Oregon Breeding Bird Atlas Update

Introduction to the Update to the Oregon Breeding Bird Atlas

Excerpted from Adamus, P.R. and R. Scalf. 2021. Possible Changes in Breeding Ranges of Oregon Birds, 1990s through 2019. Oregon Birds [47.1, page numbers TBD]

The following maps are intended as a partial update to the Oregon Breeding Bird Atlas, using only non-systematic data from eBird and other digital sources. The OBBA provided the first systematic statewide baseline for our state’s avifauna. Sponsored by the Oregon Birding Association (OBA, previously called Oregon Field Ornithologists), the project involved hundreds of volunteers from 1995 to 1999, and is documented with species maps elsewhere on this website.

The purpose for this update was to produce a set of species maps that depict more recent distribution of each species using the same coarse-scale hexagonal grid used by the OBBA. The OBBA used a hexagonal grid because it has the least distortion when covering a spherical surface such as the earth. Each of the 432 hexagons covering all or part of the state has an area of 250 square miles and a diameter of approximately 20 miles.

In each grid unit, we applied one of three colors:

•             [Pink]: Found only during 1995–1999 OBBA (“BBA only”)
•             [Tan]: Found during 1995-1999 OBBA and again during a 2000-2019 breeding season (“Replicated”)
•             [Green]: Found only during a 2000-2019 breeding season (“New”)
•             [Blank]: No reports of presence during the normal breeding period of the species

Where evidence of confirmed breeding was reported, we applied these codes:

•             A: Breeding confirmed during 1995-1999 OBBA
•             N: Breeding confirmed during a 2000-2019 breeding season
•             AN: Breeding confirmed at least once during both periods

Also, we used the letter Q to denote records in which habitat suitable for the species is unlikely to exist in the hexagon and the hexagon is believed to be outside of the species’ normal Oregon breeding range. It is not possible to tell if these occurrences represent vagrants, early or late migrants, non-breeding individuals, or individuals pioneering new territory. Note that while the OBBA assigned various breeding behaviors to one of three levels (possible, probable, or confirmed), data indicating probable breeding could not be parsed from possible breeding in the data used in this analysis and so are represented simply by the absence of any letter code in the grid unit.

Data Sources

The largest source of post-OBBA digital data was eBird. We obtained all reports from Oregon spanning the period of January 2000 through December 2019 that eBird classifies as “vetted.” The download included all records from the Oregon 2020 Project (Robinson 2020). Extensive digital records were also obtained from 1) the Avian Knowledge Network (AKN), which archives many surveys of birds by government agencies; 2) the Point Observation Database (PODS) database maintained by the Oregon Institute for Natural Resources; and (3) the Central Oregon Bird Database compiled by Chuck Gates. In addition, we manually searched all issues of Oregon Birds from 2000 to 2019 for reports of confirmed breeding but not for reports during the breeding season that did not mention breeding.

Nonetheless, we could not include all relevant data sources. Digital data from major sources such as BirdNotes, the North American Breeding Bird Survey (BBS), and the OBOL and COBOL listservs were not included. In some cases that was due to the locational uncertainty of much of those data. We did not include non-digital sources such as Audubon chapter newsletters and notes kept by individual birders due to the considerable effort required to extract and digitize that information.

Methods

To allow comparison with the original OBBA data, a geographic information system (GIS) was used to determine the hexagon associated with the geographic coordinates of each downloaded record. It is known that coordinates of some records had been inaccurately recorded, but it is assumed this proportion is small enough relative to the scale of this analysis to not significantly affect the overall purpose of this analysis. For eBird data, reports of “traveling counts” longer than 15 kilometers (the length of one of an OBBA hexagon’s six sides) were excluded from the analysis due to their potential to span multiple hexagons. Where a record from a non-eBird data source lacked coordinates but contained a named location, searching the location in Google Earth with the hexagon grid overlay in place in most instances allowed its hexagon number to be assigned with confidence. Some popular eBird locations had thousands of records. To avoid overwhelming database and GIS software, each unique set of coordinates was found and assigned an identifier. All unique coordinates were then overlaid with the atlas grid and linked back to the millions of eBird records using a one-to-many database relate.

Like other breeding bird atlases, the OBBA volunteers categorized each breeding season observation as either a) confirmed breeding, b) probable breeding, or c) possible breeding. Standardized criteria for these are described in Smith (1991) and in eBird metadata. However, for the comparison described herein, we categorized records simply as “confirmed breeding” or “all other reports from a species’ usual breeding season in Oregon.” To identify confirmed breeding, we selected reports noting strong evidence of breeding (in the eBird download they were coded C4, or coded C3 with a nest reported) as well as records in which the Comments for that record contained these keywords: nest*, fledg*, baby, babies, young*. We then reviewed keyword-selected records individually and placed the ones wrongly selected by the automated search in the “all others” category. Those records were mapped but no breeding was denoted by application of our “N” code. A surprising proportion of eBird records document breeding in the Comments section without also applying the relevant breeding code.

We excluded records if 1) the observation was far outside of a species’ known range and habitat suitable for the species is unlikely to exist at those locations, or 2) the observation date did not fall within the species’ known breeding period in Oregon (Adamus 2020; Marshall et al. 2003) unless a nest or other strong evidence of breeding was reported. For both 1 and 2, some judgment calls were necessary. These were based on the author’s years of experience birding in all Oregon counties and were complemented by that of two individuals of similar experience (Paul Sullivan and Craig Miller) as well as by Joel Geier who commented specifically on records from Wheeler County and for Willamette Valley prairie species. These individuals reviewed the maps and recommended, for mapping purposes, the exclusion or qualification (by using the Q code) of a small number of records that they believed were likely to represent misidentifications, vagrants, or transient migrants rather than likely breeders. None of the original OBBA records depicted in the maps were second-guessed at this time because they had been reviewed and edited by regional bird experts prior to publication of the OBBA.

Another, albeit smaller, source of error is the misapplication of breeding codes by eBird users. For example, one Tufted Duck report from Oregon contained a FL code (for fledgling), indicating a likely misunderstanding of that code, given the fact that the known breeding range for the species is thousands of miles from Oregon. We attempted to flag such reports and exclude them unless a detailed and credible explanation had been provided.

Acknowledgments

We thank John Alexander and Ellie Armstrong (Klamath Bird Observatory) for facilitating access to selected data in their Avian Knowledge Network; Elizabeth Gaines (Oregon Biodiversity Information Center) for sharing data from their PODS database; and Chuck Gates (East Cascades Audubon Society) for sharing the database of central Oregon bird observations. For the eBird data, we thank the Cornell Laboratory of Ornithology and all the birders who contribute their observations to it.

Literature Cited

• Adamus, P.R. 2020. A compilation of breeding dates for Oregon species. Oregon Birds 46(2):101–108.
• Adamus, P.R., K. Larsen, G. Gillson, and C.R. Miller. 2001. Oregon Breeding Bird Atlas. Oregon Field Ornithologists, P.O. Box 10373, Eugene, OR 97440. Available at: https://oregonbirding.org/wp-content/uploads/2020/bbs/
• eBird Basic Dataset. Version: EBD_relJan2020. Cornell Lab of Ornithology, Ithaca, New York. January 2020.
• Marshall, D.B., M.G. Hunter, and A. Contreras. 2003. Birds of Oregon: a general reference. Corvallis, Oregon: Oregon State University Press.
• Smith, C. 1991. Handbook for Atlasing North American Breeding Birds. North American Ornithological Atlas Committee. Available at: https://www.bsc-eoc.org/norac/index.jsp?targetpg=atlascont

Table 1. Number of hexagons in which species was found only during 1995–1999 OBBA (“BBA only”), found only during a 2000-2019 breeding season (“New”), and found during 1995-1999 OBBA and again during a 2000-2019 breeding season (“Replicated”)

Table 2. Average abundance index from Oregon BBS routes during the 5 BBA years compared to BBS routes during a more recent 5 year period. Sorted from smallest to largest ratio, potentially suggesting the greatest to least declines. Number and location of BBS routes varies somewhat annually with unknown influence on trends analysis.

Table 1

Number of hexagons in which species was found only during 1995–1999 OBBA (“BBA only”), found only during a 2000-2019 breeding season (“New”), and found during 1995-1999 OBBA and again during a 2000-2019 breeding season (“Replicated”)

Species	BBA only	New	Replicated	Total
Acorn Woodpecker	4	33	48	85
Allen’s Hummingbird	9	4	10	23
American Avocet	20	60	83	163
American Bittern	20	61	52	133
American Coot	29	83	195	307
American Crow	15	74	299	388
American Dipper	37	66	152	255
American Goldfinch	29	76	268	373
American Kestrel	31	32	354	417
American Pipit	5	8	4	17
American Redstart	5	5	1	11
American Robin	26	7	397	430
American Three-toed Woodpecker	19	28	28	75
American White Pelican	9	95	44	148
American Wigeon	42	71	93	206
Anna’s Hummingbird	7	108	70	185
Ash-throated Flycatcher	36	67	108	211
Bald Eagle	9	128	221	358
Band-tailed Pigeon	1	42	122	165
Bank Swallow	26	112	116	254
Barn Owl	56	70	109	235
Barn Swallow	25	30	352	407
Barred Owl	25	60	93	178
Barrow’s Goldeneye	5	22	25	52
Belted Kingfisher	62	29	283	374
Bewick’s Wren	7	96	136	239
Black Oystercatcher	1	4	19	24
Black Phoebe	0	89	22	111
Black Rosy-Finch	0	2	1	3
Black Swift	9	14	2	25
Black Tern	8	52	40	100
Black-backed Woodpecker	21	40	90	151
Black-billed Magpie	18	40	222	280
Black-capped Chickadee	46	48	213	307
Black-chinned Hummingbird	29	100	49	178
Black-chinned Sparrow	3	0	0	3
Black-crowned Night-Heron	33	51	68	152
Black-headed Grosbeak	29	45	300	374
Black-necked Stilt	8	65	47	120
Black-throated Gray Warbler	40	71	178	289
Black-throated Sparrow	26	26	36	88
Blue Grosbeak	1	0	0	1
Blue-gray Gnatcatcher	7	63	23	93
Blue-winged Teal	37	96	77	210
Bobolink	10	12	21	43
Boreal Owl	4	5	1	10
Brandt’s Cormorant	4	3	19	26
Brewer’s Blackbird	27	18	371	416
Brewer’s Sparrow	31	65	187	283
Broad-tailed Hummingbird	22	9	1	32
Brown Creeper	20	46	236	302
Brown-headed Cowbird	48	11	360	419
Bufflehead	28	107	79	214
Bullock’s Oriole	33	73	249	355
Burrowing Owl	38	23	56	117
Bushtit	24	98	187	309
California Gull	23	41	75	139
California Quail	53	40	301	394
California Scrub-Jay	7	112	133	252
California Towhee	1	15	12	28
Calliope Hummingbird	53	52	96	201
Canada Goose	30	59	299	388
Canada Jay	30	48	157	235
Canvasback	21	30	35	86
Canyon Wren	36	58	89	183
Caspian Tern	19	32	79	130
Cassin’s Auklet	1	18	4	23
Cassin’s Finch	36	51	181	268
Cassin’s Vireo	22	56	255	333
Cattle Egret	2	10	2	14
Cedar Waxwing	20	87	252	359
Chestnut-backed Chickadee	9	28	151	188
Chipping Sparrow	52	38	294	384
Chukar	43	25	119	187
Cinnamon Teal	58	44	184	286
Clark’s Grebe	10	91	35	136
Clark’s Nutcracker	24	49	128	201
Clay-colored Sparrow	0	4	0	4
Cliff Swallow	34	28	346	408
Common Goldeneye	5	4	2	11
Common Loon	9	11	8	28
Common Merganser	38	77	209	324
Common Murre	1	3	21	25
Common Nighthawk	38	31	345	414
Common Poorwill	60	89	75	224
Common Raven	8	14	410	432
Common Yellowthroat	20	107	206	333
Cooper’s Hawk	54	93	204	351
Costa’s Hummingbird	0	2	0	2
Dark-eyed Junco	22	26	315	363
Double-crested Cormorant	18	108	127	253
Downy Woodpecker	47	51	240	338
Dusky Flycatcher	45	71	216	332
Dusky Grouse	19	17	40	76
Eared Grebe	17	64	56	137
Eastern Kingbird	30	64	89	183
Eastern Phoebe	1	0	0	1
Eurasian Collared-Dove	0	338	0	338
European Starling	24	34	350	408
Evening Grosbeak	52	48	171	271
Ferruginous Hawk	33	62	85	180
Flammulated Owl	47	38	37	122
Fork-tailed Storm-Petrel	3	0	3	6
Forster’s Tern	11	52	49	112
Fox Sparrow	43	55	107	205
Franklin’s Gull	3	35	15	53
Gadwall	36	93	133	262
Glaucous-winged Gull	1	24	19	44
Golden Eagle	57	45	238	340
Golden-crowned Kinglet	23	41	234	298
Golden-crowned Sparrow	2	3	1	6
Grasshopper Sparrow	19	54	31	104
Gray Catbird	19	52	19	90
Gray Flycatcher	30	58	144	232
Gray Partridge	22	26	45	93
Gray-crowned Rosy-Finch	1	9	7	17
Great Blue Heron	34	63	262	359
Great Egret	6	159	61	226
Great Gray Owl	73	8	7	88
Great Horned Owl	70	44	287	401
Greater Sage-Grouse	83	11	33	127
Greater Scaup	2	0	0	2
Greater Yellowlegs	2	1	0	3
Great-tailed Grackle	0	25	3	28
Green Heron	13	50	81	144
Green-tailed Towhee	45	60	119	224
Green-winged Teal	67	80	155	302
Hairy Woodpecker	11	27	301	339
Hammond’s Flycatcher	10	82	197	289
Harlequin Duck	10	22	10	42
Hermit Thrush	25	58	227	310
Hermit Warbler	7	30	146	183
Hooded Merganser	26	83	80	189
Horned Grebe	10	35	10	55
Horned Lark	26	45	215	286
House Finch	45	60	288	393
House Sparrow	27	57	250	334
House Wren	41	34	319	394
Hutton’s Vireo	4	19	122	145
Indigo Bunting	0	15	1	16
Juniper Titmouse	1	17	1	19
Killdeer	45	23	344	412
Lark Bunting	0	1	0	1
Lark Sparrow	22	93	164	279
Lawrence’s Goldfinch	0	1	0	1
Lazuli Bunting	33	90	264	387
Leach’s Storm-Petrel	5	1	2	8
Least Bittern	1	0	0	1
Least Flycatcher	8	27	2	37
Lesser Goldfinch	8	169	95	272
Lesser Scaup	35	49	84	168
Lewis’s Woodpecker	36	87	95	218
Lincoln’s Sparrow	17	116	99	232
Loggerhead Shrike	26	54	151	231
Long-billed Curlew	21	63	114	198
Long-eared Owl	69	63	38	170
MacGillivray’s Warbler	38	50	249	337
Mallard	35	24	363	422
Marbled Murrelet	12	8	27	47
Marsh Wren	20	86	118	224
Merlin	27	25	3	55
Monk Parakeet	1	2	1	4
Mountain Bluebird	32	36	217	285
Mountain Chickadee	29	39	200	268
Mountain Quail	42	55	148	245
Mourning Dove	28	30	365	423
Mute Swan	0	7	1	8
Nashville Warbler	37	73	116	226
Northern Bobwhite	9	5	0	14
Northern Flicker	32	3	385	420
Northern Goshawk	65	59	112	236
Northern Harrier	32	54	266	352
Northern Mockingbird	8	67	9	84
Northern Pintail	45	68	91	204
Northern Pygmy-Owl	63	28	185	276
Northern Rough-winged Swallow	37	58	282	377
Northern Saw-whet Owl	81	64	75	220
Northern Shoveler	27	100	122	249
Northern Waterthrush	5	12	5	22
Oak Titmouse	6	6	16	28
Olive-sided Flycatcher	24	62	229	315
Orange-crowned Warbler	36	72	250	358
Osprey	27	76	250	353
Pacific Wren	22	48	190	260
Pacific-slope Flycatcher	28	34	256	318
Pelagic Cormorant	1	3	21	25
Peregrine Falcon	34	152	75	261
Pied-billed Grebe	21	98	126	245
Pigeon Guillemot	1	2	22	25
Pileated Woodpecker	22	26	235	283
Pine Grosbeak	4	19	2	25
Pine Siskin	32	65	260	357
Pinyon Jay	8	20	23	51
Plumbeous Vireo	3	1	1	5
Prairie Falcon	59	43	177	279
Purple Finch	35	55	155	245
Purple Martin	3	53	57	113
Pygmy Nuthatch	23	48	99	170
Red Crossbill	31	54	225	310
Red-breasted Nuthatch	14	43	287	344
Red-breasted Sapsucker	9	52	161	222
Red-eyed Vireo	18	47	21	86
Redhead	28	58	69	155
Red-naped Sapsucker	55	39	93	187
Red-necked Grebe	2	17	2	21
Red-shouldered Hawk	2	137	29	168
Red-tailed Hawk	24	9	400	433
Red-winged Blackbird	30	21	353	404
Rhinoceros Auklet	0	10	14	24
Ring-billed Gull	20	105	87	212
Ring-necked Duck	28	90	104	222
Ring-necked Pheasant	43	40	157	240
Rock Pigeon	26	84	207	317
Rock Wren	34	70	249	353
Rose-breasted Grosbeak	0	25	0	25
Ruby-crowned Kinglet	57	53	103	213
Ruddy Duck	25	74	80	179
Ruffed Grouse	33	41	182	256
Rufous Hummingbird	31	51	256	338
Sage Thrasher	27	47	145	219
Sagebrush Sparrow	36	25	86	147
Sandhill Crane	23	56	112	191
Savannah Sparrow	46	67	250	363
Say’s Phoebe	30	91	174	295
Semipalmated Plover	2	9	1	12
Sharp-shinned Hawk	48	98	186	332
Sharp-tailed Grouse	0	0	1	1
Short-eared Owl	43	45	59	147
Snowy Egret	6	27	14	47
Snowy Plover	3	17	16	36
Solitary Sandpiper	3	3	0	6
Song Sparrow	24	22	363	409
Sooty Grouse	19	27	119	165
Sora	47	65	117	229
Spotted Owl	121	3	1	125
Spotted Sandpiper	49	56	283	388
Spotted Towhee	28	51	301	380
Spruce Grouse	3	2	6	11
Steller’s Jay	12	33	290	335
Swainson’s Hawk	24	93	130	247
Swainson’s Thrush	12	61	215	288
Townsend’s Solitaire	38	51	202	291
Townsend’s Warbler	22	97	124	243
Tree Swallow	19	55	316	390
Tricolored Blackbird	6	46	14	66
Trumpeter Swan	13	35	9	57
Tufted Puffin	2	8	14	24
Turkey Vulture	20	24	383	427
Upland Sandpiper	5	0	2	7
Varied Thrush	33	45	137	215
Vaux’s Swift	19	79	228	326
Veery	11	17	21	49
Vesper Sparrow	31	46	254	331
Violet-green Swallow	41	36	335	412
Virginia Rail	36	96	111	243
Virginia’s Warbler	5	2	0	7
Warbling Vireo	35	59	288	382
Western Bluebird	34	74	228	336
Western Grebe	10	72	70	152
Western Gull	1	0	25	26
Western Kingbird	29	66	261	356
Western Meadowlark	20	43	309	372
Western Screech-Owl	70	71	136	277
Western Tanager	17	51	320	388
Western Wood-Pewee	19	39	339	397
White-breasted Nuthatch	22	54	188	264
White-crowned Sparrow	26	120	210	356
White-faced Ibis	8	65	42	115
White-headed Woodpecker	25	33	90	148
White-tailed Kite	7	26	25	58
White-throated Swift	16	67	41	124
White-winged Crossbill	8	6	3	17
Wild Turkey	13	139	92	244
Willet	8	52	67	127
Williamson’s Sapsucker	15	26	122	163
Willow Flycatcher	43	97	196	336
Wilson’s Phalarope	46	68	107	221
Wilson’s Snipe	36	59	216	311
Wilson’s Warbler	31	74	233	338
Wood Duck	46	69	164	279
Wrentit	4	36	80	120
Yellow Rail	4	6	4	14
Yellow Warbler	30	57	302	389
Yellow-billed Cuckoo	1	6	0	7
Yellow-breasted Chat	28	102	153	283
Yellow-headed Blackbird	31	61	138	230
Yellow-rumped Warbler	20	41	288	349

Table 2

Average abundance index from Oregon BBS routes during the 5 BBA years compared to BBS routes during a more recent 5 year period.  Sorted from smallest to largest ratio, potentially suggesting the greatest to least declines.  Number and location of BBS routes varies somewhat annually with unknown influence on trends analysis.

Species	1995-1999 mean	2013-2017 mean	Change	Ratio
Black Tern	1.40	0.34	-1.06	0.24
Evening Grosbeak	2.20	0.69	-1.51	0.31
Pine Siskin	3.80	1.25	-2.54	0.33
Western Gull	17.80	6.92	-10.88	0.39
California Gull	2.79	1.12	-1.66	0.40
Glaucous-winged Gull	0.99	0.42	-0.57	0.42
Green Heron	0.13	0.06	-0.08	0.44
Cinnamon Teal	1.01	0.45	-0.57	0.44
Lesser Scaup	0.52	0.23	-0.28	0.45
Veery	0.05	0.02	-0.02	0.47
Spotted Owl	0.00	0.00	0.00	0.47
Forster’s Tern	1.66	0.79	-0.86	0.48
Black-crowned Night-Heron	0.23	0.11	-0.12	0.49
American Wigeon	0.29	0.14	-0.15	0.50
Northern Pintail	0.32	0.16	-0.16	0.50
Horned Lark	20.67	10.42	-10.25	0.50
Rufous Hummingbird	1.17	0.60	-0.57	0.51
Trumpeter Swan	0.08	0.04	-0.04	0.53
Golden-crowned Kinglet	3.04	1.65	-1.40	0.54
Pine Grosbeak	0.02	0.01	-0.01	0.55
American Bittern	0.15	0.08	-0.07	0.55
Vesper Sparrow	7.12	3.90	-3.22	0.55
Bushtit	1.43	0.80	-0.63	0.56
Red-eyed Vireo	0.06	0.04	-0.03	0.56
Marbled Murrelet	0.02	0.01	-0.01	0.57
Rock Wren	4.31	2.51	-1.80	0.58
Orange-crowned Warbler	2.98	1.74	-1.24	0.58
Cassin’s Finch	6.76	3.97	-2.79	0.59
Barn Swallow	5.34	3.15	-2.19	0.59
Ring-necked Pheasant	4.82	2.88	-1.94	0.60
White-crowned Sparrow	8.71	5.21	-3.50	0.60
Pinyon Jay	0.81	0.49	-0.33	0.60
House Finch	3.87	2.35	-1.52	0.61
Brown-headed Cowbird	7.44	4.54	-2.91	0.61
Savannah Sparrow	3.16	1.97	-1.20	0.62
Black-throated Gray Warbler	2.86	1.80	-1.06	0.63
American Coot	2.06	1.29	-0.76	0.63
Wilson’s Phalarope	0.60	0.39	-0.22	0.64
Yellow Warbler	2.45	1.58	-0.87	0.64
Redhead	1.72	1.12	-0.60	0.65
Chipping Sparrow	9.44	6.23	-3.21	0.66
Ruby-crowned Kinglet	1.52	1.01	-0.51	0.66
Northern Saw-whet Owl	0.00	0.00	0.00	0.67
Snowy Egret	0.05	0.03	-0.02	0.67
Brewer’s Blackbird	42.28	28.56	-13.72	0.68
Mountain Chickadee	12.08	8.22	-3.86	0.68
Gray Partridge	0.04	0.03	-0.01	0.69
Cedar Waxwing	1.76	1.22	-0.54	0.69
Lark Sparrow	1.49	1.04	-0.46	0.69
Brewer’s Sparrow	42.06	29.20	-12.86	0.69
Western Meadowlark	50.60	35.22	-15.39	0.70
Red-naped Sapsucker	0.17	0.12	-0.05	0.70
European Starling	19.82	13.88	-5.94	0.70
Violet-green Swallow	11.52	8.11	-3.42	0.70
Spotted Sandpiper	0.54	0.38	-0.16	0.71
American Robin	32.08	22.69	-9.40	0.71
Lewis’s Woodpecker	0.09	0.06	-0.03	0.71
Grasshopper Sparrow	0.07	0.05	-0.02	0.71
Sage Thrasher	42.80	30.99	-11.81	0.72
Olive-sided Flycatcher	2.67	1.94	-0.73	0.73
Bufflehead	0.16	0.12	-0.04	0.74
Ring-billed Gull	9.32	6.96	-2.36	0.75
Sora	0.19	0.14	-0.05	0.75
Red-winged Blackbird	13.70	10.28	-3.42	0.75
Song Sparrow	8.54	6.43	-2.11	0.75
Greater Sage-Grouse	0.26	0.20	-0.06	0.76
Killdeer	2.74	2.08	-0.66	0.76
Short-eared Owl	0.17	0.13	-0.04	0.76
Eared Grebe	1.82	1.40	-0.43	0.77
Northern Rough-winged Swallow	1.17	0.90	-0.27	0.77
MacGillivray’s Warbler	4.43	3.42	-1.01	0.77
American Goldfinch	2.97	2.30	-0.67	0.77
Williamson’s Sapsucker	0.69	0.54	-0.16	0.78
Belted Kingfisher	0.25	0.19	-0.05	0.79
Yellow-headed Blackbird	8.04	6.34	-1.70	0.79
Western Screech-Owl	0.01	0.01	0.00	0.79
Wilson’s Warbler	3.48	2.76	-0.73	0.79
Calliope Hummingbird	0.10	0.08	-0.02	0.79
Bullock’s Oriole	1.70	1.36	-0.34	0.80
Red-breasted Nuthatch	6.11	4.89	-1.22	0.80
Wilson’s Snipe	2.84	2.27	-0.57	0.80
Black-capped Chickadee	2.20	1.77	-0.43	0.80
American White Pelican	13.17	10.58	-2.59	0.80
Burrowing Owl	0.22	0.18	-0.04	0.81
Willet	1.73	1.41	-0.32	0.81
Great Horned Owl	0.19	0.15	-0.04	0.81
Dusky Flycatcher	7.25	5.94	-1.31	0.82
Hermit Thrush	7.66	6.31	-1.35	0.82
Pygmy Nuthatch	0.97	0.80	-0.16	0.83
Green-tailed Towhee	3.78	3.14	-0.64	0.83
Gadwall	1.18	0.98	-0.20	0.83
House Sparrow	5.27	4.39	-0.88	0.83
Red Crossbill	24.32	20.29	-4.04	0.83
Wrentit	5.08	4.24	-0.84	0.83
Clark’s Nutcracker	1.14	0.96	-0.18	0.85
California Quail	5.49	4.65	-0.85	0.85
Blue-winged Teal	0.05	0.04	-0.01	0.85
Caspian Tern	0.17	0.14	-0.03	0.85
Pacific Wren	3.90	3.32	-0.58	0.85
American Kestrel	1.26	1.08	-0.19	0.85
Chestnut-backed Chickadee	4.19	3.58	-0.61	0.85
Long-eared Owl	0.00	0.00	0.00	0.86
Varied Thrush	1.81	1.56	-0.24	0.86
Western Wood-Pewee	10.73	9.31	-1.42	0.87
Spotted Towhee	11.88	10.33	-1.55	0.87
Tree Swallow	3.03	2.64	-0.39	0.87
Vaux’s Swift	1.07	0.94	-0.13	0.88
Steller’s Jay	7.85	6.92	-0.93	0.88
American Avocet	1.29	1.14	-0.14	0.89
Virginia Rail	0.03	0.03	0.00	0.89
House Wren	2.91	2.59	-0.31	0.89
Marsh Wren	1.26	1.15	-0.11	0.91
Oak Titmouse	0.39	0.36	-0.03	0.91
Mountain Quail	0.97	0.89	-0.08	0.92
Bewick’s Wren	1.17	1.07	-0.09	0.92
Nashville Warbler	1.04	0.96	-0.08	0.92
Purple Finch	1.25	1.15	-0.09	0.92
Common Yellowthroat	1.14	1.06	-0.08	0.93
Downy Woodpecker	0.26	0.24	-0.02	0.93
White-throated Swift	0.67	0.63	-0.04	0.95
Common Nighthawk	3.13	2.98	-0.15	0.95
Swainson’s Thrush	14.71	14.01	-0.70	0.95
Western Kingbird	2.34	2.23	-0.11	0.95
Ruffed Grouse	0.07	0.06	0.00	0.95
Townsend’s Warbler	2.90	2.78	-0.12	0.96
Brown Creeper	0.86	0.83	-0.03	0.96
Mountain Bluebird	3.34	3.21	-0.13	0.96
Hermit Warbler	14.43	13.89	-0.54	0.96
Hairy Woodpecker	1.13	1.10	-0.03	0.97
Wood Duck	0.15	0.14	0.00	0.97
American Crow	6.72	6.62	-0.10	0.99
Chukar	3.08	3.07	-0.02	0.99
Cassin’s Vireo	1.34	1.34	0.00	1.00
Cliff Swallow	137.65	137.16	-0.50	1.00
Bank Swallow	4.22	4.26	0.03	1.01
Black-headed Grosbeak	9.75	9.89	0.13	1.01
Northern Goshawk	0.02	0.02	0.00	1.02
Hutton’s Vireo	1.35	1.37	0.02	1.02
Mourning Dove	6.14	6.24	0.11	1.02
American Dipper	0.05	0.05	0.00	1.02
Gray Jay	0.61	0.62	0.02	1.03
Warbling Vireo	4.49	4.65	0.16	1.03
Bobolink	0.11	0.11	0.00	1.04
Pied-billed Grebe	0.29	0.30	0.01	1.05
Green-winged Teal	0.09	0.10	0.00	1.05
Northern Harrier	0.45	0.47	0.02	1.05
Canvasback	0.22	0.23	0.01	1.05
California Towhee	0.17	0.18	0.01	1.06
Eastern Kingbird	0.18	0.19	0.01	1.07
Yellow-breasted Chat	0.79	0.84	0.06	1.08
Golden Eagle	0.32	0.34	0.03	1.08
Common Merganser	0.20	0.22	0.02	1.11
Lazuli Bunting	4.03	4.47	0.44	1.11
Band-tailed Pigeon	3.06	3.41	0.34	1.11
Black-throated Sparrow	0.52	0.58	0.07	1.13
Juniper Titmouse	0.02	0.02	0.00	1.14
Blue-gray Gnatcatcher	0.02	0.02	0.00	1.15
Say’s Phoebe	0.65	0.76	0.10	1.16
White-tailed Kite	0.00	0.00	0.00	1.16
Tricolored Blackbird	1926.64	2242.38	315.74	1.16
Fox Sparrow	0.72	0.83	0.12	1.17
Black-billed Magpie	7.56	8.88	1.32	1.17
Northern Shoveler	0.22	0.26	0.04	1.18
Western Tanager	17.12	20.30	3.19	1.19
Double-crested Cormorant	1.26	1.50	0.24	1.19
White-headed Woodpecker	0.20	0.24	0.04	1.20
Hammond’s Flycatcher	3.50	4.19	0.68	1.20
White-breasted Nuthatch	0.55	0.66	0.11	1.20
Sharp-shinned Hawk	0.02	0.03	0.00	1.20
Great Egret	0.84	1.01	0.18	1.21
Gray Flycatcher	7.61	9.51	1.90	1.25
Rock Pigeon	1.71	2.14	0.43	1.25
Canyon Wren	0.10	0.12	0.03	1.26
Swainson’s Hawk	0.27	0.34	0.07	1.26
Sandhill Crane	2.76	3.51	0.75	1.27
Common Poorwill	0.08	0.10	0.02	1.27
American Three-toed Woodpecker	0.02	0.03	0.01	1.27
Lincoln’s Sparrow	0.23	0.30	0.07	1.29
Western Bluebird	0.50	0.64	0.15	1.29
Northern Mockingbird	0.00	0.00	0.00	1.30
Northern Pygmy-Owl	0.04	0.06	0.01	1.32
Pileated Woodpecker	0.54	0.71	0.17	1.32
Ash-throated Flycatcher	0.92	1.26	0.34	1.37
Lesser Goldfinch	0.81	1.11	0.30	1.37
Ruddy Duck	0.36	0.50	0.14	1.38
Red-breasted Sapsucker	0.58	0.81	0.23	1.39
Black-chinned Hummingbird	0.02	0.02	0.01	1.44
Turkey Vulture	1.28	1.88	0.60	1.47
Common Raven	8.34	12.61	4.27	1.51
Pelagic Cormorant	0.18	0.28	0.10	1.53
Black-backed Woodpecker	0.18	0.28	0.10	1.55
Purple Martin	0.20	0.32	0.12	1.58
Townsend’s Solitaire	0.89	1.43	0.53	1.59
Dusky Grouse	0.04	0.06	0.02	1.61
Sooty Grouse	0.13	0.21	0.08	1.63
Loggerhead Shrike	0.85	1.40	0.55	1.64
Cooper’s Hawk	0.04	0.07	0.03	1.66
Long-billed Curlew	4.10	6.89	2.79	1.68
Ferruginous Hawk	0.14	0.24	0.10	1.69
Barn Owl	0.01	0.01	0.01	1.69
Franklin’s Gull	30.29	52.46	22.17	1.73
Prairie Falcon	0.22	0.38	0.16	1.74
Black Phoebe	0.08	0.15	0.07	1.80
Gray Catbird	0.03	0.06	0.03	1.82
Hooded Merganser	0.01	0.02	0.01	1.84
Acorn Woodpecker	2.04	3.83	1.79	1.88
Canada Goose	11.50	22.08	10.58	1.92
Black-necked Stilt	0.50	0.97	0.47	1.94
Barred Owl	0.01	0.03	0.01	2.01
Osprey	0.27	0.65	0.38	2.39
White-faced Ibis	141.69	424.36	282.68	3.00
Bald Eagle	0.06	0.22	0.15	3.55
Peregrine Falcon	0.01	0.03	0.02	3.70
Ring-necked Duck	0.16	0.59	0.43	3.72
Red-shouldered Hawk	0.02	0.12	0.09	5.16
Anna’s Hummingbird	0.03	0.16	0.13	5.60
Wild Turkey	0.07	0.53	0.46	7.75
Eurasian Collared-Dove	0.00	4.37	4.37	2064.81