Only a few hundred Devils Hole pupfish live in an isolated pool in the desert, where occasional floodwaters roil their habitat.

Devils Hole pupfish, living within a single pool in Death Valley National Park, have clung to their existence under the watchful eyes of ecologists and public agencies. Numbers of the uniquely isolated and critically endangered species have ebbed and flowed with shifting conditions and nearby development. Now, researchers have identified a new factor that could cause fluctuations in the famously fragile population: flash floods.

Sudden pulses of rainfall, projected to grow more intense with climate change, stir the species’ cavernous habitat, researchers reported at AGU’s Annual Meeting 2023 in San Francisco. The fish have a tangled relationship with the sediment that floods add to their natural fishbowl. The finding offers state and federal agencies deeper insight into how the fish adapts to its harsh environment.

“Devils Hole is a really small ecosystem that responds very quickly to climate stresses,” said the study’s lead author, hydrologist Mark Hausner of the Desert Research Institute in Nevada. Floods disturb the ecosystem in the short term, he said, but could generate a greater food source for the pupfish in the long run.

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