California montane chaparral and woodlands

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Big Sur montane chaparral and woodland habitat. @ C. Michael Hogan

The California montane chaparral and woodlands is a near coastal ecoregion in Southern California, USA. This ecoregion is disjunctive, with a major element in Southern California and another along the Monterey County coast. The California montane chaparral and woodlands ecoregion is classified as an element of the Mediterranean Forests, Woodlands and Scrub Biome.

The faunal diversity of this ecoregion is moderate, with a total of 347 vertebrates having been recorded here.The montane habitats of southern California share many species with the Sierra Nevada Mountain Range to the north and the lower-elevation mediterranean woodlands and chaparral. Their communities, however, are distinctive in structure and composition, in addition to supporting a number of endemic and relict species.

California montane chaparral and woodlands ecoregion. Source: WWF

The ecoregion encompasses most of the Transverse Range that includes the San Bernardino Mountains; San Gabriel Mountains; portions of the Santa Ynez and San Rafael Mountains; Topatopa Mountains; San Jacinto Mountains; the Tehachapi, Greenhorn, Piute, and Kiavah Mountains that extend roughly northeast-southwest from the southern Sierra Nevada; and the Santa Lucia Range (part of the Coast Range) that parallels the coast southward from Monterey Bay to Morro Bay. Several of the mountain ranges in this ecoregion are complex and high, with peaks ranging up to 3500 meters (m) elevation in the Transverse Range. Such topography creates conditions for a wide range of natural communities, ranging from chaparral to mixed-conifer forests and alpine habitats. The California montane chaparral and woodlands ecoregion is given the numerical designation NA1203 by the World Wildlife Fund.

Biological distinctiveness

The California montane chaparral and woodland ecoregion consists of a complex mosaic of [[coast]al] sage scrub, lower chaparral dominated by chamise, upper chaparral dominated by manzanita, desert chaparral, Piñon-juniper woodland, oak woodlands, closed-cone pine forests, yellow pine forests, sugar pine-white fir forests, lodgepole pine forests, and alpine habitats. The prevalence of drought-adapted scrub species in the flora of this ecoregion helps distinguish it from similar communities in the Sierras and other portions of northern California. Many of the shared Sierra Nevadan species typically are adapted to drier habitats in that ecoregion, Jeffrey Pine (Pinus jeffreyi) being a good example. There are a number of special status organisms that are found in this ecoregion, variously denoted as Near Threatened (NT), Vulnerable (VU), Endangered (EN), or Critically Endangered (CR).

Monterey Cypress at Point Lobos. @ C.Michael Hogan

Some coastal sage scrub occurs on the southern slopes of the Transverse Range, although Chamise (Adenostoma fasciculatum) chaparral and scrub oak chaparral cover most lower habitats. Higher up, cold chaparral dominated by manzanitas are interspersed with closed-cone pine forests, Coulter Pine (Pinus coulteri) woodlands, and endemic bigcone Douglas-fir (Pseudotsuga macrocarpa) communities. Oak species are an important component of many chaparral and forest communities throughout the ecoregion. Canyon Live Oak, Interior Live Oak, Tanbark Oak (not a true Quercus species), Engelmann Oak, Golden-cup Oak, and Scrub Oak are some examples. Mixed-conifer forests are found between 1371 to 2896 meters (4500 to 9500 feet) elevation with various combinations and dominance of incense cedar, sugar pine, and white fir, Jeffrey Pine, Ponderosa Pine, and mountain juniper. Subalpine forests consist of groves of Limber Pine (Pinus flexilis), lodgepole pine, and Jeffrey Pine. Very old individual trees are commonly observed in these relict subalpine forests. Within this zone are subalpine wet meadows, talus slope herbaceous communities, krumholz woodlands, and a few small aspen groves. Herbaceous and shrubby species are very diverse and share affinities with the Sierras, Mojave Desert, and coastal and interior chaparral and woodlands. Numerous endemic plant species occur in many different communities.

In addition to these general vegetation patterns, this ecoregion is noted for a variety of ecologic islands, communities with specialized conditions that are widely scattered and isolated and typically harbor endemic and relict species. Examples include two localities of Knobcone Pine (Pinus attenuata) on serpentine soils, scattered vernal pools with a number of endemic and relict species, and isolated populations of one of North America’s most diverse cypress floras, including the rare Gowen Cypress (Cupressus goveniana goveniana) restricted to two sites on acidic soils in the northern Santa Lucia Range, Monterey Cypress (Cupressus macrocarpa) found only at two [[coast]al] localities near Monterey Bay, and Sargent Cypress (Callitropsis sargentii LR/LC) restricted to serpentine outcrops. Monterey Pine (Pinus radiata) is also restricted to three coastal sites near Monterey Bay. The ecoregion supports eight endemic conifer species, the highest number for any ecoregion in the USA and Canada along with the Northern California coastal forest ecoregion.

The Santa Lucia Range supports scattered populations of redwoods limited to fog-inundated [[coast]al] valleys. Coast Live Oak and Madrone form coastal evergreen communities intermixed with coastal sage and chamise chaparral. At higher elevations, one finds Tanbark Oak and Canyon Live Oak woodlands eventually grading into forests of Ponderosa Pine, sugar pine, Jeffrey pine, Coulter Pine, and serpentine-associated Knobcone Pine. The range also harbors the unusual and endemic Santa Lucia or bristlecone fir (Abies bracteata) between 610 and 1525 m (2000 and 5000 ft) elevation.

Mammals

Botta's Pocket Gopher. Source: Friends of Five Creeks/EoL

The ecoregion is also home to a few endemic or near-endemic vertebrates, such as the White-eared Pocket Mouse (Perognathus alticolus EN), a mammal known only to two disjunct mountain ranges in southern California: San Bernardino Mountains in San Bernardino County (ssp. alticolus), and the Tehachapi Mountains, in Kern, Ventura, and Los Angeles counties. The near-endemic fossorialan animal that engages in burrowing or living underground Agile Kangaroo Rat (Dipodomys agilis) is found in the southern disjunctive unit of the ecoregion, and is known only to the Los Angeles Basin and foothills of San Gabriel and San Bernardino mountains in Ventura, Los Angeles, and Riverside counties north to Santa Barbara County and through the southern Sierra Nevada, including Mount Pinos, Tehachapi and San Gabriel mountains, and northern San Fernando Valley. Non-endemic mammals found in the ecoregion include Botta's Pocket Gopher (Thomomys bottae) and Trowbridge's Shrew (Sorex trowbridgii). Some larger vertebrate predators can be found in the ecoregion, including Puma (Puma concolor), Bobcat (Lynx rufus), Coyote (Canis latrans), and Ringtails (Bassariscus astutus).

Amphibians

Monterey Ensatina. Source: Todd Battey/ CalPhotos/EoL

The ecoregion boasts five endemic and near-endemic amphibians, largely Plethodontid salamanders. Some specific salamander taxa found here are the endemic Tehachapi Slender Salamander (Batrachoseps stebbinsi VU), known from isolated sites in the Caliente Creek drainage, Piute Mountains, and Kern County, California along with scattered populations in the Tehachapi Mountains to Fort Tejon, Kern County; the near-endemic Blackbelly Slender Salamander (Batrachoseps nigriventris); the Monterey Ensatina (Ensatina eschscholtzii); the Channel Islands Slender Salamander (Batrachoseps pacificus), endemic to a narrow range restricted solely on Anacapa, Santa Cruz, Santa Rosa, and San Miguel islands; and the Arboreal Salamander (Aneides lugubris), found only in California and Baja California. A newt found here is the Coast Range Newt (Taricha torosa). Anuran taxa in the ecoregion include theFoothill Yellow-legged Frog (Rana boylii NT); the Southern Mountain Yellow-legged Frog (Rana muscosa EN), a California endemic occurring in several disjunctive populations; and the Northern Red-legged Frog (Rana aurora).

Reptiles

Side-blotched Garter Snake. Source: Andrew Borcher /Calphotos/EoL

The California montane chaparral and woodlands ecoregions contains a number of reptiles such as the Coast Horned Lizard (Phrynosoma coronatum), who ranges from Northern California to Baja California. Also found here is the Sagebrush Lizard (Sceloporus graciosus); the Western Fence Lizard (Sceloporus occidentalis); the Southern Alligator Lizard (Elgaria multicarinata); and the Side-blotched Lizard (Uta stansburiana). The Two-striped Garter Snake (Thamnophis hammondii) is a restricted range reptile found near-coastally from Monterey County, California southward to Baja California.

Birdlife

The California Condor once inhabited much of the ecoregion, with the western Transverse Range acting today as a refuge for the last wild population, after considerable conservation efforts, especially in the Los Padres National Forest. The Heermann's Gull (Larus heermanni NT) is found in coastal areas of the ecoregion.

Arthropods

Winter aggregations of Monarch Butterflies occur at several localities near Monterey Bay and southward along the coast, with production of prolific nests in areas such as Pacific Grove and Carmel.

Fire regime characteristics

California montane chaparral and woodlands historically have their ecology strongly controlled by natural fires. It is also thought that during the Holocene, Native Americans may have used fire as a means of maximizing game productivity. In any case, prior to the early 1900s the records of fire are not consistent, such that calculations of return frequency is difficult. It is known that the intervention of man starting in the early 20th century has had a profound effect upon the ecology of these systems. While the introduction of aggressive fire suppression was well meaning, it now persists in an ever heightened manner due to the desire to protect human lives and buildings that have intruded into this ecosystem. The issue is even more complex in this ecoregion, where the increasing presence of man has induced more human-caused fire incidents, and the rugged complex terrain makes control of wildfires much more difficult than in ordinary terrain.

The problem with heightened fire suppression is twofold. Firstly the ecosystem dynamics are destabilized, since normal succession involves periodic fires, likely on the order of every thirty to fifty years. This destabilization causes changes in species distribution, intrudes on decomposition cycles and alters age distribution and recruitment patterns of flora. For example, fire suppression in many California montane chaparral and woodlands communities in Northern California has led to the advance and dominance of conifers in many of these ecosystems which have been historically dominated by oaks. In extreme cases, large areas have been altered from productive habitats with diverse flora and fauna, to become dense stands of conifer with depauperate forest floors.

The second major consequence of fire suppression is buildup of excessive debris, chiefly from desiccated or dead chaparral species. Thus when a fire arises, it burns hotter and travels more swiftly than historic natural fire regimes. Not only is this an adverse consequence with respect to ultimate control and protection of human lives, but the ecological alteration covers a much wider area than typical historic fires. This outcome has consequences of broader scale erosion and more extensive habitat fragmentation than would historically be the case.

Conservation status

Habitat loss and degradation

California condor (Gymnogyps californianus). Source: Jeff Foot/WWF

Approximately thirty percent of the ecoregion is supports relatively intact habitat, with the caveat that virtually all bunchgrass elements have been replaced by introduced annual grasses and fire suppression, grazing, and loss of riparian and aquatic habitats are a major problem everywhere.

Remaining blocks of intact habitat

The Ventana Wilderness area in the Santa Lucia Range and the Ventura region of the Transverse Range have some of the larger intact habitat blocks. The northern extension of the [[ecoregion]s] towards the Sierra Nevada has some large blocks, although much of this region is significantly impacted by grazing, cement mining, cotton, and windmill farms. Some larger, more intact blocks occur on Forest Service lands and the San Emigidio Ranch, recently purchased by the Wildlands Conservancy. The few blocks of conifer forests on the mountain peaks of the Transverse Range are all disturbed by development, grazing, logging, and fire suppression. Most of the designated wilderness areas are small and heavily used. Some of the best examples of native blue and valley oak woodlands occur in the inland valleys of the northern Santa Lucia Range, near Hunter-Leggett and the Ventana Wilderness.

Degree of fragmentation

The southern part of the ecoregion is heavily incised with roadways, and valley bottoms are largely developed. Fragmentation and isolation of intactThe condition of an ecological habitat being an undisturbed or natural environment habitat blocks is relatively high.

Degree of protection

Much of the ecoregion falls within the Los Padres National Forest. The forests and chaparral of this National Forest suffer from intensive logging of low-productivity ecosystems, overgrazing, air pollution, loss of aquatic habitats, heavy recreational use, and decades of fire suppression intervention by man.

Ecological threat profile

Pine Ridge, Carmel River Valley, California, USA. Photograph: Jeffrey Zimmerman

Fire suppression is a severe problem throughout the ecoregion, allowing fuel loads to build up and increase the probability of [[ecologic]ally] devastating hot fires. Few large predators remain due to centuries of hunting and predator control. The high densities of deer, rodents, and other herbivores that has resulted from predator extirpation contribute to intensive grazing and seed predation. This effect results in dramatic changes to plant and animal communities throughout the ecoregion. Many springs, streams, rivers, and other aquatic habitats have been highly disturbed through land development, overgrazing, sedimentation, [[introduced] species] (18% of the flora), and water diversions. Extensive development around lakes and streams for resorts and vacation homes has altered many montane aquatic systems. The wide range of terrestrial species that depend upon critical water resources to survive, such as amphibians, have been severely impacted by the loss and alteration of aquatic habitats. High-impact recreational activities, such as off-road vehicles and hunting, cause significant damage of plant communities and mortality and disturbance of wildlife.

Mixed conifer and closed-cone pine forests are heavily impacted by air pollution from urban centers. Ozone from smog causes Ponderosa Pine and other species of conifer, shrubs, and lichen to weaken and die.

Suite of priority activities to enhance biodiversity conservation

  • Restore fire events to frequencies and intensities within their natural range of variation through management prescriptions such as controlled burns and fuel reduction (not salvage logging).
  • Strictly protect ecologic islands and populations of rare species such as Gowen cypress and knobcone pine forests, vernal pools, and bigcone Douglas-fir and Santa Lucia fir groves. For example, strong protection needs to be given to Huckleberry Hill and its environs near Monterey to conserve several rare tree species.
  • Protect the last intactThe condition of an ecological habitat being an undisturbed or natural environment blocks of foothill oak woodlands, a habitat type severely threatened throughout most of its range.
  • Prohibit off-road vehicle use and overgrazing in fragile and rare serpentine plant communities.
  • Prohibit further cutting of the last remaining groves and trees used by overwintering monarchs. These sites may experience rare environmental conditions that are necessary for the butterflies to survive. Some municipal governments near Monterey Bay have voted to allow cutting of some of the butterfly trees for development, showing a disregard for the global rarity of this phenomenon or the fragile nature of the scattered populations. Multiple butterfly sites may be necessary to allow long-term persistence of the butterflies in the face of natural weather events.
  • The U.S. Forest Service must reduce timber harvest in these habitats characterized by low productivity and which experience significant periods of drought. Overgrazing and continued destruction of riparian and aquatic habitats should be curtailed on both federal and private lands.
  • Air pollution is a significant problem, and continuing reduction in smog from stationary and non-point emissions from Los Angeles and environs is a worthwhile goal.

Conservation Partners

  • California Native Plant Society
  • The Nature Conservancy of California
  • U.S. Fish and Wildlife Service
  • U.S. Forest Service

Neighboring ecoregions

References and additional information

  • Taylor H. Ricketts. 1999. Terrestrial ecoregions of North America: a conservation assessment. Island Press. 485 pages
  • Michael G.Barbour, Todd Keeler-Wolf, Allan A.Schoenherr. 2007. Terrestrial vegetation of California. University of California Press. 712 pages
  • C. Michael Hogan & Michael P. Frankis., Monterey Cypress: Cupressus macrocarpa, iGoTerra.com, ed. N. Stromberg
  • Noel Snyder and Helen Snyder. 2000. The California Condor: A Saga of Natural History & Conservation. San Diego, California: Academic Press. ISBN 0-12-654005-5.
  • Neil G.Sugihara. 2006. Fire in California's ecosystems. University of California Press. 596 pages
Disclaimer: This article contains some information that was originally published by the World Wildlife Fund. Authors for the Encyclopedia of Earth have edited its content and added new information. The use of information from the World Wildlife Fund should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.

Citation

Hogan, C., & Fund, W. (2014). California montane chaparral and woodlands. Retrieved from http://editors.eol.org/eoearth/wiki/California_montane_chaparral_and_woodlands