Since Death Valley is one of the hottest and driest places on earth, bighorn sheep need the water that springs and other wetlands provide in order to survive. Burros also will use these same water sources, and will typically consume water at the rate of five gallons per day. Bighorn sheep are normally very timid and are easily outcompeted for available water sources by the more aggressive feral burros. Burros in Death Valley also are known to foul spring sources or consume the vegetation around the rare wetland habitats in the park. This in turn makes these unique areas less appealing to other forms of wildlife such as songbirds and amphibians.
Burros also eat much of the forage that bighorn sheep depend upon.
If you have ever been to this sparsely vegetated environment, you can understand that is a significant amount of forage that could be consumed by the native wildlife species. Since burros do create a significant environmental impact, the National Park Service proposed a burro removal and control program in the early 1980's in what was then Death Valley National Monument. Several alternative proposals were presented, promoted by various groups, and evaluated through a public review process. All proposals went through multiple public hearings and the courts have reviewed many. After years of effort, a burro management program was developed for Death Valley in 1982.