Summary of Bird Survey and Banding Results at 

W.L. Finley National Wildlife Refuge, 1998–2008

By Joan Hagar

Open-File Report 2012-1223

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

KEN SALAZAR, Secretary

U.S. Geological Survey

Marcia K. McNutt, Director

U.S. Geological Survey, Reston, Virginia: 2012

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Suggested citation:

Hagar, Joan, 2012, Summary of bird-survey and banding results at W.L.Finley National Wildlife Refuge, 1998–2008: 

U.S. Geological Survey Open-File Report 2012-1223, 12 p.

Any use of trade, product, or firm names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from 

the individual copyright owners to reproduce any copyrighted material contained within this report.

Photograph on title page is a Common Yellowthroat at Finley National Wildlife Refuge, Oregon by Joe Staff.
iii

Contents

Introduction.....................................................................................................................................................................1

Methods..........................................................................................................................................................................2

Study Site ...................................................................................................................................................................2

MAPS Banding and Breeding Status Determination...................................................................................................2

Point Counts ...............................................................................................................................................................2

Results and Discussion ..................................................................................................................................................3

Mist-Netting.................................................................................................................................................................3

Breeding Birds ............................................................................................................................................................5

Point Count Surveys ...................................................................................................................................................7

Conclusion......................................................................................................................................................................9

Acknowledgments ..........................................................................................................................................................9

References Cited..........................................................................................................................................................10

Appendix 1. Common and scientific names of birds and plants mentioned in the text and tables................................11

Figure

Figure 1. Composition of bird assemblage at Pigeon Butte comprised of 10 most abundant species during (A) 

Baseline phase (1994–96); (B) Pre-restoration phase (2004, 2007); and (C) Post-restoration phase (2008). ..............8

Tables

Table 1. Comparison of capture rate (birds per 100 net hours) by species across six breeding seasons at Pigeon 

Butte before oak woodland restoration (1998–2002, and 2007), and one season post-restoration (2008). ..................4

Table 2. Breeding status of all birds detected at Pigeon Butte banding station during operation of mist-nets.........5

Table 3. Average number (and standard error) of birds per visit per point count station (abundance index) for 

common species at Pigeon Butte. .................................................................................................................................9
iv

Conversion Factors

SI to Inch/Pound

Multiply By To obtain

millimeter (mm) 0.03937 inch (in.)

meter (m) 3.281 foot (ft)

hectare (ha) 2.471 acre (acre)
1

Summary of Bird Survey and Banding Results at 

W.L. Finley National Wildlife Refuge,1998–2008

By Joan Hagar

Introduction

With some of the best remaining examples of oak habitats in the Willamette Valley, the 

Willamette Valley National Wildlife Refuge Complex (WVNWRC) has been implementing restoration 

efforts to reverse the successional trend towards Douglas-fir and maple that is threatening existing oak 

woodlands. The restoration work has been considered a model for other public and private efforts within 

the Willamette Valley, and has been showcased through the Oregon Oak Communities Working Group 

(www.oregonoaks.org). Although many oak restoration projects have been initiated over the last several 

years, and grant recipients typically identify wildlife species that are likely to benefit from their project, 

measures of success have not included the actual response of wildlife, such as a change in the probability 

of species occurrence or abundance. Monitoring in the WVNWRC has so far been limited to vegetative 

and structural changes within the plant community. 

Hagar and Stern (2001) identified bird species occurring in Willamette Valley oak woodlands that 

might be expected to benefit from such restoration efforts, including an endemic subspecies of the Whitebreasted Nuthatch (see Appendix 1 for scientific names of bird and plant species listed in this document),

and the Acorn Woodpecker, both of which are species of concern in Oregon. However, empirical data 

documenting responses of bird assemblages to restoration actions are needed. The goal of this study was

to document the effects of a restoration project in an Oregon White Oak woodland on Pigeon Butte in the 

W.L. Finley National Wildlife Refuge. Restoration treatments on Pigeon Butte include the removal of 

shade-tolerant tree species (primarily big-leaf maple and Douglas-fir) to reduce competition with oak 

trees and to return the stand to a more open structure. The objectives of this ongoing study are to compare 

abundance, survival, and productivity of diurnal songbird species before and after application of these 

restoration treatments. Monitoring these vital rates will provide crucial information about the effects of 

management on survival and productivity (DeSante and Rosenberg, 1998). Therefore, a constant-effort 

mist-netting project was continued in 2007 and 2008 that had previously collected songbird demographic 

data at Pigeon Butte from 1998 to 2002. Point-count surveys were conducted in the woodland to build on 

historical data available for the site (Anderson, 1970; Hagar and Stern, 2001). The data reported here 

represent 5 years of point count surveys and 6 years of banding before restoration treatment, but only one 

post-treatment sampling season. Continued monitoring of the bird population is recommended to 

determine both short-term effects and long-term trends following the habitat alterations that result from 

restoration treatment.
2

Methods

Study Site

William L. Finley National Wildlife Refuge lies at the base of the foothills of the Coast Range on

the western edge of the central Willamette Valley, Oregon. Pigeon Butte is located at the highest point on 

the refuge, and is covered by a dense woodland dominated by Oregon White Oak. Bigleaf Maple and 

Douglas-fir also were common trees in the woodland. Common understory shrubs included Snowberry, 

Poison Oak, Hazel, Indian Plum, Trailing Blackberry, and Swordfern. The restoration was applied to 

approximately 4 ha in the southeastern corner of the 28-ha oak woodland on Pigeon Butte in the fall of 

2007. The restoration treatment consisted of mechanical removal of maple and other non-oak trees, 

followed by herbicide applications to stumps, mowing, and seeding native grasses and forbes.

MAPS Banding and Breeding Status Determination

I followed protocols established by the Institute for Bird Populations (IBP) for operation of 

Monitoring Avian Productivity and Survivorship (MAPS) Program stations (Institute for Bird 

Populations, 2001). I captured birds on 8 days between May 21 and August 10 in each year. I used twelve 

12.0 × 2.6 m, 30 mm mesh mist nets spaced throughout the eastern one-third of the stand to capture birds. 

Nets were set up at dawn and checked at least every 50 minutes for approximately 6 hours. I recorded the 

species, sex, and age of each bird captured using guidelines described in Pyle (1997). All species except 

hummingbirds were banded with a USGS-issued metal band with a unique number. In addition, all bird 

species observed at the site were recorded and their activity noted according to standard protocol 

established by IBP (Institute for Bird Populations, 2001). I used this information to determine the 

breeding status of all birds observed. All capture data and breeding bird species lists were submitted to the 

IBP to contribute to their regional and continent-wide bird population monitoring programs.

To evaluate trends in capture rates of birds across years, I calculated the number of individuals 

captured for each species in each season by summing the number of unique individuals (excluding withinseason recaptures) that were captured across the 8 sample days, and dividing by total net hours (1 net hour 

= one 12-m net operated for 1 hour). Because Rufous Hummingbirds were not banded, I could not keep 

track of unique individuals; therefore, I used the total number of captures of hummingbirds to calculate 

capture rates for this species. All capture rates are reported as birds per 100 net hours.

Point Counts

I conducted point count surveys on four dates between June 2 and June 26, 2008. Point counts 

were conducted at five stations originally established by Hagar and Stern in 1994 (Hagar and Stern, 2001) 

and subsequently surveyed in 1995, 1996, 2004, and 2007. At each station, I recorded all birds observed

within a 10-min count period, and estimated the distance to each bird. All surveys were conducted within 

4 hours of sunrise on days without rain or wind. 

I combined point count data from all 6 years of surveys to evaluate changes in the songbird 

community over time. I grouped the survey years into three phases: (1) 1994–96 comprised the “Baseline” 

survey phase, and represented the bird assemblage in an unmanaged, closed-canopy oak woodland; (2) 

2004 and 2007 comprised the “Pre-treatment” survey phase, and also represented the bird assemblage in 

an unmanaged, closed-canopy oak woodland, but a decade after the first phase, and 1–4 years before 

implementation of restoration treatment; (3) 2008 represents the first breeding season after restoration 

treatment. 
3

I calculated an index to abundance for commonly occurring species and all species combined 

(total abundance) by averaging the number of observations per point count station per visit within each 

year. I used analysis of variance (ANOVA) (Proc GLM in SAS ver. 9.2) to compare abundance indices 

among the three phases of the study for total abundance and 13 species that were observed in at least 40

percent of the sample units (one sample unit was defined as one visit to one station within a year). Species 

that occurred less frequently were not amenable to ANOVA analysis because of the large number of null 

observations.

Results and Discussion

Mist-Netting 

A cumulative total of 1,193 birds captured over 7 years of mist-netting (1998–2002, 2007–08) 

represented 38 species. Many of these species experience high background levels of annual variation in 

population size. In addition, the response of some species to the initial disturbance caused by restoration 

activities may not accurately indicate longer term responses to resulting habitat changes. Therefore, 

multiple years of post-treatment data are needed to confirm responses of each species to restoration 

treatment. Furthermore, the results reported here represent data collected at a single restoration site. 

Replicated research in woodlands throughout the region is needed to confirm and better understand the 

mechanisms underlying the responses of all species to restoration treatments. For these reasons, the initial 

results reported below do not represent conclusive responses to restoration treatment for any species. 

The capture rate of 14 species increased in 2008 after restoration treatment, relative to their 6-year 

pre-treatment average capture rates (table 1). Four of these species (White-breasted Nuthatch, Cedar

waxwing, Western Wood-pewee, and Lazuli Bunting) were among those identified by Hagar and Stern 

(2001) as likely to respond positively to removal of conifers to restore oak woodland. Capture rates of 

Spotted Towhee and Purple Finch, species that use oak woodlands as primary habitat in western Oregon 

(Hagar and Stern, 2001), also increased after restoration treatment. Increases in capture rates of Spotted 

Towhees and Western Tanagers were corroborated by the point count data, which indicated increased 

abundance of these species after restoration treatment (see Point Count Surveys, below).

The total capture rate of all species combined decreased by almost 7 birds per 100 net hours after 

treatment. Among the species that had lower capture rates after treatment were understory-associated 

species, such as Bewick’s Wren, Common Yellowthroat, Swainson’s Thrush, Pacific Wren, and Orangecrowned Warbler (table 1). The treatment involved mechanical activity that reduced understory cover. A 

decrease in the capture rate of Swainson’s Thrush and Pacific Wren after treatment is consistent with the 

association of both species with dense, closed-canopy forest. In contrast, Bewick’s Wren and Blackcapped Chickadee are oak-woodland associated species that were predicted to ultimately benefit from oak 

restoration (Hagar and Stern, 2001). However, the decreases in capture rates of these species from pre- to 

post-treatment may reflect an immediate negative response to disturbance. It is possible that these species 

will accrue a long-term benefit from restoration treatment after the stand recovers from the initial 

disturbance, so continued monitoring is recommended. An additional five species identified by Hagar and 

Stern (2001) as likely to respond positively to removal of conifers to restore oak woodland (Western 

Scrub Jay, House Wren, Cassin’s Vireo, American Goldfinch and Downy Woodpecker) also contrarily 

had decreases in capture rates. However, unlike the Bewick’s Wren and Black-capped Chickadee, these 

species were only irregularly captured during the pre-treatment seasons, and decreases from pre- to posttreatment were minor (less than 0.5 birds per 100 net hours; table 1). Therefore, although these species did 

not show an immediate positive response to treatment, I cannot conclude that they were negatively 

affected by the treatment because of the high variability in capture rates.
4

Table 1. Comparison of capture rate (birds per 100 net hours) by species across six breeding seasons at Pigeon 

Butte before oak woodland restoration (1998–2002, and 2007), and one season post-restoration (2008). 

[Species are listed in order of difference in average capture rate between post- and pre-treatment (Diff), from positive 

(indicating increase after treatment) to negative (decrease after treatment). Species in bold-face font were predicted by Hagar 

and Stern (2001) as likely to respond positively to conifer removal from oak woodland. Pre-trt ave is the average capture rate 

for 6 years pre-restoration treatment]

Species 1998 1999 2000 2001 2002 2007

Pre-trt 

ave 2008 Diff

Rufous Hummingbird 0.22 0.81 1.89 3.02 1.91 0.98 1.47 3.49 2.02

Western Tanager 1.52 0.81 0.52 0.57 0.70 1.96 1.01 1.94 0.93

Spotted Towhee 2.39 2.82 2.93 3.58 3.30 3.92 3.16 4.08 0.92

White-br. Nuthatch 0.00 0.00 0.00 0.19 0.17 0.00 0.06 0.58 0.52

Cedar Waxwing 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.39 0.39

Western Wood-pewee 0.22 0.20 0.86 0.57 0.52 0.59 0.49 0.78 0.28

Hairy Woodpecker 0.22 0.00 0.17 0.19 0.00 0.20 0.13 0.39 0.26

Red-breasted Sapsucker 0.00 0.00 0.00 0.38 0.35 0.20 0.15 0.39 0.23

Hutton's Vireo 0.22 0.00 0.17 0.19 0.17 0.39 0.19 0.39 0.20

Red-breasted Nuthatch 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.19 0.19

Dark-eyed Junco 0.22 0.00 0.17 0.19 0.17 0.59 0.22 0.39 0.16

Purple Finch 0.65 0.60 0.69 1.70 0.70 0.78 0.85 0.97 0.12

Brown Creeper 0.87 0.60 2.24 0.75 0.70 1.18 1.06 1.16 0.11

Lazuli Bunting 0.00 0.20 0.34 0.00 0.00 0.00 0.09 0.19 0.10

American Robin 1.52 1.41 2.41 1.89 1.74 1.57 1.76 1.75 -0.01

Pacific-slope Flycatcher 0.22 0.60 0.17 0.19 0.70 1.76 0.61 0.58 -0.02

Steller's Jay 0.00 0.00 0.17 0.00 0.00 0.00 0.03 0.00 -0.03

Northern Flicker 0.00 0.00 0.00 0.00 0.17 0.00 0.03 0.00 -0.03

Willow Flycatcher 0.00 0.00 0.00 0.00 0.17 0.00 0.03 0.00 -0.03

Western Scrub Jay 0.00 0.00 0.00 0.19 0.00 0.00 0.03 0.00 -0.03

House Wren 0.00 0.20 0.00 0.00 0.00 0.00 0.03 0.00 -0.03

Yellow-breasted Chat 0.00 0.20 0.00 0.00 0.00 0.00 0.03 0.00 -0.03

Cassin's Vireo 0.22 0.00 0.00 0.00 0.00 0.00 0.04 0.00 -0.04

Bushtit 0.00 0.00 0.00 0.38 0.00 0.00 0.06 0.00 -0.06

Black-headed Grosbeak 0.00 0.00 0.17 0.19 0.00 0.39 0.13 0.00 -0.13

American Goldfinch 0.00 0.00 0.00 0.75 0.00 0.00 0.13 0.00 -0.13

Brown-headed Cowbird 0.43 0.00 0.00 0.00 0.17 0.20 0.13 0.00 -0.13

Downy Woodpecker 0.43 0.00 0.86 0.00 0.17 0.00 0.24 0.00 -0.24

MacGillivray's Warbler 0.00 0.81 0.00 0.38 0.17 0.59 0.32 0.00 -0.32

Song Sparrow 2.17 1.81 2.41 2.64 0.70 0.78 1.75 1.16 -0.59

Bl.-throated gray Warbler 0.87 0.20 0.52 0.94 1.22 0.39 0.69 0.00 -0.69

Wilson's Warbler 1.30 1.21 0.17 0.57 0.52 0.78 0.76 0.00 -0.76

Bewick's Wren 1.74 2.42 1.89 2.26 2.26 3.92 2.42 1.36 -1.06

Common Yellowthroat 0.43 0.81 2.41 1.51 0.52 0.98 1.11 0.00 -1.11

Swainson's Thrush 6.08 6.05 4.48 7.55 5.39 7.84 6.23 5.05 -1.18

Black-capped Chickadee 1.30 1.61 1.89 1.70 1.91 1.96 1.73 0.39 -1.34

Pacific Wren 1.09 1.81 2.41 1.51 0.70 0.59 1.35 0.00 -1.35

Orange-crowned Warbler 7.38 5.24 4.82 3.96 4.00 4.31 4.95 0.97 -3.98

Total (All spp. combined) 31.68 30.45 34.78 37.92 29.22 36.85 33.48 26.58 -6.90
5

Breeding Birds 

Of the 81 species observed since monitoring began in 1998 (table 2), 28 breed, or likely breed,

every year at Pigeon Butte. We observed 60 species of birds at the site during 2008. New species 

recorded in 2008 were Cooper’s Hawk, Peregrine Falcon, and Western Meadowlark. A Cooper’s 

Hawk was observed on two banding dates (12 and 24 June, 2008) and during point counts, suggesting 

that this species may have been using the Pigeon Butte woodland for nesting. 

Table 2. Breeding status of all birds detected at Pigeon Butte banding station during operation of mist-nets.

[Breeding status codes: B = Breeding: Known or suspected to have at least one pair breeding within the station; L = Likely 

Breeding: Some evidence of breeding, but some uncertainty to breeding status due to infrequent detection; T = Transient: 

Species was infrequently observed and is likely moving through the site; M = Migrant: Site not within normal breeding 

range of the species. Birds observed likely are migrants. – indicates that a species was not detected. Species are listed in 

phylogenetic order. Regularly breeding species are marked with *]

Breeding Status

Species 1998 1999 2000 2001 2002 2007 2008

Great Blue Heron - - T T T T -

Turkey Vulture T T T L L T T

Canada Goose - T T T T T T

Osprey - - T T T T T

Bald Eagle - - - T - T -

Northern Harrier T T T T - - T

Sharp-shinned Hawk T - - - - T -

Cooper’s Hawk - - - - - - T

Red-tailed Hawk T L T L T T L

American Kestrel - - T L T - T

Peregrine Falcon - - - - - - M

Ruffed Grouse T - - - - - -

Wild Turkey - - - - T - -

California Quail - - - - B T T

Northern Bobwhite - - - - T - -

Sandhill Crane - - - M - - -

Killdeer - T T T T - T

Greater Yellowlegs - - - - - M -

Band-tailed Pigeon T T T T L L L

Mourning Dove L T L L L B L

Great-horned Owl T - T T - L -

Vaux's Swift - - - T T - -

Rufous Hummingbird* B B B B B B B

Belted Kingfisher - - - T - - -

Red-breasted Sapsucker* B B B B B B B

Downy Woodpecker* B B B B B B L

Hairy Woodpecker* B L B B B B L

Northern Flicker T L T L B B L

Pileated Woodpecker - - - - L T T

Western Wood-pewee* B B B B B B B

Willow Flycatcher - T T T T - -

Pacific-slope Flycatcher* B B B B B B B

Cassin's Vireo* B T B B B B L

Hutton's Vireo* B L L B B B B

Warbling Vireo T T L T T - T
6

Breeding Status

Species 1998 1999 2000 2001 2002 2007 2008

Steller's Jay - - T B T T T

Scrub Jay* L B B B B B B

American Crow - L T T T L T

Common Raven T T T L T T T

Tree Swallow - L T T T T T

Violet-green Swallow T T T T T T T

Cliff Swallow - T - - T T T

Barn Swallow - T T L T T T

Black-capped Chickadee* B B B B B B B

Bushtit L - T B T B B

Red-breasted Nuthatch T L L T T B B

White-breasted Nuthatch* L B B B B B B

Brown Creeper* B B B B B B B

Bewick's Wren* B B B B B B B

House Wren - T L - - - T

Pacific Wren* B B B B B B B

Western Bluebird - - - T T - -

Swainson's Thrush* B B B B B B B

Hermit Thrush - - - M - - -

American Robin* B B B B B B B

Wrentit - T B B B B -

European Starling T L L B L T T

Cedar Waxwing* B L B B B B L

Orange-crowned Warbler* B B B B B B B

Yellow Warbler T T - - - - T

Black-throated gray Warbler* B B B B B B B

Townsend's Warbler - M - - - - -

MacGillivray's Warbler - T - T T T -

Common yellowthroat* B B B B B B B

Wilson's Warbler B B B B B T T

Yellow-breasted Chat - T T - - T T

Western Tanager* B B B B B B B

Spotted Towhee* B B B B B B B

Savannah Sparrow - L L - - - -

Song Sparrow* B B B B B B B

Golden-crowned Sparrow - M - - - - -

Dark-eyed Junco L - L T L B B

Black-headed Grosbeak* B B B B L B L

Lazuli Bunting* L B B B B B B

Western Meadowlark - - - - - - T

Brown-headed Cowbird* B B L B B B L

Northern Oriole - - T T T T T

Purple Finch* B B B B B B B

Pine Siskin - T T - - - -

American Goldfinch* L L B B B L L

Evening Grosbeak - T - - T - -
7

Point Count Surveys 

Species composition remained relatively stable throughout all phases of the study, based on 

point count data. The Spotted Towhee was the most abundant species during all phases of the study, 

comprising more than 11 percent of the individual birds observed (fig. 1). Swainson’s Thrush, Western 

Wood-pewee, and Orange-crowned Warbler also were among the four most abundant species recorded 

on point count surveys during the baseline (1994–96) and pre-treatment (2004, 2007) periods. After 

restoration treatment in 2008, the Western Tanager replaced Swainson's Thrush in the group of three

most abundant species (fig. 1). After restoration treatment in 2008, six species comprised more than 50

percent of observed individuals: Spotted Towhee (16 percent), Western Wood-pewee (15 percent), 

Western Tanager (6.5 percent), Swainson’s Thrush (6 percent), Black-throated Gray Warbler (5.5

percent), and Orange-crowned Warbler (5 percent).

Total abundance of all species combined remained consistent across all phases of the study at

an average of 15 birds per point count station per visit (table 3). The abundance of three species 

increased significantly from the baseline to the post-restoration phase (Pacific-slope Flycatcher, 

Spotted Towhee, and Western Tanager). The brush piles created by the restoration activities and the 

proliferation of blackberry following canopy opening probably favored habitat conditions for the 

Spotted Towhee. Tanagers also responded positively to the reduction in canopy density; this response 

is typical for the species (Hagar and others, 2004). However, as a species associated with dense midstory cover, the Pacific-slope flycatcher was not expected to respond positively to canopy removal. A 

spike in the capture rate in 2007 (table 1) may have indicated a productive year for this species. The 

high abundance we observed in 2008 may have been a carryover effect from the previous year’s 

productivity, rather than an effect of habitat change. 

We did not find statistical evidence for a decrease in the abundance of any species. However, 

Hagar and Stern (2001) hypothesized that abundance of the Pacific Wren may decrease after 

restoration treatments to remove cover in oak woodlands, so we examined the response of this species. 

Although the abundance of Pacific Wrens was too low to support statistical analysis, we did observe a 

decrease in the number of observations from an average of 10.3 (range: 9–11) per year during the 

baseline period to 3 observations after restoration treatment in 2008. This trend is consistent with the 

capture data from mist-netting (table 1).

Hagar and Stern (2001) also hypothesized that three species that are strongly associated with 

oak woodlands, the White-breasted Nuthatch, Cassin’s Vireo, and Lazuli Bunting may respond 

positively to treatments that reduce density of shade-tolerant tree species in oak woodlands. The 

abundance of all three of these species was too low to indicate any trends according to point count 

data, although capture rates from mist-net surveys indicated a positive response to the maple removal 

treatment by the White-breasted Nuthatch (table 1). A stronger response may be observed over time, as 

habitat conditions that favor these species (such as large-diameter oak boles and limbs for nuthatches, 

and thriving oak canopy for the vireo and bunting) develop following restoration treatment.
8

Figure 1. Composition of bird assemblage at Pigeon Butte comprised of 10 most abundant species during (A) 

Baseline phase (1994–96); (B) Pre-restoration phase (2004, 2007); and (C) Post-restoration phase (2008).

A

B

C
9

Table 3. Average number (and standard error) of birds per visit per point count station (abundance index) for 

common species at Pigeon Butte. 

[P is the probability associated with the test of the null hypothesis that abundance did not differ among phases of the study 

(ANOVA). Where P < 0.05 (bold font), different letters indicate significantly different abundance indices between phases 

(Baseline: 1996–98; Pre-restoration: 2004, 2007; Post-restoration: 2008)]

Baseline Pre-restoration Post-restoration P

Total (all species combined) 14.97 (0.68) 15.17 (0.73) 15.10 (1.10) 0.983

American Robin 0.63 (0.09) 0.45 (0.16) 0.60 (0.17) 0.605

Black-capped Chickadee 0.72 (0.17) 0.48 (0.17) 0.35 (0.19) 0.486

Black-throated Gray Warbler 0.49 (0.08) 0.62 (0.17) 0.90 (0.23) 0.168

Brown-headed Cowbird 0.43 (0.11) 0.58 (0.18) 0.35 (0.10) 0.694

Black-headed Grosbeak 0.38 (0.08) 0.30 (0.09) 0.25 (0.08) 0.702

Brown Creeper 0.64 (0.11) 0.60 (0.11) 0.55 (0.09) 0.915

Orange-crowned Warbler 1.14 (0.12) 1.00 (0.16) 0.80 (0.28) 0.472

Pacific-slope Flycatcher 0.46 (0.07)A 0.87 (0.16)B 1.00 (0.44)B 0.031

Purple Finch 0.56 (0.06) 0.83 (0.10) 0.65 (0.28) 0.138

Spotted Towhee 1.65 (0.13)A 1.98 (0.22)AB 2.65 (0.37)B 0.014

Swainson's Thrush 1.29 (0.10) 1.40 (0.18) 1.20 (0.29) 0.764

Western Tanager 0.53 (0.07)A 0.98 (0.07)B 1.20 (0.24)B <0.001

Western Wood-pewee 1.24 (0.13) 1.57 (0.27) 2.10 (0.71) 0.109

Conclusion

Overall, the results of the point counts and mist-netting indicate changes in the song-bird 

assemblage 1 year after restoration treatments in a portion of the Pigeon Butte woodland. Continued 

monitoring is necessary to distinguish the short-term effects of response to disturbance and annual 

variability in bird populations from longer term responses to habitat change. Continued surveys at 

Pigeon Butte, along with replicated surveys at other oak restoration projects in the Willamette Valley, 

are needed to provide information about bird response over expanded temporal and spatial scales.

Acknowledgments

Support for this project in 2008 was provided by a grant from the USGS Science Support 

Partnership program. Contributions have been received by Oregon Field Ornithologist’s and the 

Corvallis Audubon Society and its members in prior years. Jock Beall arranged the logistical support 

provided by the W.L. Finley National Wildlife Refuge.

I am grateful to Molly Monroe for her competent and faithful assistance with all aspects of the 

project, from clearing net lanes of poison oak and blackberry thickets, to handling, banding and 

identifying birds, and accurately recording banding data. Joaquin Acosta, Joe Fontaine, Ruth Jacobs, 

Matt Lee, Russ Namitz, Sally Shaw, Tom and Christina Snetsinger, Caleb Spiegel, Roberta Swift, and 

Billi Veber also provided valuable assistance and good company in the field. Jennifer Weikel helped to 

establish the Pigeon Butte station and helped to collect much of the early banding data.
10

References Cited

Anderson, S.H., 1970, The avifaunal composition of Oregon white oak stands: Condor, v. 72, p. 417–

423.

DeSante, D.F., and Rosenberg, D.K., 1998, What do we need to monitor in order to manage landbirds?,

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Appendix 1. Common and scientific names of birds and plants mentioned in the 

text and tables. 

Common Name Birds Scientific Name Birds

Acorn Woodpecker Melanerpes formicivorus

American Crow Corvus brachyrhynchos

American Goldfinch Spinus tristis

American Kestrel Falco sparverius

American Robin Turdus migratorius

Bald Eagle Haliaeetus leucocephalus

Band-tailed Pigeon Patagioenas fasciata

Barn Swallow Hirundo rustica

Belted Kingfisher Megaceryle alcyon

Bewick’s Wren Thryomanes bewickii

Black-throated gray Warbler Setophaga nigrescens

Black-capped Chickadee Poecile atricapillus

Black-headed Grosbeak Pheucticus melanocephalus

Brown Creeper Certhia americana

Brown-headed Cowbird Molothrus ater

Bushtit Aegithalidae

California Quail Callipepla californica

Canada Goose Branta canadensis

Cassin’s Vireo Vireo cassinii

Cedar Waxwing Bombycilla cedrorum

Cliff Swallow Petrochelidon pyrrhonota

Common Raven Corvus corax

Common Yellowthroat Geothlypis trichas

Cooper’s Hawk Accipiter cooperii

Dark-eyed Junco Junco hyemalis

Douglas-fir Pseudotsuga menziesii

Downy Woodpecker Picoides pubescebs

European Starling Sturnus vulgaris

Evening Grosbeak Coccothraustes vespertinus

Golden-crowned Sparrow Zonotrichia atricapilla

Great Blue Heron Ardea herodias

Greater Yellowlegs Tringa melanoleuca

Great-horned Owl Bubo virginianus

Hairy Woodpecker Picoides villosus

Hermit Thrush Catharus guttatus

House Wren Troglodytes aedon

Hutton’s Vireo Vireo huttoni

Killdeer Charadrius vociferus

Lazuli Bunting Passerina amoena

MacGillivray’s Warbler Geothlypis tolmiei

Mourning Dove Zenaida macroura

Northern Bobwhite Colinus virginianus

Northern Flicker Colaptes auratus

Northern Harrier Circus cyaneus

Northern Oriole Icterus galbula

Orange-crowned Warbler Oreothlypis celata

Osprey Pandion haliaetus

Pacific-slope Flycatcher Empidonax difficilis

Peregrine Falcon Falco peregrinus

Pileated Woodpecker Dryocopus pileatus
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Pine Siskin Carduelis pinu

Purple Finch Haemorhous purpureus

Red-breasted Nuthatch Sitta canadensis

Red-breasted Sapsucker Sphyrapicus ruber

Red-tailed Hawk Buteo jamaicensis

Ruffed Grouse Bonasa umbellus

Rufous Hummingbird Selasphorus rufus

Sandhill Crane Grus canadensis

Savanna Sparrow Passerculus sandwichensis

Sharp-shinned Hawk Accipiter striatus

Song Sparrow Melospiza melodia

Spotted Towhee Pipilo maculates

Steller’s Jay Cyanocitta stelleri

Swainson’s Thrush Catharus ustulatus

Townsend’s Warbler Setophaga townsendi

Tree Swallow Tachycineta bicolor

Turkey Vulture Cathartes aura

Vaux’s Swift Chaetura vauxi

Violet-green Swallow Tachycineta thalassina

Warbling Vireo Vireo gilvus

Western Bluebird Sialia mexicana

Western Meadowlark Sturnella neglecta

Western Scrub Jay Aphelocoma californica

Western Tanager Piranga ludoviciana

Western Wood-pewee Contopus sordidulus

White-breasted Nuthatch Sitta carolinensis (subspecies aculeata)

Wild Turkey Meleagris gallopavo

Willow Flycatcher Empidonax traillii

Wilson’s Warbler Cardellina pusilla

Pacific Wren Troglodytes pacificus

Wrentit Chamaea fasciata

Yellow Warbler Setophaga petechia

Yellow-breasted Chat Icteria virens

Common Name Plants Scientific Name Plants

Blackberry Rubus

Bigleaf Maple Acer macrophyllum

Douglas-fir Pseudotsuga menziesii

Indian Plum Oemleria cerasifomis

Hazel Corylus cornuta

Oak species Quercus

Oregon White Oak Quecus garryanna

Poison Oak Toxicodendron diversilobum

Snowberry Symphocarpus albus

Swordfern Polystichum munitum

Trailing Blackberry Rubus ursinus