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

Maps in Alphabetical Order

Maps in Phylogenetic Order

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