Genetically distinct from all other wild sheep on the continent, Sierra bighorn form an irreplaceable part of the landscape in which they make their homes. Beyond the ecological consequences of extinction, the loss of the Sierra Nevada bighorn sheep would have repercussions across centuries of natural and human history, leaving this great mountain range impoverished forever.
There is a lack of historical information needed to pinpoint the exact chain of events that led this species to the brink of extinction, but the earliest information on disease problems dates back to the 1870s after the introduction of extensive domestic sheep grazing throughout the Sierra Nevada. Healthy domestic sheep are well-documented to carry microbial species that cause fatal pneumonia in bighorn sheep. The initial population decline and loss of populations was likely driven by such disease episodes, continuing well into the 20th century. Unregulated hunting, especially market hunting near mining towns may have also played a role. More recently, an episode of particularly high mountain lion predation appears to have played a role. Restoration efforts during 1979-88 were successful in re-establishing populations in three areas, but governmental regulatory constraints ultimately hindered continuing recovery of these sheep relative to management of predation and threats from domestic sheep grazing very close to Sierra bighorn. It was deficiencies in governmental regulatory mechanisms that led to the seeking of federal endangered status in 1999.
Endangered species status drew attention to the plight of Sierra bighorn and garnered support for recovery efforts, which were now bolstered by law. One unprecedented and unexpected consequence was that the California Legislature asked the California Department of Fish and Wildlife (DFW) to administer a state-funded recovery program for these sheep. The first task completed by the Recovery Program was the creation of a small interagency team of scientists and stakeholders that drafted the Recovery Plan for Sierra Nevada Bighorn Sheep, eventually finalized by the U.S. Fish and Wildlife Service in 2007. This plan identifies key issues, sets recovery goals, and lists recommended recovery actions.
The total population of Sierra bighorn has shown a remarkable recovery since its low ebb of about 100 animals in 1995 to more than 600 in 2014, part of which can be attributed to recovery program actions. On this website we invite you to learn more about Sierra bighorn and conservation efforts on their behalf. In the following pages you will find information about the work of the Sierra Nevada Bighorn Sheep Foundation, the scientific research we support, and how you can help.