Ground-water is the Ultimate Source of the Salt Creek Pupfish Habitat, Death Valley, U.S.A.

We report δ18O and δD stable isotope compositions of water collected at several sites in northern Death Valley, including the Salt Creek pupfish (Cyprinodon salinus M.) habitat in Mesquite Flat basin. Various theories exist concerning the source of water for Salt Creek, including snowmelt and precipitation, as well as contribution from ground-water. A comparison of Death Valley waters to the Global Meteoric Water Line indicated that none of the rain or snow samples are reasonable candidates for habitat source water; however, all of the ground-water sampled could serve as the source water for the progressively evaporating pupfish habitat sites.