Whether viewing it from the ground or from the air, at first glance, much of Nevada may appear as a vast wasteland of desolate desert. This could not be further from the truth. Nevada, which lies within both the Great Basin and Mojave Desert, is one of the most diverse states in the nation in terms of biodiversity, topography, and geography.
Nevada has 314 named mountain ranges separated by valleys or basins. Often referred to as the basin and range state, this multitude of mountain ranges makes Nevada the most mountainous state in the country. Nevada’s biological diversity correlates to its geographical diversity. Due to drastic changes in elevation between these valleys and mountain ranges, Nevada is home to an impressive diversity of species, ranging from those adapted to the desert to those adapted to riparian, forest, and alpine habitats. In many cases, this unique and distinctive geography results in the separation of species, leading to new species or subspecies - 309 of which are endemic to Nevada and found no where else on earth.
Nevada is 11th among all states in total species diversity, 6th among all states in number of unique (endemic) species, including 64 recently discovered endemic species of springsnails, 8th among all states in butterfly diversity, and 9th among all states in mammal diversity. However, partially due to the high amount of endemism in the state, Nevada is 3rd among all states in having the highest number of species at risk.
The Nevada Natural Heritage Program (NNHP) is currently tracking over 600 species on either the tracking list or the watch list. Species placed on the tracking list are those species that NNHP actively maintain inventories for, including compiling and mapping data; regularly assessing conservation status; and providing information for proactive planning efforts. These species generally are ranked S1-S3, typically have federal or other state agency status, and are considered at highest risk of extirpation or extinction.
Species placed on the watch list are those species that are considered to be of long-term concern. In some cases, these species are showing a declining trend, but overall their population numbers are still robust; in other cases, the species may have recently been removed from the tracking list but are still being monitored in the event their status changes. NNHP passively collects and maintains data on these species.