Sierra Nevada bighorn sheep are the rarest mountain sheep in North America. After the population dropped to around 100 animals in 1995, this unique sub-species was listed as an endangered species. In the spring of 2015, these charismatic animals were released into the heart of Yosemite for the first time in over 100 years. View Yosemite Nature Notes Episode 27, a video produced by Steven M. Bumgardner, that covers the reintroduction