California Partners in Flight—Bird Conservation Plan
Oak Titmouse
     Baeolophus inornatus, synonym: Parus inornatus
 

PREPARED BY:

M. Flannery, Point Reyes Bird Observatory, 4990 Shoreline Hwy., Stinson Beach, CA 94970.
Phone: (415) 868-0655.  Email: mflannery at prbo dot org SPECIES: Oak Titmouse (Baeolophus inornatus, synonym: Parus inornatus) In 1996 because of differences in voice, morphology, coloration, ecology, and genetics Baeolophus inornatus was split into two species: Baeolophus inornatus, Oak Titmouse, and Baeolophus griseus, Juniper Titmouse (Auk 1997, AOU 1998) SUBSPECIES STATUS: Baeolophus inornatus restrictus, B. i. inornatus,

B. i. sequestratus, B. i. griseus, B. i. murinus, B. i. affabilis, B. i. transpositus,

B. i. mohavensis, B. i. cinceraceus

MANAGEMENT STATUS:

range map:

 

  1. Historical references: The following historical references were all obtained from Grinnell and Miller, 1944.
Baeolophus inornatus inornatus: Klamath, Sacramento Valley, Central Coast, San Joaquin Bioregions: Found in western California below 3000ft, from Mendocino County and head of Sacramento Valley south to Santa Barbara and Tulare counties. Populations were located in the northwest coast region, Cahto and Covelo, Mendocino County; northernmost around the head of the Sacramento Valley, Tower House and Baird Station, Shasta County. Sierra Bioregion: Easternmost found at Nevada city, Nevada County; Yosemite Valley, Mariposa County; Three Rivers, Tulare County. Integrades southward with P. i. Kernsensis in the westward foothills of the Sierra Nevada in Fresno and Tulare counties. Central Coast Bioregion:
        Located in the coast belt in Santa Barbara and Ventura counties. B. i. sequestratus: Klamath Bioregion: Recorded presence in Shasta Valley, Siskiyou County, and the valley of South Fork of the Trinity river, western Trinity County; three definite localities: near Bogus at 2500 ft, Siskiyou County; at the Caves, 11 miles northeast of Weed; and at 1 mile west of Hyampom, Trinity County. B. i. transpositus: Central Coast Bioregion: Oak Titmouse is found west of the desert divides in southern California, southeast from Santa Barbara and Ventura counties. Southcoast Bioregion: The extreme eastward point of sighting are Palmdale, in northern Los Angeles County; Also found at Campo, San Diego County.         Mojave Bioregion:
                    Populations in Hesperia, San Bernadino County; Cactus Flat and Quail Spring, north and east of the San Bernadino mountains.

        Colorado Desert Bioregion:
                    Found at the Santa Rosa mountains at 6000 ft, Riverside County.
 
 

II. Current breeding distribution:

A.  Expert opinion:

    Bay/Delta Bioregion:
            Sacramento County: Identified as a breeder at Cosumnes River Preserve. (Lynes pers.comm1999)
     
     
B.  Point count (singing individual encountered on 2 or more different days of census-at least one week apart):
    Klamath Bioregion:
            Recorded on the Upper Sacramento River in 1996. (PRBO data)

            Breeder in the Mendocino National Forest 1996 and 1997. (PRBO data)

    Sacramento Valley Bioregion:
            Detected during the breeding seasons 1997 and 1998 at the East Park Reservoir. (PRBO data)

            In 1997 and 1998 recorded as a known breeder at the Lower Sacramento River Project. (PRBO data)

    Sierra Bioregion:
            Counted at the Tejon Ranch, Kern County and the California and Blodgett Forest Research Station, El Dorado County. (Block and Morrison 1987)

    Bay Delta Bioregion:
            Recorded during point counts 1995-1998 at Cosumnes River Preserve. (PRBO data)

C.  Mist netting (female with brood patch, female with eggs in oviduct, juvenile with no skull ossification before 1 August):
    Sacramento Valley Bioregion:
            Captured 34 Oak Titmice during the breeding seasons 1997 and 1998 at the East Park Reservoir. 1997 - 6 females with brood patches, 26 hatch year birds; 1998 – 1 female with brood patch (PRBO data)

            During 1996 – 1998 field season Oak Titmice were banded at the Lower Sacramento River Preserve. Number of females caught with brood patches were: 3 in 1996, 2 in 1997, and 1 in 1998. (PRBO data)

    Bay Delta Bioregion:
            Recorded 8 females with brood patches in 1995, and 3 in 1998 at Cosumnes River Preserve. (PRBO data)
     
     

D.  Nest searching:
    Klamath Bioregion:
            Nests were located in 1986 and 1987 at the University of California Hopland Field Station in Mendocino County for a study on covariance patterns among birds and vegetation. (Wilson, et al 1991)

    Sacramento Valley Bioregion:
            East Park Reservoir: 3 nests found in 1997, 1 in1998. (PRBO data)

            Lower Sacramento River Project produced 8 nests in 1995 and 1 in 1998. (PRBO data)

    Bay Delta Bioregion:
            In 1996-1998 a mean number of 5 nests were found at the Cosumnes River Preserve. (PRBO data)

    Central Coast Bioregion:
            San Luis Obispo Co.: Breeding at Camp Roberts Military Base (Tietje and Vreeland 1997)

    San Joaquin Bioregion:
            Studied in nest boxes and cavities between 1989 and 1991 on the San Joaquin Experimental Range (Purcell 1995)
     

 E.  Spot mapping:
    San Joaquin:
        Madera Co.: Territories were mapped on San Joaquin Experimental Range. (Verner, et.al. 1997)
     
F.  Area search:
    Klamath Bioregion:
        Area censuses conducted 1986 and 1987 at the University of California Hopland Field Station in Mendocino County. (Wilson, et al 1991)

        Between 1989 and 1990 Oak Titmice were abundant during searches both east and northeast of Shasta Valley, approximately 15-25 individuals per morning. (Cicero 1996)

    Modoc Bioregion:
        Between 1990 – 1992 population densities west of Clear Lake through the Modoc Plateau ranged from 1-3 pair per day at Doris and Red Rock Valley and 4-7 pair per day west-northwest of Lava Beds National Monument. (Cicero 1996)

    Sierra Bioregion:
        3-4 pair per day found at Walker Pass, Kern County during studies conducted 1989-1991. (Cicero 1996)

    Mojave Bioregion:
        Only a few birds were sighted at White-Inyo Mountains, Inyo County, Black Rock Canyon, Joshua Tree Monument during 4 visits 1989-1991. (Cicero 1996)

G.  Breeding Bird Atlas:
    The distribution of the Oak Titmouse is complex and discontinuous in California. They are absent from the extreme northwest coastal region, and portions of extreme north-central California, from the Cascades-Sierra axis. This species is also not found in the San Joaquin valley, lowlands of eastern and south eastern deserts, as well as a few coastal areas in southern California. Otherwise found in suitable habitat throughout the state. (Small 1994)

    Breeds in interior of eastern Marin County, including the hills around Novato. Rare and local on the Point Reyes Peninsula.

    (Shuford 1993)

    In the South Bay area the Oak Titmouse is found in the canyon bottoms of the Diablo range and over most of the lower portions of the Santa Cruz mountains. (Sibley 1952)
     
     

H.  BBS route:
            Detected on 96 BBS routes throughout California during the time period 1980-1996. (Data from that time period includes both Oak Titmouse and Juniper Titmouse.)   More specifically, the Oak Titmouse was recorded on 50 routes in the California Foothills 1980-1996.(Sauer 1997)

I.  Other/Local opinion:
            Bay/Delta Bioregion:
                    Found in 1998 at Bear Valley visitor center, Point Reyes National Seashore during unofficial search. (Humple pers. comm 1999)

     
ECOLOGY:

I.  Average territory size:
Mean territory size of 6.3 acres with a range of 3.3-12.5 acres in Alameda County. (Dixon 1949) In San Mateo County mean territory size was 2.0 acres. (Hertz et al, 1976)

II. Time of occurrence and seasonal movements.

A. Arrival date on breeding grounds: sedentary, year-round resident

B. Departure date from breeding grounds: N/A, year-round resident

C. Spring migration period: Year-round resident

           D. Fall migration period: Year-round resident

          E.  Extent of wintering in CA: Year-round resident, defends territory throughout the year. (Verner and Boss 1980)

          F.  Migration stop-over needs/characteristics:

          G.  Stop-over period: N/A

          H.  Habitat use: N/A

          I.  Routes: N/A
 

III. Nest type: Secondary cavity nest using natural cavities, woodpecker holes and/or nest boxes (Dixon 1949)

Materials used to form a nest within the cavity are grass, hair, moss, feathers, shredded bark, cotton and/or wool, straw, plant down or blossoms, twigs, twine or string, plant fibers, rootlets, snakeskin, wood chips, and leaves. The nest lining is made up primarily of soft material such as hair and/or feathers. (Cicero 1996)
 
  IV. Foraging strategy:
        The Oak Titmouse requires an elevated niche, where it forages foliage, twigs, branches, and trunks. It is occasionally seen foraging on the ground. It’s foraging methods include gleaning, hammering hard seeds, chipping bark, and sometimes hovering. (Block 1990)
        At the San Joaquin Experimental Range Oak Titmice foraged more often on blue oak (Quercus douglasii) primarily on the foliage in April and on the reproductive parts in May. During March they foraged in live oak (Q. wislizenii) and in May they used gray pine (Pinus sabiana). Within season foraging changes were due to plant phenology. (Hejl and Verner 1990)
 
 

V. Social Organization:

    A.  Typical breeding densities:

    On San Joaquin Experimental Range on two 29.7-ha plots there was a mean number of 14.1 territories on the ungrazed plot and 19.6 territories on the grazed plot. (Verner et. al 1997) At Camp Roberts Military base in San Luis Obispo County there were recorded 46.1 territories per 100 acres. (Tietje and Vreeland 1997)
    B.  Mating system: Monogamous with adults permanently paired. Pair formation occurs in young birds in early fall soon after the family unit breaks up. (Dixon 1949)
    C.  Delayed breeding (where are immature birds?): no information.
    D. Post fledging biology of offspring: Oak Titmice remain in a family group after the young have fledged, often moving away from the nest to an area of the territory infrequently used. (Dixon 1949)
    E.  Post breeding social behavior (mixed species flocks, or simply migrate away?): They occasionally form mixed-species flocks during the nonbreeding season. (Ehrlich et al 1988, Ziener 1990)

VI. Clutch size: Variable clutch size with a mean of 6.75. (Dixon 1949) At San Joaquin Experimental Range the mean clutch size was 5.81. (Purcell 1995) Range of 3-9 eggs, usually 6-8. (Ziener 1990)

VII.. Incubating sex: Female. (Dixon 1949)

VIII.. Incubation period: 14-16 days. (Dixon 1949)

VIX.. Nestling period: approximately three weeks. (Dixon 1949) The San Joaquin Experimental range reported a mean 41 day nestling period.(Purcell 1995)

X. Development at hatching: Altricial (Ehrlich et. al. 1988)

XI. Number of broods: Single brood. (Dixon 1949)

XII. Who tends the young: Both parents tend Young. (Dixon 1949)

XIII. Diet:

    A.  Major food items (by season):
            No season-specific information. In general 43% animal and 57% vegetable. (Dixon 1949) The animal food is made up of true bugs, caterpillars, beetles, wasps, ants, spiders, and other insects. Vegetable food contains cultivated fruits and grains, wild fruits, seeds and nuts, leaf galls, oak and willow catkins, and leaf buds. (Dixon 1949)

    B.  Drinking: Considered an occasional drinker (drank on half or fewer of the days with a maximum temperature of 25° C or above) based on Fisher water- dependence categories in Williams and Koenig, 1980.

XIV. Wintering ground needs and distribution: Same as on the breeding grounds.
 
 

BREEDING HABITAT AND NEST SITE CHARACTERISTICS:

I. Overview of breeding habitat:, Oak Titmice prefer a woodland habitat in which oaks predominate. (Grinnell and Miller, 1944) In Marin County Oak Titmice occupy woodlands, oak savannah, open broad-leaved evergreen forests, and riparian woodlands. The open broad-leaved evergreen forest must be spacious, have oaks, and be on south-facing slopes. (Shuford 1993) Oak and pine-oak woodland, arborescent chaparral, oak-riparian associations. (AOU 1998)

II. Nest Site.

    A.  Substrate (species): The Oak Titmouse uses a variety of tree species. At San Joaquin Experimental Range 60% of the excavated cavities were in blue oak (Quercus douglasii), 35% in live oak (Q. wislizenii), and 5% in snags. Of the natural cavities used as nest sites 47% were in blue oak, 48% in live oak and 3% in snags. (Purcell and Verner 1995)

    B.  Height of nest: Ranges from 3 – 32 ft. (Verner and Boss 1980)

III. Vegetation surrounding the nest (Importance of each category may differ by species)

    A.  Canopy cover: At Camp Roberts Military Base 40-70% canopy cover. A dense tree canopy is important for this foliage gleaner. (Tietje and Vreeland 1997)
    B.  Dominant plant species in canopy: Blue Oak (Quercus douglasii). (Tietje and Vreeland 1997)
    C.  Average shrub cover: 27% shrub cover at Camp Roberts. (Tietje and Vreeland 1997)
    D.  Dominant shrub species: N/A
    E.  Average forb cover: N/A
    F.  Dominant forb species: N/A
    G.  Ground cover: 20% downed woodcover, 28% unvegetated groundcover. (Tietje and Vreeland 1997)
    H.  Slope: no information
    I.  Aspect: no information
    J.  Tree DBH: In Hopland, CA the average tree DBH was 31cm (Wilson 1991)
    K.  Snags: Snags with natural or excavated holes were used only 8% of the time at the San Joaquin Experimental Range. (Purcell and Verner 1995)
    L.  Distance to water: Often breeds near water. (Ziener)

IV. Landscape factors

    A.  Elevation: Seldom ranges above 3500ft. (Bent 1964)
    B.  Fragmentation: no information
    C.  Patch size: no information
    D.  Disturbance (natural or managed): (e.g. floods, fires, logging) no information
    E.  Adjacent land use: no information
 V. Other:

SPECIAL FACTORS: Factors influencing a species occurrence and viability.

I.  Brood parasitism: no information

II.  Dietary: no information

III.  Sensitivity to human-induced disturbance: no information

IV.  Pesticide use: no information

V.  Predators: Suffers depredation from the usual predators of passerines, namely small mammals and hawks. (Ziener 1990) Western Scrub Jay may depredate eggs and nestlings. (Bent 1946)

VI.  Exotic species invasion/encroachment: The proliferation of the European Starling, may pose an indirect threat to the Oak Titmouse. (Purcell 1995)

VII. Other: The Protocalliphorid blowfly larvae are parasites of secondary cavity nesters as they lay their eggs in the additional material used to line the nest cavity. A high rate of parasitism was recorded in nests at San Joaquin Experimental Range. (Purcell and Verner 1995)
 

POPULATION TREND: http://www.mbr.nbs.gov/bbs/bbs.html

Data censusing both the Oak and Juniper Titmice showed a 1.9% decline per year throughout California (p<.05) 1980-1996 and a 1.6% annual decline in the California foothills population of Oak Titmice during 1966-1996 (p=.06). (Sauer, 1996)
 

DEMOGRAPHICS:

I.  Age and sex ratios: no information.
II.  Productivity measure(s): The San Joaquin Experimental Range study of cavity nesters reported a Mayfield estimate of nesting success of 62% in natural cavities and 60% in nest boxes. (Purcell 1995)
III.  Survivorship: Two-thirds of the birds fledged did not survive until the next breeding season. (Dixon 1949)
IV.  Dispersal:
        According to Dixon (1949) dispersal is gradual and restricted, 4 of the 7 birds recorded established territories in their natal area the following season. The median distance of dispersal was approximately 600 meters. (Dixon 1949)
 

MANAGEMENT ISSUES:

ASSOCIATED SPECIES: A list of other species that would benefit from management of the target species. Other species that would benefit from management of the Oak Titmouse are other oak woodland cavity nesters, including: Acorn Woodpecker
Ash-throated Flycatcher
Bewick's Wren
Downy Woodpecker
House Wren
Nutall's woodpecker
Red-shafted Flicker
Violet-green Swallow
White-breasted Nuthatch
 
  MONITORING METHODS AND RESEARCH NEEDS: Recommend methods that will address immediate needs as well as those most appropriate to monitor how effective the proposed management recommendations will be.

More information about the breeding requirements of the Oak Titmouse is essential in forming management recommendations. The literature concerning this species is primarily related to genetic variation and does not adequately address breeding biology. More direct studies of breeding biology and habitat requirements are suggested. Nest monitoring is one method that would be helpful in assessing the status and needs of this species.
 
 

Section 2: Action plan summary.

STATUS (from subspecies, trend, local extirpations, state and federal lists, etc.)
    Experiencing a 1.9% decline per year throughout California (p<.05) 1980-1996 and a 1.6% annual decline in the California foothills 1966-1996 (p=.06). (Sauer, 1996)

HABITAT NEEDS (e.g., elevation, patch size, breeding habitat characteristics, disturbance)
    Requires oak and pine-oak woodlands with adequate natural or excavated cavities for nesting and sufficient canopy cover for foraging and roosting.

CONCERNS (e.g., productivity, brood parasitism, habitat loss, lack of information, wintering distribution, pesticide use)
    Habitat is one major concern in the conservation of the Oak Titmouse. The loss of dead standing trees, live trees with dead limbs or diseased trees reduces the number of cavities available for nesting.
    The significant decline since 1980 of this species requires further study to determine future conservation goals.

OBJECTIVES (e.g., increase distribution, identify healthy breeding populations, increase available habitat, guide restoration efforts to benefit species)
    The objective is to prevent further decline in this species and to increase suitable habitat.

ACTION (e.g., acquire and restore habitat, specific management and restoration recommendations, specific research and monitoring needs, specific land protection recommendations)
    The reduction of habitat loss can be achieved by increasing the number of dead standing oak species, especially important are live trees with dead limbs and diseased trees in which the heartwood decays. These trees should remain standing for use by cavity-nesting birds. A canopy cover of 40-70% should be the objective when thinning oak woodlands.
    Further research and monitoring is needed to gather more information specifically on the Oak Titmouse requirements.
 

SCIENTIFIC REFERENCES:

American Ornithologists’ Union. 1983. Check-list of North American Birds. 7th edition. American Ornithologists’ Union, Washington, D.C.

AOU checklist. 1997. Supplement Auk 114: 542-552.

Aigner, P. A., W.M. Block, and M.L. Morrison. 1998. Effect of firewood harvesting on birds in a California oak-pine woodland. J. Wildl. Manage. 62(2):485-497.

Balda R. P. 1975. The relationship of secondary cavity nesters' snag densities in western coniferous forests. USDA Forest Service Wildlife Habitat Technical Bulletin 1, 37p. Southwestern Region, Albuquerque, NM.

Bent, A. C. 1064. Life histories of North American Jays, Crows, and Titmice. Dover Publications, Inc., New York, NY.

Block, W. M. and M. L. Morrison. 1986. Conceptual framework and ecological considerations for the study of birds in oak woodlands. In Proc., Symposium on multi-use management of California's hardwood resources [San Luis Obispo, CA, Nov. 12-14, 1986] USDA For. Serv. Gen. Tech. Rep., PSW-100, p. 163-173.

Block, W.M. 1990. Geographic variation in foraging ecologies of breeding and nonbreeding birds in oak woodlands. Studies in Avian Biology 13: 264-269.

Cicero, C. 1996. Sibling species of titmice in the Parus inornatus complex. University of California Publications in Zoology 128: 1-217.

DeBenedictis, P. 1997. Complex titmice. Birding 29: 238-241.

DeBenedictis, P. 1993. A desert barrier. Birding 25: 437-438.

Dixon, K. L. 1954. Some ecological relations of chickadees and titmice in central California. Condor 56: 113-124.

Dixon, K. L. 1949. Behavior of the Plain Titmouse. Condor 51:110-136.

Ehrlich, P.R., Dobkin, D.S, and D. Wheye. 1988. The birder's handbook: a field guide to the natural history of North American birds. Simon and Schuster Press, NY.

Gardali, T, G.R. Geupel, and G. Ballard. 1996. Songbird census in Brewer's oak forest in the Mendocino National Forest: Results from the 1996 field season. Unpublished report of the Point Reyes Bird Observatory to the Mendocino National Forest Service.

Geupel, G., G. Ballard, and A. King. 1997. Songbird monitoring on the Cosumnes River Preserve: results of the 1995 field season. Unpublished report. Point Reyes Bird Observatory, Stinson Beach, CA.

Geupel, G., G. Ballard, N. Nur, and A. King. 1997. Population status and associations of songbirds along riparian corridors of the Lower Sacramento River: results from 1995 field season and summary of results 1993-1995. Unpublished report. Point Reyes Bird Observatory, Stinson Beach, CA.

Geupel, G., and G. Ballard 1995. Status and distribution of the landbird avifauna along riparian corridors of the Sacramento River National Wildlife Refuge: results of the 1994 field season. Unpublished report. Point Reyes Bird Observatory, Stinson Beach, CA.

Geupel, G., N. Nur, G. Ballard, and A. Kiener. 1996. Monitoring nests of songbirds and their associated vegetation in montane meadows of the San Bernardino National forest, results of the 1992-1995 field seasons. Unpublished report to the USFS. Point Reyes Bird Observatory, Stinson Beach, CA.

Grinnell, J. and A.H. Miller. 1944. The distribution of the birds of California. Artemesia Press, Lee Vining, CA.

Hejl, S. J., J. Verner. 1990. Within-season and yearly variations in avian foraging locations. Studies in Avian Biology 13:202-209.

Hertz, P. E., J. V. Remsen, Jr., and S. I. Zones. 1976. Ecological complementarity of three sympatric parids in a California oak woodland. Condor 78: 307-316.

Johnson, L. S. 1987. Pattern of song type use for territorial defense in the plain titmouse Parus inornatus. Ornis. Scandinavica 18: 24-32.

King, A and G. Geupel. 1997. Songbird response to revegetation along the Sacramento River: results from 1996 field season. Unpublished report. Point Reyes Bird Observatory, Stinson Beach, CA.

Kleintjes, P. K. and D. L. Dahlsten. 1992. A comparison of three techniques for analyzing the arthropod diet of plain titmouse and chestnut-backed chickadee. Journal of Field Ornithology 63(3): 276-285.

Martin, T. E. and P. Li. 1992. Life history traits of open-vs. cavity-nesting birds. Ecology 73(2):579-592.

McClelland, B.R., S.S. Friswell, W.C. Fischer, and C.H. Halvorson. 1979. Habitat management for hole-nesting birds in forests of western larch and Douglas-fir. J. Forestry 77:480-483.

Ohmann, J. L., W.C. McComb, and A.A. Zumrawi. 1994. Wildl. Soc. Bull. 22:607-620..

Purcell, K. 1995. Reproductive strategies of open- and cavity-nesting birds. Dissertation for University of Nevada, Reno.

Purcell, K. L. and J. Verner. Life history traits and nest site characteristics of open- and cavity-nesting birds in oak-pine woodlands. Dissertation for the University of Nevada, Reno.

Purcell, K. L. J. Verner and L. W. Orange. 1997. A comparison of the breeding ecology of birds nesting in boxes and tree cavities. Auk 114(4):646-656.

Robertson, D. 1985. Monterey Birds. Monterey Peninsula Audubon Society.

Robertson, D. and C. Tenet (eds.) 1993. Atlas of breeding birds of Monterey County. Monterey Peninsula Audubon Society.

Roberts, R.C. 1986. Preserving oak woodland bird species richness: suggested guidelines from geographical ecology. . In Proc., Symposium on multi-use management of California's hardwood resources [San Luis Obispo, CA, Nov. 12-14, 1986] USDA For. Serv. Gen. Tech. Rep., PSW-100, p. 190-196.

Sauer, J.R, J.E. Hines, G. Gough, I. Thomas, and B.G. Peterjohn. 1997. The North American Breeding Bird Survey results and analysis. Version 96.4 Patuxtent Wildlife Research Center, Laurel, MD.

Sheldon, F. H. and F. B. Gill. 1996. A reconsideration of songbird phylogeny, with emphasis on the evolution of titmice and their sylvioid relatives. Systematic Biology 45(4): 473-495.

Sibley, C. S. 1952. The birds of the south San Francisco Bay region. Unbound copy available at the Point Reyes Bird Observatory library.

Silkas, B., F. H. Sheldon, and F. B. Gill. 1996. Phylogeny of titmice (Paridae): I. Estimate of relationships among subgenera based on DNA-DNA hybridization. Journal of Avian Biology 27: 70-82.

Small, Arnold. 1994. California birds: their status and distribution. Ibis Publishing Co. Vista, CA. 342 pp.

Tietje, W. D. and J. K. Vreeland. 1997. Vertebrates diverse and abundant in well-structured oak woodland. California Agriculture 51(6):8-14.

Verner, J., K. L. Purcell, and J. G. Turner. 1997. Bird communities in grazed and ungrazed oak-pine woodlands at the San Joaquin Experimental Range. USDA Forest Service Gen. Tech. Rep. PSW-GTR-160. 381-390.

Verner, J. and L. V. Ritter. 1988. A comparison of transects and point counts in oak-pine woodlands of California. Condor 90:401-419.

Verner, J. and L. V. Ritter. 1985. A comparison of transects and point counts in oak-pine woodlands of California. Condor 87:47-68.

Wilson, R.A., P. Manley and B.R. Noon. 1990. Covariance patterns among birds and vegetation in a California oak woodland. In Proc., Symposium on oak woodlands and hardwood rangeland management (Davis, CA Oct.31-Nov 2 1990). ] USDA For. Serv. Gen. Tech. Rep., PSW-126, p. 126-135.

Williams, P. L. and W. D. Koenig. 1980. Water dependence of birds in a temperate oak woodland. Auk 97:339-350.

Ziener, D. C., W. Laudenslayer, Jr., K. Mayer and M. White, eds. 1990. California’s Wildlife, vol. 2, California Department of Fish and Game, Sacramento, CA. 732 pp.


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