Pupfishes of Death Valley: Hurricane Hilary impacts to Salt Creek & Devils Hole

Authors: Jeffrey Goldstein, Ambre Chaudoin, Kevin Wilson, John Wullschleger, Olin Feuerbacher, Jennifer Gumm, Danny Villanueva, Mike Bower, Michael Schwemm, Brandon Senger, Bryce Donaghue

Year: 2023

Abstract

Death Valley National Park manages conservation efforts for five species and subspecies of pupfishes (four in California and one in Nevada). On August 20th, 2023, Hurricane Hilary drenched Park Headquarters at Furnace Creek, California, with 2.2 inches (5.6 cm) of rain within 24 hours, compared to the usual annual average of 1.94 inches (4.9 cm). The National Weather Service radar indicated some parts of the park may have received around 5 inches (12.7 cm) of rain that day. As a result, the Park experienced significant flooding that destroyed roads and caused complete closure to the public for nearly two months. Flash floods drastically altered Salt Creek and habitat for its pupfish, Cyprinodon salinus salinus, and increased flows in the Amargosa River created a temporary lake within the basin of the prehistoric Lake Manly. Evidence from aerial imagery showed a possible reconnection of Salt Creek and Cottonball Marsh, hypothetically allowing brief geographic overlap of the typically isolated Cottonball Marsh pupfish, Cyprinodon s. milleri, and C. s. salinus. Saratoga Springs and the Amargosa River pupfish, Cyprinodon nevadensis nevadensis and C. n. amargosae, respectively, have not been assessed for flood impacts. Devils Hole, Nevada, received 3.66 inches (9.30 cm) over two days (August 20th–21st). Overland flow at Devils Hole did not reach flash flood levels, and the primary impact was a layer of fine sediments deposited over the shallow shelf. NPS staff and agency cooperators continue to monitor the endangered Devils Hole pupfish, Cyprinodon diabolis, which has experienced an overall increase in population size over the past several years.