The Heath and Marjorie Angelo Coast Range Reserve protects 7,660 acres of the upper watershed of South Fork of the Eel River in Mendocino County for university-level teaching and research. The Angelo Coast Range Reserve was the first gift to The Nature Conservancy west of the Mississippi, and for many years, the largest (see site history). Today, it is one of 39 protected natural areas in the University of California Natural Reserve System, and is managed through the U.C. Berkeley campus.
Since Heath and Margorie Angelo protected their land in the 1930s, the population of California has increased over six-fold. The Angelo gift, along with the 17 sq. km Elder Creek basin (designated as an area of critical ecological concern by the Bureau of Land Management) together constitute one of the largest continuous tracts of undeveloped coastal conifer forest remaining in California. The reserve protects 5 km of the upper South Fork Eel River, four undisturbed tributary watersheds, mixed conifer-broad-leaf forests, meadows on river terraces, and bands of chaparral at higher elevations.