We need those wild places where we can study nature firsthand; places where all the intricacy and marvel of the natural world is intact. Everywhere, including California, those places are becoming fewer - and more precious. 

- Kenneth S. Norris, Founder of the UC Natural Reserve System

The Stunt Ranch Santa Monica Mountains Reserve lies within the Cold Creek watershed, perhaps the best preserved and most biologically diverse watershed area within the Santa Monica Mountains. Cold Creek itself, which flows through Stunt Ranch, has its origin on the north face of 855-meter (2,805-foot) Saddle Peak, one of the highest points in the Santa Monica Mountains. Cold Creek flows continuously throughout the year, even in dry years, although the highly variable rainfall regime of coastal Southern California strongly affects the level of flow. This permanent water flow, rare in the Santa Monica Mountains, is critical for the maintenance of a number of rare species. Smaller tributaries of Cold Creek flow out of the core area of Stunt Ranch Reserve, providing a well-developed corridor of riparian habitat.

Rainfall records for the upper elevations of the Santa Monica Mountains are not extensive, but it is estimated that Stunt Ranch receives a mean annual rainfall of about 60 centimeters (23.4 inches). This average value, however, obscures the extreme variability of rainfall between drought and flood years. In addition, rain in this region may fall with remarkable intensity for brief periods. The rainfall for the 2008-2009 winter season was just under 18.25 inches; about 70% of normal.

Extreme summer temperatures may occasionally reach 111deg F (40deg C) or higher. In general, however, temperature conditions are moderated by the close proximity of the Pacific Ocean. Frosts occur occasionally in winter.

INVENTORY

In 2008 the Reserve participated in the BioBlitz, a 24-hour inventory of plant/animals species in the Santa Monica Mountains sponsored by the National Geographic and the Santa Monica Mountains National Recreation Area. The number of species found totaled 1,732. Most of the these species can be found in/around the Stunt Ranch Reserve. The results are as follows: 50 algae, 5 amphibians, 627 arthropods, 132 birds, 33 fish, 4 fungi, 5 lichen, 26 mammals, 168 marine invertebrates, 5 other invertebrates, 655 plants, 18 reptiles, 3 tardigrades, and 1 unidentified species

The core reserve area of Stunt Ranch encompasses a mosaic of chaparral, live-oak woodland, riparian, and grassland communities. The chaparral community on north-facing slopes is largely dominated by scrub oak (Quercus berberidifolia), with a diverse mixture of other shrub species. Extensive areas of the reserve are dry, south-facing slopes dominated by Ceanothus megacarpus, chamise (Adenostoma fasciculatum), and laurel sumac (Malosma laurina). Adjacent areas of protected lands support other chaparral communities with diverse shrub species, including redshank (Adenostoma sparsifolium).

Coast live oak (Quercus agrifolia) is the primary dominant of the oak woodland community. Riparian communities are particularly well developed, both on small tributary streams and along Cold Creek. The dominant woody species in the riparian zone are coast live oak, sycamore (Platanus racemosa), California bay (Umbellularia california), and willows (Salix spp.). Herbaceous riparian species include the relatively uncommon stream orchid (Epipactis gigantea).

Ethel Stunt Oak Tree

The "matriarch" of the coast live oak woodland community at Stunt Ranch is named for the matriarch of the Stunt Family, Ethel Stunt. It is estimated that this majestic tree is between 500 to 1000 years old, was central to many Chumash/Gabrielino ceremonies, and shaded the original Stunt homestead cabin. The Ethel Stunt oak tree has also served as creative inspiration to the poets, artists, and photographers who have visited Stunt Ranch. Some of her branches and part of her canopy burned in the 1993 Malibu fire, but the Ethel Stunt oak, like most of the oaks on the Stunt Ranch Reserve, was not seriously damaged by the wildfire.

Both native and secondary grasslands are present on Stunt Ranch. While European annual grasses are the dominant species in these areas, good local populations of native bunchgrasses occur as well. A rare member of the sunflower family, Pentachaeta lyonii, a state-listed endangered species, is also present. Overall, more than 300 species of vascular plants have been reported for the Cold Creek watershed.

Vertebrate diversity is also high, providing almost a complete cross-section of the vertebrate faunas of the Santa Monica Mountains. Bird species are particularly abundant because of the mosaic of habitat types and the seasonal presence of migratory species. The riparian corridors are especially rich, supporting excellent populations of birds and amphibians. The Stunt Ranch fauna also includes the San Diego horned lizard and San Diego Mountain kingsnake, both species of special concern to the California Department of Fish and Game.

All of Stunt Ranch burned in the extensive Malibu/Topanga Fire of November 1993. Chaparral and grassland communities burned to the ground in the very hot fire, but shrubs resprouted from root crowns and seedlings of reseeding chaparral specialists are becoming established. Oaks in the woodland community were largely spared serious damage and also resprouted new canopy leaves. Only in the tributary riparian areas on the slopes of Stunt Ranch did the oaks receive extremely high temperatures and extensive charring of their trunks. These oaks resprouted slowly from epicormic shoots. The larger riparian areas along Cold Creek were spared the primary fire intensity, because of their topographic position, and these returned rapidly to normal form.