A transplanted bighorn sheep herd at the eastern edge of this national park produced eight lambs this spring, raising optimism about the herd's ability to survive in fresh surroundings.
Twenty-seven animals were separated from a herd south of Bishop and released in Lee Vining Canyon near Mono Lake in March, but trackers found that seven of them died.
Jeff Keay, a Yosemite wildlife biologist, believes the oldest and youngest sheep were the ones that died within two weeks of the transfer.
Two rams spotted last week in the park are moving to higher slopes as snow melts, an annual process that shows the sheep are adjusting to their new range, Keay said this week.
The majestic bighorns, which once roamed across much of the eastern Sierra Nevada, were declared extinct in Yosemite in 1914. Creation of the new herd is part of an effort by public agencies and wildlife groups to restore the animals to their native territory.