The desert pupfish (Cyprinodon macularius) can survive in desert springs heated to 113 degrees. It also tolerates water twice as salty as the ocean. As hardy as it is, the pupfish must struggle to stay alive against the impacts of livestock grazing, water diversions, and exotic plants and fish. Once found thriving in seeps, springs, and marshes of the lower Colorado River, the desert pupfish now is only found in a few isolated Mojave springs in and around Death Valley and Salt Creek and San Felipe Creek in the Sonoran desert which flow to the Salton Sea.