The preserve is located within a designated Globally Important Bird Area, a program of the National Audubon Society with its partner BirdLife International to identify and protect critical avian habitats.

The golden trout is being reviewed by United States Fish and Wildlife Service for listing under the Endangered Species Act.

The purchase was in part to mitigate for the flooding of the South Fork Wildlife Area from Lake Isabella during high water years and resulting loss of willow flycatcher habitat.

[11] On January 31, 2006, the purchase of 105 acres (0.42 km2) of the Alexander Ranch that flanks the South Fork Kern River was completed with funds from the Resources Legacy Foundation.

The Pond Ranch purchase added one-quarter mile of the South Fork Kern River frontage to the preserve[3] In addition to real estate purchases, the Audubon California organization continues to work with private land owners in the South Fork Valley on conservation issues.

Bruce Hafenfeld, of the California Cattlemen's Association, operates a family ranch raising commercial calves and cows on both private property and public lands on a federal grazing allotment.

The University of California, Santa Barbara's Biogeography Lab report describes the distribution of this type of riparian forest as "Formerly extensive along the major low-gradient (depositional) streams throughout the Great Valley, but [are] now reduced to scattered, isolated remnants or young stands because of flood control, water diversion, agricultural development, and urban expansion..."[16] Rare wildflowers include the alkali mariposa lily.

It is a perennial bulb that blooms in April and May, and is threatened by grazing, trampling, road construction, urbanization and horticultural collecting.

The federally listed endangered southwestern willow flycatcher has small populations in the preserve and is closely monitored by Audubon volunteers and staff.

The US Fish and Wildlife Service designated critical habitat for the southwestern willow flycatcher which includes 9.6 miles (15.4 km) of the South Fork Kern River and excludes Hafenfeld Ranch which has the conservation easement in place.

[21] The US Fish and Wildlife Service's 5-year review of least Bell's vireo, dated September 2006, attributes the primary cause of population declines to loss of riparian habitat in California.

Another threat listed by the review is from the brown-headed cowbird which lays its eggs in other birds' nests, called brood parasiteism.

[2][22] Common mammals include mule deer, coyote, dusky-footed woodrat, long-tailed weasel, California ground squirrel, American black bear, and bobcat.

Also found at the preserve is the Pacific pond turtle, a species of concern in California and listed as endangered in Washington state.

The South Fork Valley is unique in California, as three of the ten floristic provinces in the nation meet and overlap here.

[27] The San Emigdio blue butterfly is a species of concern due to its limited local range consisting of Southern California from Inyo County south through the Mojave Desert, San Joaquin Valley, Bouquet and Mint canyons of Los Angeles County.

[29] A resurvey of Grinnell's original route was begun by the museum to research, document and model changes in the distribution and habits of animal species in the timespan between the early 1900s and the current century.

The Kern River Valley area, called the Whitney transect, was studied in June and September 2008 and in May 2009 by the resurvey teams.

Parts of the resurvey of California are completed, including Yosemite National Park, and show changing trends in wildlife territory and range; some expanding, some contracting and some species moving to higher elevations.