Central Valley Floodplain Forest Bird Survey:
2012 Progress Report
Michelle Gilbert, Nathaniel E. Seavy, Tom Gardali, and Catherine Hickey
PRBO Conservation Science
3820 Cypress Drive #11
Petaluma, CA 94954
PRBO Contribution #1925
INTRODUCTION
et al. 2007), indicate the need for continued monitoring
across larger spatial scales in the Central Valley.
California’s Central Valley: Rivers and Birds
Rivers and their floodplains are the basis of highly
productive riparian ecosystems, harboring the most
diverse bird communities in the arid and semiarid
regions of the western United States (Knopf et al. 1988,
Dobkin 1994). Loss of riparian ecosystems may be the
most important cause of population declines among
landbird species in western North America (DeSante
and George 1994), including the decline and extirpation
of many riparian species once common in the Central
Valley (RHJV 2004, CVJV 2006). Riparian areas comprise
less than 0.5% of California’s total land area, yet
support ecosystem integrity and function across
landscapes; they have been identified as the most
important habitat for the protection and conservation
of landbirds in California (Manley and Davidson 1993,
RHJV 2004).
Why Monitor Riparian Birds in the Central Valley?
Birds provide an excellent means to track larger changes
in riparian systems; they occupy a diverse range of
niches, are relatively easy to monitor, and because they
respond to changes in the environment over multiple
spatial scales, birds are ideal study organisms for
monitoring and evaluating ecosystem restoration and
management (Carignan and Villard 2002).
Landbird monitoring has played an important role in
bird conservation planning in California and has
informed riparian restoration guidelines within and
outside of California’s Central Valley. Riparianassociated landbirds are a priority target group
identified by the Riparian Habitat Joint Venture and
California Partners in Flight (RHJV 2004), by the Central
Valley Joint Venture (CVJV 2006) and by the Migratory
Bird Conservation Partnership (camigratorybirds.org).
Status and Trends of Riparian Landbirds in the Central
Valley
In the past 150 years, more than 98% of riparian
vegetation in the Central Valley has been lost or
severely degraded (Smith 1977, Katibah 1984). During
this time, floodplains have been disconnected from the
river and riparian forests have been lost to urban areas
and other land-uses. This loss and alteration of riparian
vegetation has resulted in major changes to the bird
community, with many species experiencing population
declines, range restrictions, or extirpation. Populations
of several California Bird Species of Special Concern are
now rare or declining in the Central Valley (RHJV 2004,
Shuford and Gardali 2008).
While project-level monitoring can provide a
measure of the contribution that a restoration project
makes, regional-scale monitoring is needed to provide
information about Valley-wide progress towards these
regional conservation targets. The Central Valley
Floodplain Forest Bird Survey explicitly addresses a top
priority of the CVJV, as identified in its 2010 Monitoring
and Evaluation Plan, generating data needed to use bird
populations to measure the long-term effectiveness of
investments in riparian ecosystem protection and
restoration.
MONITORING OBJECTIVES
More optimistically, project-scale monitoring of
riparian restoration projects in the Central Valley has
shown that restored floodplain forest is rapidly
colonized by riparian birds, and after as few as 10 years
can provide habitat for a suite of birds similar to those
that occur in mature floodplain forest (Gardali et al.
2006). Additionally, several breeding attempts by at
least one pair of the endangered Least Bell’s Vireo
occurred in 2005-2007 on the San Joaquin River
National Wildlife Refuge in restored riparian (Howell et
al. 2010). At the same time, the failure of some species
(e.g., Lazuli Bunting, Passerina amoena) to respond to
restoration (Gardali et al. 2006), evidence of large-scale
declines in other species (RHJV 2004), and the concerns
that some restored sites may be population sinks (Small
We designed this survey with the following objectives:
Legacy sites
1) Establish long-term monitoring at Central Valley
riparian legacy (historically surveyed) sites to build
upon our knowledge of how birds respond to
riparian restoration.
2) Assess bird use of restoration sites as a measure of
restoration success by (1) comparing abundance
trends on remnant and revegetated sites and (2)
determining annual rate of change in bird
abundance in relation to age of revegetation.
1
System (MGRS) standards (grids courtesy of University
of Florida GeoPlan Center; www.geoplan.ufl.edu). A
100-m resolution grid was most suitable, as it
approximates territory sizes (~1 ha) of some breeding
riparian landbirds, and since linear riparian habitats or
small patches could be missed if larger grids were used
(Roberts et al. 2011). We then identified grid cells
within our 2-km buffer zone which were comprised of at
least 60% riparian vegetation. Our final sampling frame
consisted of roughly 11,500 grid cells (11,500 hectares)
representing locations with enough riparian vegetation
to support breeding riparian landbirds.
Regional sites
3) Within areas of riparian vegetation, estimate
regional densities for as many species of riparian
breeding landbirds as possible.
4) Track regional changes in Central Valley riparian
landbird populations in a manner that accounts for
changes in both bird density and total amount of
available habitat over time.
SAMPLING DESIGN FOR CENTRAL VALLEY RIPARIAN
LEGACY (FIXED-SITE) SURVEYS
PRBO Conservation Science has been conducting
riparian bird surveys in the Central Valley for nearly 20
years. During this time, we have surveyed at more than
800 locations as part of larger efforts to quantify the
bird response to riparian restoration and to compare
bird abundance at remnant and restored riparian areas.
For our fixed locations, we selected 21 legacy sites on 2
National Wildlife Refuge complexes (Sacramento River
NWR complex, and San Luis NWR complex, which
includes the San Joaquin River NWR) for a total 232
point count locations. These sites were selected from
previous long-term studies conducted by PRBO in
Central Valley remnant and restored riparian vegetation
(Table 1) that were recommended sites for continued
landbird monitoring (Gardali et al. 2006, Nur et al. 2006,
Wood et al. 2006).
Selecting Regional Survey Locations
From this sampling frame, we randomly selected
120 regional survey locations using a generalized
random-tessellation stratified (GRTS) sampling design
(Stevens and Olsen 2003, 2004). For our initial year of
sampling, we chose a total of 120 sampling locations,
with 60 sampling locations along each of the
Sacramento and San Joaquin river zones. Selected
locations were a mixture of public and private lands. In
addition, 100 “oversample” locations were created, to
TABLE 1. CVFFBS Legacy sites in California’s
Central Valley.
Site
SAMPLING DESIGN FOR CENTRAL VALLEY REGIONAL
(RANDOM) SURVEYS
Sacramento NWR Complex
Codora
Flynn
Kopta Slough
La Baranca
Ohm
Rio Vista
Phelan Island/Stony Creek
Sul Norte
San Joaquin River NWR
Caswell State Park
Christman Island
Faith Ranch
Hagemann's Field 20
Hagemann’s Peninsula
Hagemann's Field 8 & 9
Hospital Creek
Rose Arambel
San Luis NWR
North San Joaquin
Middle San Joaquin
South San Joaquin
TOTAL
Delineating Our Sampling Frame
We focused on riparian areas of California’s Central
Valley (Fig. 1) within a 2-km buffer along the main stem
of the Sacramento River from Red Bluff to Colusa
(roughly 100 river miles), and along the main stem of
the San Joaquin River from Friant Dam to the
confluence with the Stanislaus River (roughly 200 river
miles). In the agriculture-dominated Central Valley, a 2km buffer on either side of the rivers captures most of
the floodplain of each river and the majority of extant
riparian vegetation.
Within this defined area, we constrained our
sampling frame to areas with sufficient riparian
vegetation to support riparian breeding birds, using
Central Valley Riparian Mapping Project landcover data
(Geographic Information Center 2012). The 2011
medium-scale vegetation layer was overlaid with a 100
x 100-m grid developed from Military Grid Reference
2
Number of points
Remnant Restored
6
11
3
15
13
2
16
8
4
12
15
19
-
16
10
7
11
5
8
7
9
3
-
10
10
12
155
77
current riparian vegetation within our sampling frame
(2-km buffer around mainstems; see Methods section).
use as replacements for any random sites dropped (e.g.,
due to access restrictions or vegetation
misclassifications). All regional point count locations
were separated by at least 200 meters.
Effects of Restoration Age
Some of the legacy sites will be useful for tracking
population or community trends relative to restoration
age or succession, by examining trends in density
estimates over time relative to restoration age. Data
from point count surveys at legacy sites that were prior
to 2002 are omitted, as those older surveys were
conducted using 50-m fixed-radius point count methods
(no distance-to-observer bins), and are not suitable for
distance analyses.
FIELD METHODS
Point Count Protocols
We used point count methods (Ballard et al. 2003,
Ralph et al. 1993) to survey sampling locations twice
during the peak breeding season (once in May and once
in June). Trained surveyors recorded the method of
detection (song, visual, or call), and the estimated
distance to all birds detected in a five minute period.
Survey data were recorded in the field on standardized
data forms. For detailed methods, see
http://data.prbo.org/ cadc2/index.php?page=songbirdpoint-counts.
RESULTS AND DISCUSSION
In 2012, we successfully implemented the first year of
this monitoring effort. Between 1 May and 30 June
2012, we surveyed each of 352 point count locations
(232 legacy points, 120 regional points) twice. We
observed 109 different species at the 120 regional
(randomly chosen) locations. At the legacy sites in
2012, we detected a total of 79 species at survey points
in the Sacramento NWR complex, and within the San
Luis NWR complex, we detected 80 species in the San
Joaquin River NWR and 59 species in the San Luis NWR.
A complete listing of species observed at regional and
legacy sites can be found in Appendices A-D. Of these
species, our analyses in this progress report are on CVJV
focal species.
Data Archiving
All raw datasheets were scanned and digitally stored on
PRBO internal servers. Point count data are stored at
the California Avian Data Center (CADC,
www.prbo.org/cadc), and can be made available to
outside researchers with an account. Point count
vegetation data have been entered into database files,
also stored on PRBO internal servers and available upon
request.
DATA ANALYSIS
Ten special status species were detected during this
year’s survey effort. Bank Swallow (Riparia riparia), a
State Threatened species, was detected at 2 regional
points in the Sacramento Valley. Swainson’s Hawk
(Buteo swainsoni), a State Threatened species, was
detected at one restored and 13 remnant legacy points
in the San Joaquin Valley, and at 2 regional points in the
Sacramento Valley and 16 regional points in the San
Joaquin Valley. Least Bell’s Vireo (Vireo bellii pusillus), a
Federal and State Endangered species, was detected at
1 regional point in the San Joaquin Valley. Black Tern
(Chlidonias niger), and Common Loon (Gavia immer),
both California Bird Species of Special Concern
(hereafter BSSC; Shuford and Gardali 2008), were
detected at one legacy point with remnant vegetation
in the Sacramento Valley. Loggerhead Shrike (Lanius
ludovicianus; BSSC), was detected at one remnant
legacy point in the San Joaquin Valley. Northern Harrier
(Circus cyaneus; BSSC) was detected at one restored
and 2 remnant legacy points in the San Joaquin Valley,
Species Density
For bird species with sufficient detections, we used
distance sampling (Buckland et al. 2001, Thomas et al.
2010), to analyze point count data, fitting detection
function models and obtaining species-specific density
estimates. We analyzed each region (Sacramento
Valley, San Joaquin Valley) separately, and calculated
density estimates using the regional site dataset and
the legacy site dataset separately. Some of the focal
species (Song Sparrow, Yellow Warbler, Common
Yellowthroat) were present in sufficient numbers for
analyses only in the San Joaquin Valley.
Population estimates can be derived by multiplying
these density estimates (birds per hectare) by the area
of current available habitat as mapped by the best
available GIS vegetation layers. To demonstrate, we
used the Central Valley Riparian Mapping Project
landcover data (GIC 2012) to calculate the amount of
3
informing restoration programs and gauging their
success, as well as for improving and updating regional
conservation targets. In 2012, Song Sparrow and
Spotted Towhee density estimates were greater than
CVJV population targets; estimated densities for the
other 3 focal species were below CVJV targets.
and at 5 regional points in the San Joaquin Valley. Song
Sparrow (Melospiza melodia; BSSC), was detected at 73
restored and 17 remnant legacy points in the San
Joaquin Valley, and at 1 regional point in the
Sacramento Valley and 50 regional points in the San
Joaquin Valley. Yellow Warbler (Setophaga petechia;
BSSC), was detected at 3 restored and 2 remnant legacy
points in the Sacramento, at 6 restored and 13 remnant
legacy points in the San Joaquin, and at 3 Sacramento
Valley and 13 San Joaquin Valley regional points. The
Sacramento Valley birds were likely migrants, as they
were only detected in early May. Yellow-breasted Chat
(Icteria virens; BSSC) was detected at 4 restored and
one remnant point in the Sacramento, at 3 remnant
points in the San Joaquin, and at 9 Sacramento Valley
and 2 San Joaquin Valley regional points.
Legacy Sites:
Species density
We estimated densities of 5 CVJV focal species for each
Valley, using the regional sites chosen in 2012 (Table 3).
Two of the focal species (Yellow Warbler, Common
Yellowthroat) in the San Joaquin Valley were present in
very low numbers (< 50 detections) which may affect
precision of the density estimates for these species.
Effects of Restoration Age
Using data from 244 legacy point count sites collected
between 2002 and 2012, and information about what
year a particular site was enhanced or restored, we can
plot trends of species densities as those sites
developed. Two CVJV focal species, Spotted Towhee
and Black-headed Grosbeak, had sufficient sample sizes
for density estimates by restoration age (Figs. 3 and 4).
For both of these species, as restoration age increases,
there is an increasing trend in bird density on the
restored sites.
Regional Sites:
Species density
We estimated densities of CVJV focal species for each
Valley using data from the regional sites (Table 2).
Some focal species were present in sufficient numbers
for analyses only in the San Joaquin Valley.
These density estimates can be compared with CVJV
target population densities for the Sacramento and San
Joaquin valleys (CVJV 2006) and other established
targets, making these data directly applicable to
Table 2. Estimated density (birds/hectare) and confidence limits, for Central Valley Joint Venture focal
species, derived from regional point count locations visited in 2012, and target densities (from CVJV 2006).
Species
Black-headed Grosbeak
Common Yellowthroat
Song Sparrow
Spotted Towhee
Yellow Warbler
2012 Density (95% confidence interval)
Sacramento Valley
San Joaquin Valley
1.111 (0.921, 1.341) 0.313 (0.211, 0.4627)
-0.311 (0.197, 0.492)
-2.36 (1.8, 3.096)
2.499 (2.158, 2.893)
3.06 (2.529, 3.702)
-0.192 (0.099, 0.373)
CVJV Target Density
Sacramento San Joaquin
1.334
0.371
0.247
0.494
0.988
1.680
1.927
1.927
0.321
0.321
Table 3. Estimated density (birds/hectare) and confidence limits, for Central Valley Joint
Venture focal species, derived from legacy point count locations visited in 2012.
Species
Black-headed Grosbeak
Common Yellowthroat*
Song Sparrow
Spotted Towhee
Yellow Warbler*
2012 Density (95% confidence interval)
Sacramento Valley
San Joaquin Valley
0.807 (0.658, 0.989)
0.181 (0.119, 0.278)
-0.077 (0.040, 0.151)
-3.287 (2.198, 4.916)
2.235 (1.923, 2.597)
2.788 (2.411, 3.224)
-0.264 (0.139, 0.501)
*estimates created using fewer than 50 detections
4
Figure 3: Estimated Spotted Towhee density (birds/ha) at
restored legacy sites, relative to restoration age.
adaptively manage the region and ensure the long-term
persistence of birds and other riparian-dependent
wildlife. Incorporating landbird monitoring into nonavian focused riparian restoration projects can
transform a single-species focused restoration project
into a multi-species community-based effort that will
maximize wildlife benefits. Additionally, if future
changes to river flows and/or habitat restoration
activities occur, continued avian monitoring will be
desirable to quantify the effects to birds, and to provide
the documentation and accountability for those
providing funding for conservation actions.
Potential shifts in the distribution of riparian
habitats may be increasingly relevant in light of rapid
environmental change. Thus, tracking available habitat
in the Central Valley over time is needed to maximize
the accuracy of the population estimates from point
count data. If mapping efforts similar to the recent
Central Valley Riparian Mapping Project continue to be
updated and available, we can adjust our sampling
frame with the latest information, and can combine
these vegetation assessments with our species density
estimates to more accurately calculate bird population
changes.
Figure 4: Estimated Black-headed Grosbeak density (birds/ha)
at restored legacy sites, relative to restoration age.
ACKNOWLEDGEMENTS
We are especially grateful for the participation and
support of several private landowners of the
Sacramento Valley and San Joaquin Valley who allowed
us to survey their properties. For valuable logistical
assistance and survey permissions, we thank the staff of
the Sacramento NWR complex, San Luis NWR complex,
CA Department of Fish & Wildlife, CA Parks and
Recreation, CA Department of Water Resources, US Fish
and Wildlife Service, San Joaquin River Conservancy,
San Joaquin River Parkway & Conservation Trust, River
Partners, The Nature Conservancy, and Audubon
California. Thanks to Cory Gregory, Kristin Sesser, Simon
Avery, and Justin Bosler for their hard work in the field,
and to Mark Dettling for coordination of Sacramento
Valley survey efforts. Matthew Reiter and L. Jay Roberts
provided helpful comments on survey design. Our work
was funded, through the Migratory Bird Conservation
Partnership, by the S.D. Bechtel, Jr. Foundation. This is
PRBO Contribution number 1925.
Future Directions
We will conduct a second year of surveys in summer
2013, revisiting the legacy sites, and re-randomizing our
regional survey locations. Our regional survey locations
are not intended as permanent sampling locations; new
sites are re-selected using GRTS methods from the
riparian sampling grid each year.
By assessing changes in riparian landbird
populations throughout the Central Valley, we can
provide stakeholders with information vital to
5
Knopf, F. L., R. R. Johnson, T. Rich, F. B. Samson, and R.
C. Szaro. 1988. Conservation of riparian ecosystems in
the United States. Wilson Bulletin 100:272-284.
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Geupel. 2006. Trends in Avian Abundance and Diversity
in Restored and Remnant Riparian Habitat on the
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California Bay-Delta Authority Ecosystem Restoration
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Jongsomjit, and D. Stralberg. 2008. The California Avian
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DeSante. 1993. Handbook of field methods for
monitoring landbirds. USDA Forest Service Publication,
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Geupel. 2011. Sierra Nevada National Forests
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Ecology 14(3): 391-403.
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Figure 1: Focal sampling area, highlighted in dark blue, along the main stems of the Sacramento River (left panel) and
San Joaquin River (right panel).
7
Appendix A: List of bird species detected at the randomly-selected regional survey locations in 2012.
Common Name
Acorn Woodpecker
American Bittern
American Coot
American Crow
American Goldfinch
American Kestrel
American Robin
American White Pelican
Anna's Hummingbird
Ash-throated Flycatcher
Audubon's Warbler
Bank Swallow
Barn Owl
Barn Swallow
Bell's Vireo (Least Bell’s Vireo)
Belted Kingfisher
Bewick's Wren
Black Phoebe
Black-chinned Hummingbird
Black-crowned Night-Heron
Black-headed Grosbeak
Black-necked Stilt
Blue Grosbeak
Brewer's Blackbird
Brown-headed Cowbird
Bullock's Oriole
Bushtit
California Quail
California Thrasher
California Towhee
Canada Goose
Cassin's Vireo
Cattle Egret
Cedar Waxwing
Cliff Swallow
Common Peafowl
Common Raven
Common Yellowthroat
Double-crested Cormorant
Downy Woodpecker
Eurasian Collared-Dove
European Starling
Forster's Tern
Gadwall
Golden-crowned Sparrow
Great Blue Heron
Great Egret
Great Horned Owl
Great-tailed Grackle
Green Heron
Hermit Thrush
House Finch
House Sparrow
House Wren
Hutton's Vireo
Killdeer
Lark Sparrow
Lazuli Bunting
Lesser Goldfinch
Loggerhead Shrike
Mallard
Marsh Wren
Mourning Dove
Northern Flicker
Northern Harrier
Northern Mockingbird
Northern Pintail
Northern Rough-winged Swallow
Nuttall's Woodpecker
Oak Titmouse
Orange-crowned Warbler
Osprey
Pacific-slope Flycatcher
8
Phainopepla
Pied-billed Grebe
Red-shouldered Hawk
Red-tailed Hawk
Red-winged Blackbird
Ring-necked Pheasant
Sharp-shinned Hawk
Snowy Egret
Song Sparrow
Spotted Sandpiper
Spotted Towhee
Swainson's Hawk
Swainson's Thrush
Tree Swallow
Tricolored Blackbird
Turkey Vulture
Warbling Vireo
Western Bluebird
Western Kingbird
Western Meadowlark
Western Scrub-Jay
Western Tanager
Western Wood-Pewee
White-breasted Nuthatch
White-faced Ibis
Wild Turkey
Willet
Willow Flycatcher
Wilson's Warbler
Wood Duck
Wrentit
Yellow Warbler
Yellow-billed Magpie
Yellow-breasted Chat
Yellow-headed Blackbird
Yellow-rumped Warbler
Appendix B: Bird species detected at survey locations on the Sacramento National Wildlife Refuge Complex in 2012.
Common Name
Acorn Woodpecker
American Crow
American Goldfinch
American Robin
American White Pelican
Anna's Hummingbird
Ash-throated Flycatcher
Barn Swallow
Belted Kingfisher
Bewick's Wren
Black Phoebe
Black Tern
Black-chinned Hummingbird
Black-headed Grosbeak
Brewer's Blackbird
Brown-headed Cowbird
Bullock's Oriole
Bushtit
California Quail
California Towhee
Canada Goose
Cedar Waxwing
Cliff Swallow
Common Loon
Common Peafowl
Common Raven
Common Yellowthroat
Cooper's Hawk
Double-crested Cormorant
Downy Woodpecker
Eurasian Collared-Dove
European Starling
Golden-crowned Sparrow
Great Blue Heron
Great Horned Owl
Hermit Warbler
House Finch
House Wren
Hutton's Vireo
Killdeer
Lark Sparrow
Lazuli Bunting
Lesser Goldfinch
Mallard
Mourning Dove
Northern Flicker
Northern Mockingbird
Northern Rough-winged Swallow
Nuttall's Woodpecker
Oak Titmouse
Orange-crowned Warbler
Osprey
Pacific-slope Flycatcher
9
Phainopepla
Pied-billed Grebe
Red-shouldered Hawk
Red-tailed Hawk
Red-winged Blackbird
Spotted Towhee
Swainson's Hawk
Swainson's Thrush
Townsend's Warbler
Tree Swallow
Tricolored Blackbird
Turkey Vulture
Warbling Vireo
Western Bluebird
Western Kingbird
Western Scrub-Jay
Western Tanager
Western Wood-Pewee
White-breasted Nuthatch
Wild Turkey
Wilson's Warbler
Wood Duck
Wrentit
Yellow Warbler
Yellow-billed Magpie
Yellow-breasted Chat
Appendix C: Bird species detected at survey locations on the San Joaquin River National Wildlife Refuge in 2012.
Common Name
Acorn Woodpecker
American Coot
American Crow
American Goldfinch
American Kestrel
American Robin
Anna's Hummingbird
Ash-throated Flycatcher
Audubon's Warbler
Barn Owl
Barn Swallow
Belted Kingfisher
Bewick's Wren
Black Phoebe
Black-chinned Hummingbird
Black-crowned Night-Heron
Black-headed Grosbeak
Black-necked Stilt
Blue Grosbeak
Brewer's Blackbird
Brown-headed Cowbird
Bullock's Oriole
Bushtit
California Quail
California Thrasher
California Towhee
Canada Goose
Cedar Waxwing
Cliff Swallow
Common Raven
Common Yellowthroat
Cooper's Hawk
Double-crested Cormorant
Downy Woodpecker
Eurasian Collared-Dove
European Starling
Gadwall
Golden-crowned Sparrow
Great Blue Heron
Great Egret
Great Horned Owl
Great-tailed Grackle
House Finch
House Wren
Killdeer
Lazuli Bunting
Lesser Goldfinch
Loggerhead Shrike
Mallard
Marsh Wren
Mourning Dove
Northern Flicker
Northern Harrier
10
Northern Mockingbird
Northern Rough-winged Swallow
Nuttall's Woodpecker
Oak Titmouse
Pied-billed Grebe
Red-tailed Hawk
Red-winged Blackbird
Ring-necked Pheasant
Snowy Egret
Song Sparrow
Spotted Towhee
Swainson's Hawk
Townsend's Warbler
Tree Swallow
Warbling Vireo
Western Bluebird
Western Kingbird
Western Scrub-Jay
Western Wood-Pewee
White-breasted Nuthatch
White-faced Ibis
Wild Turkey
Wilson's Warbler
Wood Duck
Wrentit
Yellow Warbler
Yellow-billed Magpie
Appendix D: Bird species detected at survey locations on the San Luis National Wildlife Refuge in 2012
Common Name
American Bittern
American Crow
American Goldfinch
American Robin
Ash-throated Flycatcher
Barn Swallow
Bewick's Wren
Black Phoebe
Black-crowned Night-Heron
Black-headed Grosbeak
Blue Grosbeak
Brewer's Blackbird
Brown-headed Cowbird
Bullock's Oriole
Bushtit
California Quail
California Towhee
Cliff Swallow
Common Yellowthroat
Cooper's Hawk
Double-crested Cormorant
Downy Woodpecker
European Starling
Great Blue Heron
Great Egret
Great Horned Owl
Green Heron
House Finch
House Sparrow
House Wren
Killdeer
Lark Sparrow
Lazuli Bunting
Mallard
Marsh Wren
Mourning Dove
Northern Flicker
Northern Harrier
Northern Mockingbird
11
Northern Rough-winged Swallow
Nuttall's Woodpecker
Pied-billed Grebe
Red-tailed Hawk
Red-winged Blackbird
Ring-necked Pheasant
Snowy Egret
Song Sparrow
Spotted Towhee
Swainson's Hawk
Tree Swallow
Western Kingbird
Western Meadowlark
Western Scrub-Jay
Western Tanager
Western Wood-Pewee
Wilson's Warbler
Wood Duck
Yellow Warbler
Yellow-breasted Chat