Appendix B: Biotic Resources. B.1 Plants B.2 Wildlife

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B.1 Plants

B.2 Wildlife

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B.1 Plants

Ap pe nd ix B : B io tic R es ou rc es

The Los Angeles region is rich in natural resources. Lying between the tall peaks of the San Gabriel Mountains and the Pacific Ocean, the area’s plant and wildlife communities are as diverse as its topography. The region’s Mediterranean-type climate creates not only cool, moist areas in the coastal canyons but also more semi-arid and dry conditions inland. Plant species range from water-needy riparian trees such as native willows and California sycamore (Platanus racemosa) to the more drought-tolerant species such as those found within the chaparral or coastal sage scrub communities (see Figure B.1-1, Sycamore Tree along the San Gabriel Foothills). Wildlife dependent on these plants are equally as varied. The region is home to seven species of hawks, eight species of owls, peregrin falcons, golden eagles white-tailed kites (Santa Monica Mountains Conservancy 2008)

and other avian species.

John T. Lyle, in his book Design for Human Ecosystems, calls for a method of land-use planning that enables natural and human systems to co-exist. The Emerald Horseshoe Concept Plan is based

on ecosystematic design, which may help explain why project area plants and wildlife were examined with such specificity (Lyle 1999). In addition, the Los Angeles Region, with its elevated level of biodiversity lying adjacent to a complex urban infrastructure, offers a prime area to focus conservation and preservation areas.

Historical Plant Communities

The pre-development landscape was much different from what exists in the Emerald Horseshoe project area today. In the upper watersheds, the majority of the land was covered with shrub-dominated chaparral, patches of mixed hardwood/conifer woodlands, and strips of riparian vegetation along the watercourses (United States Army Corp of Engineers 2005). On the south-facing slopes of the foothills, a variety of shrub communities existed, such as Coastal Sage Scrub and Chaparral. On the shadier slopes and along the canyon floors, Oak and Walnut Woodlands flourished. In some foothill areas, near where the Arroyo Seco and Eaton Wash exited the mountains, alluvial fan sage scrub dominated, supported by the periodic flooding of the watercourses. Down in the valley, grasslands made up of perennial bunchgrasses, annual grasses, and herbs thrived. Alder, willow, and sycamore trees once stood along the banks of the Arroyo Seco and Eaton Wash. Near the confluence of the Los Angeles River and the Arroyo Seco, Southern California Black Walnut Woodlands once prevailed. This plant community is currently in decline throughout its Southern California range. (Arroyo Seco Foundation 200) (Figure B.1-2, Historical Plant Communities).

Existing Vegetation Locations

Today, development and ornamental landscapes have taken over almost the entire project area allowing ruderal non-native species to thrive, resulting in isolated patches of native vegetation that was once substantial habitat (City of Pasadena 200). Along the Arroyo Seco, stands of California black walnut (Juglans californica) still remain, although patchy and disconnected. Non-native invasive species make their way up the length of the river; their growth aided by the Figure B.1-1, Sycamore Tree along the San Gabriel Foothills

Sour ce: J ennif er M itamura 2008 Ap pe nd ix B : B io tic R es ou rc es

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continual disruption of the urban environment such as increased nitrogen deposition, air pollution, and ornamental planting. Closer to the mountains, the habitat begins to diversify and birchleaf mountain mahogany (Cercocarpus betuloides), California sagebrush (Artemisia californica), coast live oak (Quercus agrifolia), and scrub oak (Quercus berberidifolia) appear. The trapped water behind Devil’s Gate Dam feeds riparian-mixed hardwood species such as California sycamore (Platanus racemosa) (Figure B.1-, Existing Vegetation Types, Arroyo Seco). Angeles National Forest, in the upper reaches of the project area, offers the most substantial source of continuous vegetation. The area along the Altadena Crest Trail holds significant stands of coast live oak, scrub oak, canyon live oak (Quercus chrysolepis), and various types of chaparral and sage scrub. As Eaton Wash surfaces at the eastern end of Altadena Crest Trail, California sycamores begin to emerge and make their way down the wash (Figure B.1-, Existing Vegetation Types, Altadena Crest Trail). The project area, as it runs along Eaton Wash, is devoid of much vegetation aside from non-native grasses, forbs, ornamental grasses, scrubs, and hardwood species. There are also various nurseries that lay on the western side of the wash (Figure B.1-5, Existing Vegetation Types, Eaton Wash).

Existing Plant Communities

There are nine plant communities within the Emerald Horseshoe project area. The diversity of these vegetation types is not only dependent on elevation, but soil type and precipitation as well (see Figure B.1-6, Plant Communities Profile).

Bigcone Spruce-Canyon Oak Forest

Bigcone Spruce-Canyon Oak Forest is found in the upper reaches of the watershed where annual rainfall is high. This plant community is dominated by the bigcone spruce (Pseudotsuga macrocarpa) with a subcanopy of canyon oak (Quercus chrysolepis). Shrubs are infrequent within this community and the ground layer is typically sparse. The continuous canopy of this plant community is helpful in slowing and filtering rainfall. Within a chaparral matrix, as that found along the Altadena Crest Trail, stands of Bigcone Spruce-Canyon Oak Forest Figure B.1-2, Historical Plant Communities

Arroy o Seco

Ea_to

n W

as_h

Altadena Cres_{t Tra}

il

Coast Live Oak, Cultivated Riparian Black Sage, California Sage,

Chamise, Scrub Oak Douglas Fir

Sour ce: W ieslander 1900 Scale: NTS _N Grass Project Area

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B.1 Plants

Figure B.1-5, Existing Vegetation Types, Eaton Wash

Arro_yo

Se_co

Eaton

Wash

Figure B.1-3, Existing Vegetation Types, Arroyo Seco

Annual Grasses/ Forbes

Agriculture _{California Sagebrush}

Baccharis

California Sycamore

Barren/ Rocks

California Walnut

Bigcone Douglas Fir

Canyon Live Oak

0 1 2 Miles 0 0.5 1 Miles 0 1 2 Miles

Data fr

om: FRAP 1997

Figure B.1-4, Existing Vegetation Types, Altadena Crest Trail

Coast Live Oak

Ceanothus Mixed Chaparral

Rivers & Tributaries Scrub Oak

Non-Native Ornamental

Soft Scrub Mixed Chaparral Lower Mountane Mixed Chaparral

Sumac Scrub

Riparian Mixed Hardwood

Urban Water

Upper Montane Mixed Chaparral Perennial Grass

Mixed Conifer

Interior Mixed Hardwood

California Bay Eucalyptus

Riversidean Alluvial Fan Sage Scrub

Buckwheat Coastal Cactus

Birchleaf Mountain Mahogany

Project Area Ea to n W ash Alh am bra_W ash Ru bio_W ash Arc ad ia W ash Rio Hond o Los_A ng eles R ive_r Arroy o Seco Data fr om: FRAP 1997 Data fr om: FRAP 1997 N N N

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remain small, making it a key plant community to focus conservation and restoration efforts (see Figure B.1-, Existing Vegetation Types, Altadena Crest Trail) (Sawyer, Keeler-Wolf 1995, City of Pasadena 200, Sapphos Environmental 2006, Keeley 2002).

Coast Live Oak Woodland

On the shadier slopes and interior canyons Coast Live Oak Woodlands flourish. Coast live oak (Quercus agrifolia) is often the sole or dominant tree species in the canopy, which can be contiguous, irregular, or

open depending on the density of the other species within the community such as coast live oak, bigleaf maple (Acer macrophyllum), or California bay laurel (Umbellularia californica). Coast Live Oak Woodlands mix with Coastal Sage Scrub and Chaparral on drier sites, and are typically found on steep slopes or raised stream banks and terraces (see Figure B.1-, Existing Vegetation Types, Arroyo Seco and Figure B.1-, Existing Vegetation Types, Altadena Crest Trail). This plant community is home to a variety of wildlife species, including the Cooper’s hawk (Accipiter cooperii), one of the Emerald Horseshoe Design species (see Table B.1-1, Wildlife Design Species Matrix) (Sawyer, Keeler-Wolf 1995, City of Pasadena 200, Sapphos Environmental 2006, Keeley 2002).

Chamise Chaparral, Coastal Sage Scrub, Mule Fat Scrub

Further down slope, near streams, Chamise Chaparral turns into mixed Coastal Sage Scrub, and Mule Fat Scrub. Chaparral and Coastal Sage Scrub plant communities. These communities are a mixture of fire-adapted, hard-leaved, woody species found on dry, rocky, steep, south-facing slopes and ridges with shallow soils. Generally, shrubs are 6- to 10-feet tall. Along the Altadena Crest Trail, chamise (Adenostoma

South North

Snow Line

Granitic, Metamorphic Rocks Mixed with Sandy Loam, pH 5.2-5.5

Sandy Loam, pH 5.6-7.3 2,000’ 4,000’ 6,000’ 8,000’ 10,000’ 15”-30” Precipitation (inches/year) Elevation 25”-40” Clay to Granite pH up to 7.8 Young Alluvium and Silty Sand

Ruderal Nonnative Grasslands Bigcone Spruce Coast Live Oak Woodland

Southern Willow Scrub Mule Fat Scrub

Chamise Chaparral Riversidian Alluvial Fan Sage Scrub Sage Scrub Southern Sycamore-Alder Riparian Woodland 5-15” Soil

Data from: Sawyer and Keeler-Wolf 1997

Data fr om: Sa w yer and K eeler -W olf 1997

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B.1 Plants

fasciculatum), dominate the Chaparral plant community. Associated species include various salvias (Salvia mellifera, Salvia apiana), lemonade berry (Rhus integrifolia), and sugar bush (Rhus ovata) (see Figure B.1-, Existing Vegetation Types, Altadena Crest Trail).

Chaparral and Coastal Sage Scrub are two plant communities that are rapidly disappearing from the Southern California landscape. The San Gabriel Mountains and Angeles National Forest are the few remaining areas where these plant communities can still thrive. Their health means the success of many sensitive wildlife species, including the California gnatcatcher and Behr’s metalmark (see Table B.2-1, Wildlife Design Species Matrix) that rely on these communities.

Mule Fat Scrub, dominated by Mule fat, (Baccharis salicifolia), is similar to Chaparral and Coastal Sage Scrub plant communities; however, it is located further down slope along perennial and intermittent stream channels making it a more water-tolerant plant community (see Figure B.1-6, Plant Communities Profile). Mule Fat Scrub habitat needs seasonal flooding for its survival, hence the associated species, Arroyo willow (Salix lasiolepis), Mexican elderberry (Sambucus mexicana), and various sedges (Carex pansa, Carex spissa) (Sawyer, Keeler-Wolf 1995, City of Pasadena 200, Sapphos Environmental 2006, Keeley 2002). Southern Sycamore–Alder Riparian Woodlands, Southern Willow Scrub

At the base of the San Gabriel Mountains and throughout the valley riparian courses are dotted with water-loving Southern Sycamore– Alder Riparian Woodlands and Southern Willow Scrub. While these two plant communities house many of the same species, Southern Willow Scrub can be found at higher elevations than Southern Sycamore-Alder Riparian Woodlands because it requires more water. Southern Willow Scrub requires repeated flooding and is comprised of dense, broad-leaved, winter-deciduous riparian vegetation. This plant community is dominated by various willow species such as Arroyo willow (Salix lasiolepis), black willow (Salix gooddingii), red willow (Salix laevigata), shining willow (Salix lucida), and narrow leaved willow

(Salix exigua). Southern Willow Scrub lives in loose, sandy, or fine alluvium typically found in streams or along the banks. Stands of the community are dense, preventing a significant understory; however, in more open scrub habitats, forbs and grasses may grow. Like Mule Fat Scrub, Southern Willow Scrub is composed of individual species that may occur in wetlands, such as Western ragweed (Ambrosia psilostachya) and Mugwort (Artemisia douglasiana). These species have the ability to grow and reproduce in soils intermittently or continuously saturated with water (Sawyer, Keeler-Wolf 1995, City of Pasadena 200, Sapphos Environmental 2006, Keeley 2002).

Southern Sycamore-Alder Riparian Woodlands are dominated by white alder (Alnus rhombifolia) and Western sycamore (Platanus racemosa). This is a winter deciduous woodland with an average canopy of 115 feet. Trees are mostly scattered in thickets of hard-leaved and deciduous species and are present at elevations within the Altadena Crest Trail (see Figure B.1-6, Plant Communities Profile) (Sapphos Environmental 2006). Riparian plant communities, such as Southern Sycamore-Alder Riparian Woodland and Southern Willow Scrub are particularly important in Los Angeles due to their role in maintaining the health of the region’s waterways and aquatic species. Riparian plants help clean natural water systems and provide nesting environments for wildlife. Without these plant communities, the region’s natural hydrologic cycle will never be restored.

Riversidean Alluvial Fan Sage Scrub

Only remnants of the Riversidean Alluvial Fan Sage Scrub, which once dominated the alluvial fan terraces of the valley, remain. This is a dry or xeric plant community that can tolerate temporary inundation and uses coarse soils to store and release moisture slowly. This plant community, found in old and young alluvial fan terraces, developed as a result of water and sediment deposition that came down the mountains during rain events. Due to development and flood control measures, Riversidean Alluvial Fan Sage Scrub is considered sensitive habitat by the State of California. The City of Pasadena, in a master plan for the Arroyo Seco, noted that without the presence of Devil’s

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Gate Dam, Riversidean Alluvial Fan Sage Scrub would have spread across most of the area (see Figure B.1-, Existing Vegetation Types, Arroyo Seco ) (Sawyer, Keeler-Wolf 1995, City of Pasadena 200, Sapphos Environmental 2006, Keeley 2002).

Ruderal Vegetation

Just as development has led to the loss of Riversidean Alluvial Fan Sage Scrub habitat, it has also contributed to the ruderal vegetation so prevalent throughout the watershed today. Ruderal vegetation describes non-native plant species or weeds and includes areas impacted by agriculture, construction, and other development activities. Fire is another cause of ruderal vegetation, particularly in Chaparral and Coastal Sage Scrub habitats. Non-native grass and forb species are able to out-compete non-sprouting native shrubs when fire

occurs more frequently than

twice per decade (see Appendix D, Supplemental Research). Ruderal vegetation provides the lowest habitat value for wildlife and the least opportunity for biodiversity (Sawyer, Keeler-Wolf 1995, City of Pasadena 200, Sapphos Environmental 2006, Keeley 2002).

Selection of Design Plant Species

Figure B.1-7, Plant Design Species Selection Process demonstrates the process of selecting design plant species for the Emerald Horseshoe project area. The process began by examining the objectives as they relate to habitat. Species were considered based on their relationship to the nine project area plant communities, their classification by the

STATE

LISTED

FEDERALLY

LISTED

POTENTIAL TO EXIST

WITHIN SITE

CALIFORNIA NATIVE PLANT SOCIETY

OBJECTIVES

• Restore, preserve, and reconnect habitat_{• Preserve sensitive native species}

PLANT COMMUNITIES

Bigcone

Spruce-Canyon Oak Forest Coast Live Oak Coastal Sage Scrub Chamise Chaparral Mule Fat Scrub RiversideanAlluvial Fan Sage Scrub Ruderal Nonnative Grassland Southern Sycamore-Alder Riparian Woodland Southern Willow Scrub

INDICATOR SPECIES

DESIGN SPECIES

Braunton’s milk-vetch Astragalus brauntonii Nevin’s barberry Berberis nevinii

Canyon Live Oak Quercus chyrsolepis

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B.1 Plants

Ap pe nd ix B : B io tic R es ou rc es Braunton’s milk-vetch Astragalus brauntonii FE, CNPS 1B Moderate

Canyon Live Oak

Quercus chrysolepis Nevin’s barberry Berberis nevinii FE, SE, CNPS 1B Many-stemmed dudleya

Dudleya multicaulis CNPS 1B Moderate

Mesa horkelia

Horkelia cuneata ssp.

Puberula CNPS 1B Moderate

Plummer’s mariposa lily

Calochortus plummerae CNPS 1B Moderate

Robinson’s pepper-grass

Lepidium virginicum var. robinsonii

CNPS 1B Moderate

San Gabriel bedstraw

Galium grande CNPS 1B Moderate

Slender mariposa lily

Calochortus clavatus var. gracilis

CNPS 1B Low

Spotted Humboldt’s lily

Lilium humboldtii var.

ocellatum CNPS 4.2 Low Coastal Sage Scrub Southern Sycamore-Alder Riparian Woodland Ruderal Nonnative Grassland Mule Fat Scrub CNPS 1B Bigcone Spruce-Canyon Oak Forest Potential to exist on site Chamise Chaparral Coast Live Oak Moderate Riversidean Alluvial Fan Sage Scrub Special Status

Davidson’s bush mallow

Malacothamnus davidsonii Southern Willow Scrub Plant Species Moderate CNPS 4.2 Southern California Black Walnut Juglans californica Moderate Moderate

Table B.1-1, Plant Selection Matrix Design Species Additional Native Species

Correct Photo to come Data fr om: Sa w yer and K eeler -W olf 1995, Sapphos En vir onmental 2005

FE: Endangered under the federal Endangered Species Act; SE: Endangered by the State of California; CNPS 1B and 4.2: Rare, threatened, or endangered by the California Native Plant Society

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California Native Plant Society, and their listing as indicator species. Federally and state-listed species were also selected based on their potential to exist within the project area. Table B.1-1, Plant Selection Matrix illustrates where the four design species fall within each of the nine plant communities. It also shows each species’ potential to exist in the site area and what status (federal, state, or California Native Plant Society) each species holds. This matrix was utilized to determine which species would be focused on in the Emerald Horseshoe design. Design Species

Braunton’s milk-vetch, Astragalus brauntonii

Braunton’s milk-vetch is listed as endangered under the federal Endangered Species Act and as rare, threatened, or endangered by the California Native Plant Society. There are currently 16 existing locations of Braunton’s milk-vetch within Simi Hills of Ventura and Los Angeles counties, the Santa Monica Mountains, the San Gabriel Mountains, and the Santa Ana Mountains in Orange County. The species generally occurs below

2,100 feet in elevation on south-, west-, and east-facing slopes, in open chaparral. Braunton’s milk-vetch can also be found in disturbed locations such as burn areas, along fire roads, fuel breaks, and where some clearing has occurred and competition from non-native species is low. The species is a perennial member of the pea family. It blooms lilac flowers from March

to July and typically appears after a chaparral fire along with other native perennial forbs (Munz 197). The plant typically lasts several years before it is crowded out by other vegetation. Its seeds survive in the soil bank for several years and have a seed coat typical of many chaparral plants. This explains the species germination in

post-disturbance environments, such as fire, which interrupts the seed dormancy. The biggest threat to Braunton’s milk-vetch is the loss of native habitat. Disturbance caused by housing construction in the foothills and trampling by hikers, off-road vehicles, and equestrians contributes to this habitat loss. Changes in the natural fire cycle, and habitat fragmentation and degradation by invasive weeds also create conditions unsuitable for Braunton’s milk-vetch to thrive (Center for Plan Conservation 2008). The Southern California National Forests are currently generating models that depict suitable habitat for the species. These models will then be used to manage existing populations (CNDDB 2000).

Canyon Live Oak, Quercus chrysolepis

Canyon live oak is an indicator species in the Bigcone Spruce Canyon Oak Forest plant

community. The Canyon live oak is found from the Coast Ranges and Cascade Range of Oregon south through the Sierra Nevada in California and to Baja California, Mexico. The Canyon live oak is an evergreen species that varies in size and form depending on its location. In shady canyons, the species may reach 100 feet in height, while on exposed slopes it stays smaller and appears

shrubby. Forests dominated by Canyon live oaks provide habitat and food for a large variety of wildlife, including the Cooper’s hawk (Accipiter cooperii). The Canyon live oak is a particularly important species within the Emerald Horseshoe project area due to its high ecological and morphological diversity. The species’ occurrence throughout a wide range of elevations, topography, and vegetation types indicates its ecological variability (Thornburgh 2008).

Sour ce: J ennif er M itamura 2008 Sour ce: M ichael W . T una 2006

Figure B.1-8, Braunton’s milk-vetch

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B.1 Plants

Nevin’s barberry, Berberis nevinii

Nevin’s barberry is listed as endangered under the federal Endangered Species Act and the State of California, and rare, threatened, or endangered by the California Native Plant Society. Nevin’s barberry is currently scattered throughout Southern California from Los Angeles County, east to Riverside and San Bernardino counties. The species grows in sandy or gravelly soils on steep north-facing slopes or on low gradient south- facing washes within Alluvial Scrub, Coastal Sage Scrub, or Riparian Scrub or Woodland habitats.

Nevin’s barberry is a large shrub with blue-green, spiny pinnate leaves. Red edible berries and yellow flowers bloom March through April. The species status as a federally endangered species is largely due to habitat loss from agriculture, urban development, flood control, and stream channelization (Mistretta and Brown 1989). Cultivation of Nevin’s barberry on private property constitutes the majority of known occurrences of the species as it has proven to be tolerant of various soils and cultivation practices. The United States Forest Service staff in Angeles National Forest currently monitors the species; however, more surveys to locate suitable habitat throughout the project area should be conducted (CNDDB 2000).

Sour

ce: Stan Shebs 2007

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Ap pe nd ix A : B io tic R es ou rce s

B.2 Wildlife

Wildlife and their associated habitat play a vital role in the biological and ecological processes that are essential to our human lives. These key processes depend on numerous interactions between micro-organisms, plants, and animals. Wildlife species facilitate the processes of pollination, seed dispersal, germination, soil generation, nutrient cycling, predation, habitat maintenance, waste breakdown, and pest control.

Many unique animals, which help to conduct these processes on a local scale, are found in the Los Angeles Region. Sadly, Los Angelenos remain largely unaware of these species. Selecting key wildlife species for which to design would help to foster the education and protection of these native animals and their habitat.

Selection of Design Wildlife Species

Design wildlife species have been selected to ensure the preservation of those animals that are still present, despite their low numbers. Their success is a direct reflection of the ecological health of the entire region. Utilizing research garnered from the Green Visions Plan, and

the Fire and Resource Assessment Program, existing suitable habitat within the project area was determined for design wildlife species. As with many of the plant communities that once existed in the Los Angeles region, various species of wildlife that once thrived in the area such as grizzly bears (Ursus arctos horribilis) have been extirpated. Maintaining the health and wellbeing of existing wildlife in the project area is crucial to the success of the entire watershed.

The process for choosing wildlife began by looking at the project objectives. Next, the Green Visions Plan’s criterion for selecting design wildlife species was utilized. The Green Visions Plan offers an assessment of wildlife species, which includes the following nine categories (Martino et al. 2005):

• Sensitive—Is the species sensitive to human disturbance or is it human-tolerant?

• Connectivity—Is the species sensitive to the distance between habitat patches?

• Biodiversity—Is there evidence that the species is an indicator of biodiversity in its or another taxonomic group? • Rare—Is the species rare in the study area?

• Keystone—Is the species disproportionately important to its ecosystem relative to its abundance?

• Umbrella—Will protection of the species result in the protection of other species?

• Fragmentation—Is the species sensitive to the size of habitat fragments?

• Habitat quality—Is the species sensitive to degradation of habitat quality?

• Knowledge—Is there sufficient scientific knowledge about the species to use it effectively?

After consulting the Green Visions Plan, the project area’s nine plant communities and trophic structure were examined to determine which wildlife species to focus on (Figure B.2-2, Wildlife Design Species Selection Process). Figure B.2-1, Bobcat Sour ce: F lick r 2008

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B.2 Wildlife

Ap pe nd ix A : B io tic R es ou rc es Ap pe nd ix B : B io tic R es ou rc es

Figure B.2-2, Wildlife Design Species Selection Process

Cooper's Hawk

Accipiter cooperii

California Gnatcatcher

Polioptila californica

OBJECTIVES

• Restore, preserve, and reconnect habitat

_{• Preserve sensitive native species}

GREEN VISIONS

PLAN CRITERIA FOR

DESIGN SPECIES

Sensitive • Connectivity • Biodiversity Rare • Keystone • Umbrella • Fragment

Habitat Quality • Knowledge

PLANT

COMMUNITIES

_TROPHIC

STRUCTURE

Primary Consumers Secondary Consumers Tertiary Consumers

DESIGN SPECIES

Mountain Lion

Puma concolor

Unarmored Threespine Stickleback

Gasterosteus aculeatus williamsoni

Western Spadefoot Toad

Spea hammondii

Clemmys marmorata pallida

Southwestern Pond Turtle

Behr's Metalmark

Apodemia virgulti

Bigcone Spruce-Canyon Oak Forest

Coast Live Oak • Coastal Sage Scrub Chamise Chaparral • Mule Fat Scrub Riversidean Alluvial Fan Sage Scrub

Ruderal Nonnative Grassland

Southern Sycamore-Alder Riparian Woodland Southern Willow Scurb

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Ap pe nd ix A : B io tic R es ou rce s Ap pe nd ix B : B io tic R es ou rc es

The trophic structure reflects the relationship between the plant and animal species found within a patch of habitat. This cyclical feeding interaction includes predator-prey, parasite-host, and plant-herbivore relationships and demonstrates the potential for food competition. The trophic structure played an integral role in determining the design wildlife species for the Emerald Horseshoe project area (Figure B.2-, Trophic Structure).

The wildlife matrix illustrates how each of the seven design species fit into the selection criteria (see Table B.2-1, Wildlife Design Species Matrix). Once again, the relationship of these wildlife species to the nine project area plant communities was key. As the Emerald Horseshoe project seeks to restore, preserve, and reconnect habitat the mutually beneficial association of vegetation and wildlife could not be ignored.

Organic Matter

Adapted from: Steiner 2000

Producers

Primary Consumers

Secondary Consumers

Tertiary Consumers

Figure B.2-3, Trophic Structure

Adapt

ed fr

om: St

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B.2 Wildlife

Species/Criteria _{Sensitive Connectivity Biodiversity Rare Keystone Umbrella Fragmentation} HabitatQuality Knowledge Associated Plant Communities

Birds

Sage Scrub, Native Alluvial Fan Sage Scrub, Mixed Chaparral

Riparian Woodlands, Chaparral, Sage Scrub

Chaparral, Sage Scrub, Conifer Forest, Grassland

Data from: Cornell Lab of Orinthology 2003, Illinois Natural History Survey 2008, Martino et al 2005, Mock 2004 California Gnatcatcher

Polioptila californica

Dune, Grassland Burrowing Owl

Athene cunicularia

Deciduous, Mixed and Conifer Forests, Oak Woodlands Cooper’s Hawk Accipiter cooperii California Quail Callipepla californica Loggerhead Shrike Lanius ludovicianus

Chaparral, Sage Scrub Rufous-crowned

Sparrow

Aimophila ruficeps

Sea Sparrow

Amphispiza belli Chaparral, Sage Scrub

Western Meadowlark

Strunella neglecta Dune, Grassland

White-tailed kite

Elanus leucurus Grassland, Wetlands, Riparian Woodlands

Yellow-breasted Chat

Icteria virens Riparian Hardwood Forest

Table B.2-1, Wildlife Design Species Matrix

Data fr om: C or nell Lab of Or nithology 200 , I llinois Natural H ist or y Sur ve y 2008, M ar tino et al . 2005, M ock 200

Design Species Additional Native Species

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Species/ Criteria Sensitive Connectivity Biodiversity Rare Keystone Umbrella Fragmentation HabitatQuality Knowledge Associated Plant Communities

Mammals

Chaparral/ Sage Scrub, Conifer Forest, Riparian Hardwood Forest

Chaparral, Open Forest, Grassland

Grassland

Chaparral/ Sage Scrub, Conifer Forest, Dune, Grassland, Riparian Chaparral/ Sage Scrub, Conifer Forest, Grassland

Chaparral/ Sage Scrub, Conifer Forest, Dune, Riparian Hardwood Forest

Chaparral/ Sage Scrub, Conifer Forest, Riparian Hardwood Forest

Data from: Cornell Lab of Orinthology 2003, Illinois Natural History Survey 2008, Martino et al 2005, Mock 2004 Bobcat Lynx rufus California Meadow Vole Mycrtous californicus Coyote Canis latrans Grey Fox Urocyon cinereoargenteus Long-tailed Weasel Mustela frenata Mountain Lion Puma concolor

San Diego Black-Tailed Jackrabbit

Lepus californica

Table B.2-1, Wildlife Design Species Matrix (continued)

Data fr

om: M

ar

tino et al

. 2005

Design Species Additional Native Species Species of Consideration

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B.2 Wildlife

Species/ Criteria _{Sensitive Connectivity Biodiversity Rare Keystone Umbrella Fragmentation} HabitatQuality Knowledge Associated Plant Communities

Fish

Amphibians

Freshwater Streams Unarmored Threespine Stickleback Gasterosteus aculeatus williamsoni

Riparian Hardwood Forest, Chapparal, Sage Scrub, Conifer Forest, Grassland Coast Range Newt

Taricha torosa

Chaparral, Sage Scrub, Conifer Forest, Grassland

Reptiles

Invertebrates

Western Spadefoot Toad

Spea hammondii

Coast Horned Lizard

Phrynosoma coronatum

Native Alluvial Fan Sage Scrub, Chaparral, Sage Scrub Southwestern Pond Turtle Clemmys marmorata pallida

Riparian Hardwood Forest, Ponds, Marshes, Reservoirs, Shallow Wetlands

Behr’s Metalmark

Apodemia virgulti Chaparral, Sage Scrub

Arroyo Chub

Gila orcutti Freshwater Streams

Table B.2-1, Wildlife Design Species Matrix (continued)

Data fr

om: M

ar

tino et al

. 2005

Design Species Additional Native Species

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Ap pe nd ix A : B io tic R es ou rce s Ap pe nd ix B : B io tic R es ou rc es Sour ce:: F riends of Chollas Cr eek 0 4 8 Miles Existing Habitat

Figure B.2-5, California Gnatcatcher Existing Habitat

California Gnatcatcher,

Polioptila californica The California

gnatcatcher is a state and federally listed endangered species (see Figure B.2-, California Gnatcatcher). Relatively open sage scrub, native alluvial fan sage scrub, and

chaparral support this species. The gnatcatcher breeds from February to mid-June and lays 75 percent of its eggs between April and

May. For nest building, the gnatcatcher prefers the center of native shrubs such as California sagebrush (Artemisia californica), California buckwheat (Eriogonum fasciculatum), and Laurel sumac (Malosma laurina). Nest success is more likely in these interior areas as predation by cowbirds or feral or domestic cats is one of the main threats to the species. Habitat loss, degradation, and fragmentation are serious threats to the bird. The gnatcatcher was chosen as a design species for the Emerald Horseshoe Concept Plan due to its endangered status and its reliance on Coastal Sage Scrub. By choosing a species that requires a rapidly disappearing plant community for its survival, management efforts must preserve both the bird and its habitat type, fulfilling multiple project objectives. Management recommendations for the species include off-road monitoring in Coastal Sage Scrub habitats in coastal California (Atwood and Bontrager 2001, Grishaver et al. 1998, Mock 200) (Figure B.2-5, California Gnatcatcher Existing Habitat).

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Figure B.2-4, California Gnatcatcher

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B.2 Wildlife

Ap pe nd ix A : B io tic R es ou rc es Ap pe nd ix B : B io tic R es ou rc es Cooper’s Hawk, Accipiter cooperii The Cooper’s hawk lives in deciduous, mixed, and conifer forests, and oak woodlands (see Figure B.2-6, Cooper’s Hawk). Within the project area, the hawk is present throughout the upper watershed and sporadically down the Arroyo Seco.

The Cooper’s hawk depends on good habitat quality for its survival. During breeding season, between March and August with its peak in May through July, the species uses an open bowl of sticks in the main crotch of a tree to build its nest. While the Cooper’s hawk is becoming increasingly more common in suburban and urban areas, pesticides, degraded habitat, and collision with windows represent several threats to the species. Human activities also have an impact on raptor nests by physically harming or killing eggs, or altering habits. The Cooper’s hawk, as a raptor species, has an important role in the Emerald Horseshoe Concept Plan as it preys on the cowbirds that threaten the California gnatcatcher. Therefore, the success of the Cooper’s hawk may increase the potential success of the California gnatcatcher. Management

recommendations for the success of the Cooper’s hawk include creating a spatial and temporal buffer zone for nesting raptors. Median buffer zones should be 1,722 feet (525 meters) wide and should last from the arrival of the adult birds to the nesting area through the first few weeks of nesting development (Cornell Lab of Ornithology 200, Haiman 2006) (Figure B.2-7, Cooper’s Hawk Existing Habitat).

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Figure B.2-7, Cooper’s Hawk Existing Habitat

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Figure B.2-6, Cooper’s Hawk

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Bobcat, Felis rufus The bobcat lives in chaparral, sage, conifer forest, and riparian hardwood forest (see Figure B.2-8 Bobcat). This species breeds from February through March and builds its dens in the rock piles or broken rocky ledges of the San Gabriel Mountains. While the

bobcat is not commonly preyed upon, kittens may be taken by foxes, coyotes, mountain lions, or owls. The bobcat, along with the Cooper’s hawk, is one of the Emerald Horseshoe’s top predator design species, an indication of the cat’s significant role within the trophic structure. Threats to the species include habitat fragmentation and poor habitat quality, which explains its concentration in the upper watershed of Angeles National Forest. Bobcats have an important role in the Emerald Horseshoe Concept Plan as their habitat sensitivity, particularly in adult females, makes them an important species to monitor. Management recommendations for the bobcat include maintaining a mosaic of cover types in riparian areas and on preferred areas such as cliffs and rock outcroppings (Martino et al. 2005, United States Forest Service 2008)

(Figure B.2-9, Bobcat Existing Habitat). Existing Habitat ₀ ₄ _{8 Miles}

Figure B.2-9, Bobcat Existing Habitat

Sour ce: U .S. F ish and W ildlif e S er vice 2008 N Emerald Horseshoe Figure B.2-8, Bobcat

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B.2 Wildlife

Ap pe nd ix A : B io tic R es ou rc es Ap pe nd ix B : B io tic R es ou rc es Unarmored Threespine Stickleback, Gasterosteus aculeatus williamsoni

There is a lack of existing suitable habitat for the unarmored threespine stickleback within the Emerald Horseshoe project area (Figure B.2-10, Unarmored Threespine Stickleback) The

stickleback is a state and

federally listed endangered species extirpated from the Los Angeles River watershed in the 190s as a result of habitat contamination and loss (Figure B.2-11, Unarmored Threespine Stickleback Existing Habitat). The only existing suitable habitat in the region for the stickleback is a small segment of freshwater in the upper San Gabriel River, outside of the Emerald Horseshoe project area. The stickleback was chosen for the Emerald Horseshoe project due to its standing as an indicator of good hydrologic function, water quality, and its extremely sensitive nature (Martino et al. 2005).

The unarmed threespine stickleback breeds from April through July. The fish builds its nest from aquatic plants and algae in quiet, shallow water, weedy pools, and clear slow-moving streams. The species is a good indicator of water quality due to its need for clear slow-moving water, not a typical feature of existing, altered waterways of the Los Angeles region. In addition to poor water quality, threats to the species include exotic or introduced animal species that use the stickleback’s habitat. Management recommendations include monitoring of the unarmored threespine stickleback, and removal of exotic animal species and plant species (USGS 2001).

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No Existing Habitat

Figure B.2-11, Unarmored Threespine Stickleback Existing Habitat

Sour ce: A qua tic R esour ce Specialists 2008 N Emerald Horseshoe

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Ap pe nd ix A : B io tic R es ou rce s Ap pe nd ix B : B io tic R es ou rc es Western Spadefoot Toad, Spea hammondii The Western spadefoot toad lives in Coastal Sage Scrub, Chaparral, grasslands, and grasslands with vernal pools (see Figure B.2-12, Western Spadefoot

Toad). The species breeds during the winter and spring months, from January through May in these vernal pools, or other temporarily wet areas. This species has only sporadic suitable habitat in the Emerald Horseshoe project area mostly due to habitat loss by urban development and conversion of native habitats to agricultural lands. The toad was chosen for the Emerald Horseshoe project as the success of the species would indicate that lands were stable and undisturbed enough to support it (Martino et al. 2005, Toure 200) (Figure B.2-1, Western Spadefoot Toad Existing Habitat).

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Figure B.2-13, Western Spadefoot Toad Existing Habitat

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B.2 Wildlife

Ap pe nd ix A : B io tic R es ou rc es Ap pe nd ix B : B io tic R es ou rc es Southwestern Pond Turtle, Clemmys marmorata pallida The Southwestern pond turtle was chosen as a design species for the Emerald Horseshoe project because it, like so many other design species, lacks substantial habitat in the project area (see Figure B.2-1,

Southwestern Pond Turtle). The pond turtle relies on riparian hardwood forest, ponds, marshes, shallow wetlands and reservoirs, all of which have been significantly altered in the urban environment. The pond turtle has a linear, riparian home range and may act as an umbrella for other species requiring good habitat quality in close proximity to streams. The pond turtle, from May through July, oviposits in sunny upland habitats between 100 and 1,00 feet from freshwater. Focusing on the success of a riparian species, such as the Southwestern pond turtle, would ensure that the project, once implemented, would continue to maintain the health, size, and connectedness of its

waterways. Due to the pond turtle’s historical distribution in the Arroyo Seco subwatershed, habitat restoration opportunities may exist in upper watershed tributaries such as in Fern Canyon or Millard Canyon (Martino et al. 2005, United States Army Corp of Engineers 2005) (Figure B.2-15, Southwestern Pond Turtle Existing Habitat).

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Figure B.2-15, Southwestern Pond Turtle Existing Habitat

Sour ce: C alif or nia Tur tle and Tor toise Club N Emerald Horseshoe

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Ap pe nd ix A : B io tic R es ou rce s Ap pe nd ix B : B io tic R es ou rc es Behr’s Metalmark, Apodemia virgulti The Behr’s metalmark, a multi-colored butterfly, finds its home in the Chaparral and Sage Scrub of the San Gabriel Mountains (see Figure B.2-16, Behr’s Metalmark). The butterfly feeds on the nectar in California

buckwheat (Eriogonum fasciculatum) and is in decline due to the loss of its host plant to invasive weeds and urbanization. The butterfly breeds each year from March through September. It lays its eggs in groups of two to four on the lower leaves of its host plant. Behr’s metalmark was chosen as a design species due to its reliance on an important Coastal Sage Scrub plant, California buckwheat, and because of its place as a primary consumer within the trophic structure. Management recommendations for the species include habitat restoration and cultivation of California buckwheat (Martino et al. 2005) (Figure B.2-17, Behr’s Metalmark Existing Habitat).

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Figure B.2-17, Behr’s Metalmark Existing Habitat

Sour ce: F lick r 2008 N Emerald Horseshoe

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B.2 Wildlife

Ap pe nd ix A : B io tic R es ou rc es Ap pe nd ix B : B io tic R es ou rc es Sour ce: Enc yclopedia Br itannica Online 2007 0 4 8 Miles Existing Habitat

Mountain Lion Existing Habitat

Species of Consideration

The mountain lion is a special species of consideration for the Emerald Horseshoe project. While this species is prevalent in parts of the project area, it was not chosen as a design species due to its potentially dangerous interactions with people. In an effort to mitigate contact and conflict areas, the mountain lion’s particular needs must be addressed. The species is sensitive to habitat disturbance and fragmentation and requires large swathes of land for adequate range. For advantageous hunting, the lion uses shrub cover and rock outcroppings. Human development provides very low potential for suitable habitat. Some mountain lions, however, are adaptable to the urban environment. Emerald Horseshoe trails and recreation areas would avoid infringing on the mountain lion’s habitat and would in fact designate certain areas for no trail planning, leaving the mountain lion its fair share of the land. Finally, caution and educational signs would be located at access points along the Altadena Crest Trail to further alert people to the danger the mountain lion poses in these more remote areas (California Polytechnic University, Pomona 2006) (see Mountain Lion Existing Habitat).

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Mountain Lion

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