The number of wild horses able to survive and thrive in the Virginia Range without destroying the rangeland is currently set at 552, but even that figure is subject to debate because the 85,000-acre study area is just a fraction of the range's total, 360 square miles.
Conducted in the fall and winter of 1999 by Range Management Specialist Gary Brackley, of the United States Department of Agriculture Natural Resources Conservation Service, the study focused on the amount of available forage. A number of factors, including accessibility were considered.
For example, forage on a steep hill can be almost impossible for the horses to access and cheat grass is desirable forage, but very dependent on the amount of rainfall in any given year, according to Brackley.
Storey County depends on the wild horses to keep the fire hazard down by eating cheat grass. The study's final figure, 552 horses, is based on the horses eating 20 percent of the total annual cheat grass available.
Horses in the Virginia Range will consume 800 pounds of dry forage per month and the study concluded that 280 horses could be supported in the study area if no cheat grass is consumed. This second figure is Brackley's recommendation.
These figures could fluctuate over time relative to range conditions, but overall the news concerning range quality is not good.
With few exceptions, forage use was categorized as heavy on the range to severe in riparian areas, resulting in a rangeland that cannot continue to sustain forage growth over the long term.
This loss of plants increases the potential for soil erosion and sediment production that adversely impacts water quality. Streams drain into the Truckee River, potentially endangering two threatened species, the Cui-Ui and Lahontan cutthroat trout, said the study.
Brackley said extrapolating these figures to include the whole, 360-square-mile Virginia Range could be dangerously inaccurate, and also recommends a study be done every year.
The study cost $10,000 and was funded by the state department of agriculture and the Virginia Range Wildlife Protection Agency.