Rambla Pacifico Street Reconstruction EIR Section 4.1 Biological Resources 4.1 BIOLOGICAL RESOURCES This section analyzes the proposed project’s impacts to biological resources. Both direct impacts associated with site development and indirect impacts to off-site biological resources are addressed. 4.1.1 Setting a. Regional Setting. The project site is located within the City of Malibu, Los Angeles County, California, in the southern portion of the Santa Monica Mountains of the greater South Coast Range. The Santa Monica Mountains consist of steeply sloping hills and narrow canyons ranging in elevation from zero feet above sea level, where the mountains meet the ocean, to over 3100 feet above sea level. The region is characterized by a Mediterranean climate with mild, wet winters and warm, dry summers. Precipitation falls primarily during the winter months and averages approximately 24 inches per year (Western Regional Climate Center, 2010). The project site, approximately 750 feet as the crow flies north of the Pacific Ocean, lies on a coastal bluff that is adjacent to the terminus end of the Las Flores Canyon Watershed. Las Flores Creek, which is bounded on the east by housing and on the west by Rambla Pacifico Street, carries runoff from one of the largest watersheds in the Santa Monica Mountains and provides sand for Las Flores Beach. The following analysis is based in part on a Biological Assessment performed by Forde Biological Consultants (FBC)(June 2007 and update dated November 2008, January 2010), which includes a rare plant survey conducted by Dr. Edith Read; a Protected Tree Report by FBC (November 2008); a Revegetation Plan for Lower Rambla Pacifico Street prepared by Dr. Edith Read (January 2010); a literature review concerning biological resources known to occur in the area; and review of aerial photography of the site. For purposes of this document, the “study area” shall be defined as the proposed alignment plus a 50-foot buffer as determined by Forde Biological Consultants. All biological reports can be found in Appendix B. b. Vegetation. Coastal sage scrub is the dominant habitat onsite. This habitat type most closely corresponds with Diegan Coastal Sage Scrub as defined by Holland (1986) and with the California Sagebrush series defined by Sawyer and Keeler-Wolf (1995). The majority of the study area is either disturbed or subject to fuel modification. Disturbed areas are either devoid of vegetation or are dominated by non-native species including, but not limited to, castor bean (Ricinus communis), mustard (Brassica sp.), giant reed (Arundo donax), myoporum (Myoporum sp.), Russian thistle (Salsola tragus), slender wild oat (Avena barbata), star thistle (Centaurea melitensis), spurge (Euphorbia sp.), and sweet fennel (Foeniculum vulgare). Landscape plants persist in areas surrounding previously occupied single-family residences and a stand of eucalyptus (Eucalyptus sp.) is located near the western end of the alignment. The California Invasive Plant Council describes a number of these non-natives as “aggressive invaders that displace natives and disrupt natural habitats.” Native species, including buckwheat (Eriogonum sp.), California sagebrush (Artemisia californica), California brickelbrush (Brickellia californica), coyote brush (Baccharis pilularis), giant wild rye (Leymus condensatus), goldenbush (Isocoma menziesii), golden-yarrow (Eriophyllum confertiflorum), laurel sumac (Malosma laurina), lemonadeberry (Rhus integrifolia), poison oak (Toxicodendron diversilobum), sunflower (Helianthus annuus), and sage (Salvia sp.), dominate City of Malibu 4.1-1 Rambla Pacifico Street Reconstruction EIR Section 4.1 Biological Resources areas east of the southern portion of Rambla Pacifico Street, where the proposed alignment exits the Rambla Pacifico Street easement, downslope toward the Rambla Pacifico Street easement. Native plants observed along the proposed alignment are common to coastal sage scrub communities of southern California. c. Wildlife. Birds observed or otherwise detected by FBC included Anna’s hummingbird (Calypte anna), Bewick’s wren (Thryomanes bewickii), blue-gray gnatcatcher (Polioptila caerulea), California quail (Callipepla californica), California thrasher (Toxostoma redivivum), California towhee (Pipilo crissalis), common bushtit (Psaltriparus minimus), house finch (Carpodacus mexicanus), lesser goldfinch (Carduelis psaltria), mourning dove (Zenaida macroura), northern mockingbird (Mimus polyglottos), roadrunner (Geococcyx californianus), western scrub jay (Aphelocoma californica), and wrentit (Chamaea fasciata). FBC also observed an American kestrel (Falco sparverius) and a red-tailed hawk (Buteo jamaicensis) fly over the area and observed a pellet of a barn owl (Tyto alba) or great horned owl (Bubo virginianus) below the stand of eucalyptus trees. Birds with the potential to occur include, but are not limited to, black phoebe (Sayornis nigricans), lesser goldfinch (Carduelis psaltria), lesser nighthawk (Chordeiles acutipennis), northern flicker (Colaptes auratus), ruby-crowned kinglet (Regulus calendula), sage sparrow (Amphispiza belli), spotted towhee (Pipilo maculates), and western kingbird (Tyrannus verticalis). FBC did not observe any mammals within the study area; however, evidence suggesting the presence of Audubon’s cottontail (Sylvilagus audubonii) or brush rabbit (Sylvilagus bachmani), California ground squirrel (Spermophilus beecheyi), coyote (Canis latrans), dusky-footed wood rat (Neotoma fuscipes), mule deer (Odocoileus hemionus), long-tailed weasel (Mustela frenata) and valley pocket gopher (Thomomys bottae) were observed. Mammals with the potential to occur include, but are not limited to, bobcat (Felis rufus), California mouse (Peromyscus californicus), California pocket mouse (Chaetodipus californicus), deer mouse (Peromyscus maniculatus), gray fox (Urocyon cinereoargenteus), Pacific kangaroo rat (Dipodomys agilis), raccoon (Procyon lotor), and striped skunk (Mephitis mephitis). Mountain lions (Panthera concolor) are known to range throughout the Santa Monica Mountains and may occur in the vicinity of the study area from time to time. Big brown bat (Eptesicus fuscus), California myotis (Myotis californicus), free-tailed bat (Tadarida brasiliensis), long-legged myotis (Myotis volans), western pipistrelle (Pipistrellus hesperus), western red bat (Lasiurus blossevillii), and small-footed myotis (Myotis ciliolabrum) may forage over the area; however, potential roost sites are absent within the proposed construction limits. Several other bat species may occur, particularly during spring and fall migration. Reptiles observed include side-blotched lizard (Uta stansburiana hesperis) and western fence lizard (Sceloporus occidentalis longipes). Reptiles with the potential to occur include, but are not limited to, California kingsnake (Lampropeltis getulus californiae), chaparral whipsnake (Masticophis lateralis lateralis), gopher snake (Pituophis catenifer catenifer), red coachwip (Masticophis flagellum piceus), southern alligator lizard (Elgaria multicarinata webbi), western blind snake (Leptotyphlops humilis humilis), western skink (Eumeces skiltonianus skiltonianus), western rattlesnake (Crotalus oreganus), and western ringneck snake (Diadophis punctatus modestus). Amphibians with potential to occur include pacific treefrog (Hyla regilla) and western toad (Bufo boreas). d. Wildlife Movement. Natural movement corridors and habitat linkages have been the focus of numerous studies intended to better understand relationships between large animal City of Malibu 4.1-2 Rambla Pacifico Street Reconstruction EIR Section 4.1 Biological Resources populations, open space reserves, and natural movement patterns. In general, it has been amply demonstrated that fragmentation of large habitat areas into small, isolated segments reduces biological diversity, eliminates disturbance-sensitive species, restricts genetic flow between populations of organisms, and may eventually lead to local extinctions of entire floral or faunal assemblages. Most land use planning guidelines now recognize the importance of protecting wildlife movement corridors, and seek to retain major linkages intact wherever possible. However, defining precise or comprehensively useful corridor alignments or specific spatial and resources requirements is still conjectural. Wildlife movement corridors can vary from narrow specific paths a few feet wide used by certain species to move from breeding areas to forage areas, to major corridors for population dispersal and migration with spans of hundreds of miles and at the scale of mountain ranges and valleys. Depending on the organism and its needs, movement corridors can either be continuous or discontinuous patches of suitable habitat. For fish migrating upstream, the habitat needs to be relatively continuous, whereas highly mobile species such as birds and large mammals can adequately move through discontinuous habitat. Las Flores Creek may serve as a wildlife movement corridor but is outside of the impact boundary and will not be affected by the proposed action. Though not a recognized movement corridor, the project site contains habitat that may be used by wildlife moving throughout the Las Flores Canyon. e. Regulatory Setting. Regulatory authority over biological resources is shared by federal, state, and local authorities under a variety of statutes and guidelines. Primary authority for general biological resources lies within the land use control and planning authority of