Results

The wildlife surveys conducted throughout the Cal Poly properties resulted in the detection of 32 mammalian species, 147 avian species and 9 amphibian and reptile species (Table 3). These surveys, although not all inclusive, provide a basis for rating each of the properties as being satisfactory in terms of the wildlife species it contains, or as having the potential to sustain additional species. This is especially true for mammals, reptiles and amphibians, which are more likely to be permanent residents since they do not have the same ability to move great distances as avian species. In the tables depicting mammalian species richness, numbers have been added in parentheses to indicate the number of species that were not detected during the surveys. This number indicates that due to the nature of the species, that is, more sedentary than avian species but less visible, it is probable that given the appropriate conditions within the habitat, the species will occur at the site. For a baseline analysis, these numbers provide us with an indication of the health of the habitat, with a lower number of undetected species being an indicator of healthier habitat.

A mammal survey was conducted by Cal Poly students David P. Domin and Niloufar C. Gary in 1998. The survey confirmed the presence of 18 different mammal species (Appendix A). Mammalian species not detected during the course of this survey are listed in Appendix B. Table 4 provides a summary of the results in terms of mammalian species richness by habitat type. The potential exists to increase the number of mammalian species in the various habitats of Cheda Ranch, especially the riparian and grassland areas. The low species richness in the agricultural fields is not unexpected due to the nature of the operations in those lands.

Table 3. List of birds, mammals, reptiles and amphibians detected throughout Cal Poly’s properties in San Luis Obispo County. Species are listed by common name in alphabetical order. (For a complete list of species in taxonomic order with scientific name, plese refer to the appendices.)

Avian Species

Acorn Woodpecker	Common Goldeneye	Mourning Dove	Western Bluebird
Allen's Hummingbird	Common Poorwill	N. Rough-winged Swallow	Western Kingbird
American Coot	Common Snipe	Northern Flicker	Western Kingbird
American Crow	Common Yellowthroat	Northern Harrier	Western Meadowlark
American Dipper	Cooper's Hawk	Northern Mockingbird	Western Screech-Owl
American Goldfinch	Costa's Hummingbird	Northern Shoveler	Western Scrub Jay
American Kestrel	Dark-eyed Junco	Nuttall's Woodpecker	Western Tanager
American Pipit	Double-crested Cormorant	Oak Titmouse	Western Wood-Pewee
American Robin	Downy Woodpecker	Orange-crowned Warbler	White-breasted Nuthatch
Anna's Hummbingbird	Eared Grebe	Pacific-slope Flycatcher	White-crowned Sparrow
Ash-throated Flycatcher	European Starling	Pied-billed Grebe	White-tailed Kite
Band-tailed Pigeon	Ferruginous Hawk	Prairie Falcon	White-throated Swift
Bank Swallow	Golden Eagle	Purple Finch	Wild Turkey
Barn Owl	Golden-crowned Sparrow	Red-necked Phalarope	Wilson's Phalarope
Barn Swallow	Grasshopper Sparrow	Red-shouldered Hawk	Wilson's Warbler
Belted Kingfisher	Great Blue Heron	Red-tailed Hawk	Wrentit
Bewick's Wren	Great Egret	Red-winged Blackbird	Yellow Warbler
Black Phoebe	Great Horned Owl	Ring-billed Gull	Yellow-billed Magpie
Black-chinned Sparrow	Greater White-fronted Goose	Ring-necked Duck	Yellow-breasted Chat
Black-crowned Night-Heron	Green Heron	Rock Dove	Yellow-headed Blackbird
Black-headed Grosbeak	Green-winged Teal	Rock Wren	Yellow-rumped Warbler
Blue Grosbeak	Hairy Woodpecker	Ruby-crowned Kinglet
Blue-gray Gnatcatcher	Heermann's Gull	Ruddy Duck
Brewer's Blackbird	Hermit Thrush	Rufous Hummingbird
Brown Creeper	Hooded Merganser	Rufous-crowned Sparrow
Brown-headed Cowbird	Hooded Oriole	Sanderling
Bufflehead	Horned Grebe	Savannah Sparrow
Bullock's Oriole	House Finch	Say's Phoebe
Bushtit	House Sparrow	Sharp-shinned Hawk
California Gull	House Sparrow	Short-billed Dowitcher
California Quail	House Wren	Solitary Vireo
California Thrasher	Hutton's Vireo	Song Sparrow
California Towhee	Killdeer	Spotted Sandpiper
Canada Goose	Lark Sparrow	Spotted Towhee
Caspian Tern	Lazuli Bunting	Steller's Jay
Cassin's Kingbird	Lesser Goldfinch	Swainson's Hawk
Cattle Egret	Loggerhead Shrike	Townsend's Warbler
Cedar Waxwing	Long-billed Curlew	Tree Swallow
Chesnut-backed Chickadee	Mallard	Tricolored Blackbird
Chipping Sparrow	Marsh Wren	Turkey Vulture
Cinnamon Teal	Merlin	Violet-green Swallow
Cliff Swallow	Mew Gull	Warbling Vireo

Table 3 (cont’d.). List of birds, mammals, reptiles and amphibians detected throughout Cal Poly’s properties in San Luis Obispo County. Species are listed by common name in alphabetical order. (For a complete list of species in taxonomic order with scientific name, plese refer to the appendices.)

Mammalian Species		Reptile & Amphibian Species

Badger	Domestic Cat	Ensatina
Black-tailed Deer	Dusky-footed Woodrat	California newt
Black-tailed Jackrabbit	Elk	California tree frog
Bobcat	Gray Fox	Side-blotched lizard
Botta's Pocket Gopher	House Mouse	Western skink
Broad-footed Mole	Mountain Lion	California legless lizard
Brush Mouse	Ornate Shrew	Striped racer
Brush Rabbit	Pinyon Mouse	Ringneck snake
California Ground Squirrel	Raccoon	Common garter snake
California Mouse	Roof Rat
California Pocket Mouse	Striped Skunk
California Vole	Trowbridge's Shrew
Coyote	Virginia Opossum
Deer Mouse	Western Gray Squirrel
Desert Cottontail	Western Harvest Mouse
Desert Woodrat	Western Spotted Skunk

An avian survey conducted by Amy Anderson (1998) resulted in the identification of 58 bird species (Appendix C). The majority of the bird species observed (53%) were within the riparian zone (Table 5). Although not the largest habitat type on the ranch, the riparian zone provides more cover and three dimensional habitat structure than any of the other three habitats, thus creating a more favorable environment for birds.

Mammal Species	Reservoir	Grassland	Buildings/ Urban	Riparian	Rock Outcrop	Fence Lines	Yucca Scrub	Coast Live Oak Woodland	Agricultural Field	Coastal Scrub	Chaparral
Marsupials	0 (1)		0 (1)	0 (1)
Insectivores	0 (1)	0 (1)		0 (2)
Lagomorphs		0 (2)		0 (1)	0 (1)				0 (2)
Squirrels	1 (0)	1 (0)	1 (0)						0 (1)
New World Mice	3 (0)	4 (0)	2 (0)	3 (0)	4 (0)				5 (0)
New World Rats	2 (0)	0 (1)		1 (0)	1 (0)				0 (1)
Old World Mice and Rats		0 (1)	0 (2)	0 (1)					0 (1)
Other Rodents	0 (0)	1 (0)	1 (0)						1 (0)
Carnivores	4 (2)	2 (2)	2 (2)	3 (4)	1 (3)				2 (3)
Ungulates	1 (0)	1 (0)	1 (0)	1 (0)	1 (0)				1 (0)
TOTAL SPECIES	11 (4)	9 (7)	7 (5)	8 (9)	7 (4)				9 (8)

Table 5. Avian diversity in Cheda Ranch. About one third of the species were detected in more than one habitat. The riparian corridor was found to be the most exclusive habitat with 15 species not found in any other habitat. The percent of total species indicates the percent of species detected in each of the habitats based on total number of species detected throughout the ranch.

At least eight plant communities cover parts of the Main Campus including: urban, agriculture, grassland, coast live oak woodland, riparian woodland, yucca scrub, coastal scrub and reservoirs. Like other parcels, the riparian woodland is an important habitat on campus because the water of the creeks is valuable to wildlife during the dry summers and when plants of other communities are dormant, riparian plants remain productive (Holland and Keil 1995). Dominant trees in the riparian woodland are sycamore (Platanus racemosa), black cottonwood (Populus balsamifera), arroyo willow (Salix lasiolepis), and California bay-laurel (Umbellularia californica). While sycamore trees are not a direct food source for wildlife (Martin et al. 1961), they are most valuable as a nesting site for cavity nesters. The high plant productivity in the riparian areas results in large numbers of invertebrates, which provide a food base for many animals, especially birds.

The only other natural tree community in the Main Campus is the coast live oak woodland. Because the oak trees grow on the moister areas of campus, such as in the canyons, they often overlap with the riparian woodland community. A number of wildlife species consume acorns as a seasonal component of their diet (Martin et al. 1961). In much of the coast live oak woodland on the campus, plants of the coastal scrub community also are present in the understory, adding diversity to the woodland community.

The grassland on the campus, like most grassland in California, is dominated by introduced European annual grasses. Additional native and non-native forbs and grasses increase plant species diversity in the grasslands and add to the variety of resources available to wildlife.

The upper elevations of the campus have soils that are mainly rocky and serpentine, and so support a unique yucca scrub flora. The ground cover in this community is dominated by native grasses that can withstand the conditions of the poor soils better than the introduced European grasses. Today, these areas with poor soils are the only places where native grasses are common.

The coastal scrub community provides dense cover, forage and nesting sites for various wildlife species. While under the shrubs, smaller animal species are well concealed from large predators that cannot easily maneuver through the dense vegetation. The variety of plant species within the community provide a wide range of foliage, seeds, etc., to resident wildlife species.

Approximately 75% of the campus is composed of urban, agriculture, and grassland communities; whereas coastal scrub and yucca scrub communities each occupy between 5 and 10 percent of the total area. The coast live oak woodland covers less than 5 percent, although many oak trees grow in the riparian woodland community. The riparian woodland occurs in thin bands along the two creeks and in small patches in a few ravines. The reservoirs cover from 4.3 acres to 900 ft².

A mammalian survey conducted by Cal Poly student Alexandra A. Campbell in 1998 resulted in the identification of 22 mammalian species (Appendix D). Although this survey tried to identify and account for as many species as possible, some expected species still remain undocumented (Appendix E). Table 6 provides a summary of the results in terms of mammalian species richness by habitat type. Coastal scrub supports most detected species, whereas grassland, riparian and chaparral have potential to support a higher number of different species.

Table 6. Mammalian species richness on Main Campus. Number of mammalian species observed is followed by number of species not observed in parentheses.

Mammal Species	Reservoir	Grassland	Buildings/Urban	Riparian	Rock Outcrop	Fence Lines	Yucca Scrub	Coast Live Oak Woodland	Agricultural Field	Coastal Scrub	Chaparral
Marsupials				1 (0)
Insectivores		1 (2)		0 (2)				0 (1)			0 (2)
Lagomorphs		1 (0)								1 (0)	1 (0)
Squirrels		1 (1)						1 (0)		1 (0)	0 (1)
New World Mice		3 (0)	1 (0)	1 (0)				4 (0)		5 (0)	5 (0)
New World Rats								1 (0)		2 (0)	2 (0)
Old World Mice and Rats			1 (0)
Other Rodents		0 (1)	0 (1)	0 (2)				0 (1)		0 (1)	0 (1)
Carnivores		2 (5)	1 (4)	3 (4)				0 (2)		1 (1)	0 (5)
Ungulates		1 (0)	1 (0)	1 (0)				1 (0)		1 (0)
TOTAL SPECIES		9 (9)	4 (5)	6 (8)				7 (4)		11 (2)	8 (9)

The presence of feral cats on the campus are of particular concern because they are the most common mammal species within the campus core (Table 7). There are several areas where many individuals can be found, specifically the areas above the dorms. The cats appear to be extremely territorial and cat fights often were observed during the course of the bird surveys. In addition, presence of the cats may partially account for the lower numbers of mammals observed within the core campus (Campbell 1998).

Table 7. Feral cat colonies sighted within core campus during the mammalian survey conducted in 1998 (Campbell 1998).

Location of Colony	Number of cats
Sierra Madre dorm	15
Yosemite	5
Fremont	5
Science Building	3
Math Building	4
Air Conditioning Building	3
Feed Mill	5
Science North and Fisher Hall	3
University Union	4
Business Building	5

It is estimated that the 40 to 60 million homeless free roaming cats in the U.S. kill more than 100 prey each per year. Extensive studies of the feeding habits of domestic, free-roaming cats show that approximately 20 to 30 percent of the wildlife cats kill are birds (American Bird Conservancy 1997). The Cal Poly Campus Core supports approximately 200 free-roaming cats, representing an estimated loss of 20,000 prey animals each year, of which 4,000 to 6,000 are birds.

An avian species survey conducted by Cal Poly students Bob Wilkerson and Neil Clipperton in 1998 resulted in the identification of 93 avian species present on the Main Campus property (Appendix F). Of the surveyed habitats, the riparian was the most diverse, and the yucca scrub the least (Table 8).

Table 8. Avian diversity in Cal Poly Main Campus. Almost half the species were observed in more than one habitat. The reservoirs were found to be the most exclusive habitat with 14 species not found in any other habitat. The percent of total species indicates the percent of species detected in each of the habitats based on total number of species detected throughout the property.

Although most of the ranch is grasslands, other plant communities also are present (Table 9) providing suitable habitat for a number of wildlife species. The grassland community consists of mostly introduced European annual grasses. The coast live oak woodlands occur both in the higher elevations and in the canyons of the ranch and usually have an understory of non-native grasses. These woodlands range from just a few trees along the creek to nearly closed-canopy woodlands at the higher elevations.

A reptile and amphibian survey was also conducted on Peterson Ranch in 1998 by Cal Poly student Carrie Black. A total of 6 species of reptiles and 4 species of amphibians were visually documented at Peterson Ranch (Appendix J). Species not detected but potentially present on the ranch are listed in Appendix K. The potential exists to support a higher number of different species in the various habitats. While the grassland was the most active habitat in terms of species diversity, the riparian community was the most active in terms of numbers of individual animals observed. Species present at this site were all amphibians with the exception of the Western fence lizard (Sceloporus occidentalis). It is note worthy to mention that the Federally listed Red-legged frog (Rana aurora) was observed in this riparian area.

Table 10. Mammalian species richness on Peterson Ranch. Number of mammalian species observed is followed by number of species not observed in parentheses.

Mammal Species	Reservoir	Grassland	Buildings/Urban	Riparian	Rock Outcrop	Fence Lines	Yucca Scrub	Coast Live Oak Woodland	Agricultural Field	Coastal Scrub	Chaparral
Marsupials			1(0)
Insectivores		0 (1)		0 (3)				0 (1)
Lagomorphs		0 (2)	1(0)		1 (2)						1 (2)
Squirrels			2 (0)	1(0)	1(0)			2 (0)			1 (1)
New World Mice		2 (0)	6 (0)	4 (0)	4 (0)			3 (0)			6 (0)
New World Rats			1(0)	1(0)	1(0)			1(0)			2 (0)
Old World Mice and Rats		0 (1)	1(0)		1(0)			1 (1)
Other Rodents		0 (1)		0 (1)							0 (1)
Carnivores		0 (1)	1 (4)	5 (3)	1 (2)			1 (1)			4 (2)
Ungulates		1(0)	1(0)	2 (0)	1(0)			1(0)			1(0)
TOTAL SPECIES		3 (6)	14 (5)	13 (7)	10 (4)			9 (3)			15 (6)

Table 11. Avian diversity in Peterson Ranch. Almost two-thirds of the species were observed in more than one habitat. The riparian corridor was found to be the most exclusive habitat with 14 species not found in any other habitat. The percent of total species indicates the percent of species detected in each of the habitats based on total number of species detected throughout the property.

Seven plant communities are present within the boundaries of Serrano Ranch, and like most other ranch parcels, grassland covers the greatest area (Table 12). Like other grasslands in the region, introduced annual European grasses account for most of the grassland species.

Plant community	Total Acreage	Percent of total land
Grassland	506	67%
Chaparral-Oak woodland mosaic	92	12%
Riparian	61	8%
Chaparral-Coastal scrub mosaic	40	5%
Ruderal	39	5%
Yucca scrub	15	2%
Coast live oak woodland	1.7	0.2%

A vegetation survey was conducted by Cal Poly student Richard Carroll in 1998. A list of the plants identified in the course of this survey is included in Appendix L.

A mammal survey conducted by Cal Poly student Elizabeth L. Weaver in 1998 confirmed 16 mammal species present in the ranch (Appendix M). A list of species expected but not detected in the course of this survey is included in Appendix N. Table 13 provides a summary of the results in terms of mammalian species richness by habitat type. The riparian corridor supports most detected species, whereas grassland, rock outcrop, coast live oak woodland and coastal scrub have potential to support a higher number of different species.

Table 13. Mammalian species richness on Serrano Ranch. Number of mammalian species observed is followed by number of species not observed in parentheses.

Mammal Species	Reservoir	Grassland	Buildings/ Urban	Riparian	Rock Outcrop	Fence Lines	Yucca Scrub	Coast Live Oak Woodland	Agricultural Field	Coastal Scrub	Chaparral
Marsupials				1 (0)
Insectivores		0 (1)		1 (2)
Lagomorphs		0 (1)		0 (1)						1 (1)
Squirrels		1 (0)		1 (1)	1 (0)			1 (1)		0 (1)
New World Mice		1 (0)		5 (0)	4 (0)			4 (0)		3 (0)
New World Rats				1 (0)	0 (1)
Old World Mice and Rats		0 (1)		0 (1)				0 (1)		0 (1)
Other Rodents		0 (1)
Carnivores		0 (4)		1 (4)	0 (3)			1 (8)		0 (7)
Ungulates		1 (0)								1 (0)
TOTAL SPECIES		3 (8)		10 (9)	5 (4)			6 (10)		5 (10)

Chorro Creek Ranch

Although Chorro Creek Ranch is managed for crops and range, it also supports a diverse assemblage of plant communities. A vegetation survey conducted by Cal Poly student Larry Markle (1998), revealed eight plant communities on Chorro Creek Ranch: agricultural fields, grasslands, coast live oak woodlands, rock outcrops, riparian, ruderal, seeps and streams, and reservoirs (in a broad sense, freshwater marshes. Agricultural fields and grasslands used for grazing are the two largest plant communities in this ranch. Two other communities, less significant in size but most important for wildlife, are coast live oak woodland and riparian corridors (Table 14).

A list of plants identified by Larry Markle (1998) during the course of the vegetation survey on the ranch is included in Appendix O.

Table 14. Acreage of important wildlife habitat at Chorro Creek Ranch. Acreages were calculated using a Bryant transparent grid on Agricultural Map No.3 of 5 of Chorro Creek Ranch and South Walters Ranch (Stechman 1991).

Table 15. Mammalian species richness on Chorro Creek Ranch. Number of mammalian species observed is followed by number of species not observed in parentheses.

Mammal Species	Reservoir	Grassland	Buildings/Urban	Riparian	Rock Outcrop	Fence Lines	Yucca Scrub	Coast Live Oak Woodland	Agricultural Field	Coastal Scrub	Chaparral
Marsupials				1 (0)
Insectivores		1 (0)		1 (1)				0 (1)
Lagomorphs	2 (0)	1 (0)		1 (0)						1 (0)
Squirrels		1 (0)		1 (0)	1 (0)			0 (1)
New World Mice	1 (0)	4 (0)		5 (0)	4 (0)	2 (0)	2 (0)	3 (1)		3 (0)
New World Rats				1 (0)	0 (1)		0 (1)	1 (0)		1 (0)
Old World Mice and Rats	1 (0)	1 (0)			1 (0)			0 (0)
Other Rodents	0 (2)	0 (1)		0 (2)		0 (1)		0 (1)		0 (1)
Carnivores	2 (1)	2 (1)		6 (3)	0 (3)	1 (2)	0 (1)	0 (3)		0 (2)
Ungulates		1 (0)		1 (0)		1 (0)		1 (0)	1 (0)
TOTAL SPECIES	6 (3)	11 (2)		17 (6)	6 (4)	4 (3)	2 (2)	5 (7)	1 (0)	5 (3)

Birds are numerically the most successful terrestrial vertebrates on earth. They occupy and exploit a greater range of habitats than any other class of organism, plant or animal (Welty and Baptista 1988). An avian survey conducted in Chorro Creek Ranch by Cal Poly student Amy Palkovic (1998) detected a total of 93 different species (Appendix R). This survey showed that the riparian areas supported the highest avian diversity (Table 16).

Table 16. Avian diversity in Chorro Creek Ranch. Almost half the species were detected in more than one habitat. The reservoirs were found to be the most exclusive habitat with 20 species not found in any other habitat. The percent of total species indicates the percent of species detected in each of the habitats based on total number of species detected throughout the ranch.

The amount of edge in Escuela Ranch is low due to the high acreage of undivided grassland (EDI = 2.67). A possible way to increase edge would be to split up some of the grasslands with additional communities such as scrub or woodlands.

Table 17. Acreage of the plant communities of Escuela Ranch based upon Bryant Grid calculations. Ruderal communities were too small to calculate acreage from maps and are included within the other communities such as grassland.

The soils in Walters Ranch support high energy grasses and forbs for grazers. Four different plant communitities can be distinguished in the ranch: grasslands, chaparral, riparian and rock outcrop. Grasslands are the dominant community with a variety of grasses and forbs. The only chaparral-oak woodland community in Walters Ranch is located on the top of Walters peak, and comprises less than one acre. A riparian corridor is present along

Table 18. Avian diversity in Escuela Ranch. Almost one third of the species were observed in more than one habitat. The riparian corridor was found to be the most exclusive habitat with 19 species not found in any other habitat. The percent of total species indicates the percent of species detected in each of the habitats based on total number of species detected throughout the ranch. Walters and Chumash Creeks, but this riparian habitat has been altered by past livestock management practices so that most sites lack the presence of large trees, and are more of a wetland than a riparian corridor. Habitat restoration is taking place, and some of the areas are now protected from overgrazing. With proper management and time, this corridor should return to a more natural riparian habitat with Sycamores (Platanus racemosa), Willows (Salix spp.) and Coast live oak (Quercus agrifolia).

Table 19. Mammalian species richness on Walters Ranch. Number of mammalian species observed is followed by number of species not observed in parentheses.

Mammal Species	Reservoir	Grassland	Buildings/ Urban	Riparian	Rock Outcrop	Fence Lines	Yucca Scrub	Coast Live Oak Woodland	Agricultural Field	Coastal Scrub	Chaparral
Marsupials				1 (0)
Insectivores		0 (1)		0 (1)
Lagomorphs		1 (0)		1 (0)		1 (0)
Squirrels		1 (0)		1 (0)	1 (0)
New World Mice		2 (0)		2 (1)	3 (0)	2 (0)
New World Rats
Old World Mice and Rats
Other Rodents		1 (1)		1 (0)	1 (0)
Carnivores		1 (1)		6 (3)	1 (2)
Ungulates		1 (0)		1 (0)
TOTAL SPECIES		7 (3)		13 (5)	6 (2)	3 (0)

Avian surveys were conducted in 1998 by Cal Poly students Nathaniel A. Graveline and Brandy K. Russ. These surveys resulted in the identification of 39 species of birds on the ranch (Appendix W). The grassland and riparian habitats presented the highest species richness (Table 20). Considering the size of the grassland in comparison with the riparian corridor, this provides excellent support for the importance of riparian corridors to avian species.

Table 20. Avian diversity in Walters Ranch. Almost three-quarters of the species were observed in more than one habitat. The grassland was found to be the most exclusive habitat with 5 species not found in any other hahbitat. The percent of total species indicates the percent of species detected in each of the habitats based on total number of species detected throughout the property.

Plant community	Species	Percent of total species
Riparian	31	53%
Grassland	28	48%
Agricultural fields	22	38%
Reservoirs	9	16%

Plant community	Species	Percent of total species
Riparian	38	40.9
Urban	35	37.6
Agricultural fields	33	35.5
Coast live oak woodland	24	25.8
Reservoir	22	23.7
Grassland	19	20.4
Coastal scrub	9	9.7
Yucca scrub	2	2.2

Plant community	Acreage	Percent of total land
Grassland	455.0	70%
Chaparral	65.0	10%
Riparian	65.0	10%
Coast live oak woodland	52.0	8%
Rock outcrops	13.0	2%

Plant community	Species	Percent of total species
Riparian	49	68.1
Coast live oak woodland	37	51.4
Grassland	25	34.7
Chaparral	21	29.2
Ruderal	17	23.6

Plant community	Acreage	Percent of total land
Agricultural fields	280.0	43.7
Grassland	225.0	35.2
Reservoir	79.5	12.4
Riparian	50.0	7.8
Coast live oak woodland	5.5	0.9