COPYRIGHT T. M. BAUGH, USED BY PERMISSION

Figure 1. The tiny Devils Hole pupfish is less than an inch (2.5 cm) long but has played a big role in native species conservation.

The diminutive Devils Hole pupfish (Cyprinodon diabolis, fig. 1) in Death Valley National Park (California and Nevada) has played an outsized role in the history of native species conservation, including helping to motivate one of the earliest uses of federal reserved water rights to protect habitat of a species of no recreational or commercial value. However, water levels in Devils Hole are dropping and species numbers are declining (fig. 2). After more than three decades of research and monitoring, managers and researchers still do not have a complete understanding of the ecosystem of Devils Hole.