Early settlers grazed cattle and sheep, but soon farming became the dominant activity in the valley. The Nature Conservancy of California acquired the initial preserve core of 834 acres in 1989. Since the original acquisitions, some parcels have been added on the east side of Highway 58. During the summer of 1997, the lands were transferred to the Center for Natural Lands Management. Other parcels within the Lokern Preserve-complex were acquired with funds from the California Energy Commission and money from different mitigation projects.
Rainfall is scant during normal years, averaging six inches per year.
The preserve's terrain consists of flat and gently rolling shrubland and grassland, occasionally bisected by shallow dry arroyos. Patches of non-native grassland are also present in the Preserve, decreasing the quality of habitat when the density of grass species increases. The animals include the San Joaquin kit fox, blunt-nosed leopard lizard, San Joaquin antelope ground squirrel, and giant and Tipton kangaroo rats. Kern mallow is also present there. Other species of interest include LeConte's thrasher, burrowing owl, coyote and various birds of prey.