The California Department of Fish and Wildlife is trying to help Sierra Nevada bighorn sheep by transporting them into open territory—and it’s working. The population of this endangered subspecies of North American bighorn was down to as few as 100 individuals. Now it has increased to about 600, half its estimated historic level. California wildlife biologists are aiming to restore robust herds in 12 adjacent chunks of habitat. Instead of using captive-bred animals, it’s extracting wild sheep, mostly pregnant ewes, from healthy herds and using them to start or augment other herds.