise.
This year our botany team found blue-eyed grass and California sawgrass clinging to the sides of the pale purple and honey-colored cliffs that line the river. These plants are part of the Amargosa’s spring-feed “hanging gardens,” unique patches of rare desert wetland habitat fed by groundwater from hundreds of miles away. The same freshwater springs that emerge from the cliff faces also support unique species of native aquatic snails, which our scientists are currently working to identify.
Reptile and amphibian expert participants ventured out at night to delineate the ranges of Woodhouse’s, western, and red-spotted toads, and during the day to document desert iguanas, geckos, and zebra-tailed lizards. While wind scorpions and wolf spiders were noted in the field, many of the smaller invertebrates found during our BioBlitz await identification in the lab, under microscopes, where comparisons with museum specimens can be made.
While the Amargosa River supports a unique slice of California’s biodiversity, this place is also special because its plants and animals bolster the local economy. Tourism has replaced mining as the primary industry. Birders, hikers, super-bloom enthusiasts, and other visitors venture there to enjoy nature. Local business owners have gone beyond passive coexistence with the local flora and fauna; they actively conserve and restore lands that they own to better support rare plants and wildlife and to facilitate public access. Visiting this area, it is easy to see how endangered species recovery and business development are occurring hand-in-hand. The mutually beneficial relationship between people and nature in the Amargosa region serves as a model for other parts of California.
Nearby Ash Meadows features crystal-blue pools fed by the same groundwater that feeds the Amargosa River. It was once slated for subdivision and development, a decision that could have spelled extinction for dozens of species. Instead, Ash Meadows was conserved as a national wildlife refuge after scientists revealed its importance to rare desert pupfish. The nearby town of Shoshone aspires to similar results for biodiversity, but by marrying ecotourism with conservation, also preserves a healthy local community and economy.
While the Amargosa region is not on most Californians' radar, it exemplifies the uniqueness of our state as well as the innovation that we prize. At a time when California’s future is so closely tied to natural resources, especially water, a desert river that supports wildlife and rare plants is a special place that deserves our protection. Now that we’ve returned from our BioBlitz, we will tally our findings, share our results, and see if science can again catalyze conservation action to protect the river, its groundwater sources, and its diverse life, as it did 45 years ago.
Banner: Sunset at Ash Meadows National Wildlife Refuge | Photo: USFWS
