BirdAnalyst
Bird Conservation Region 10

Northern Rockies

An ecological region spanning Colorado, Idaho, Montana, Oregon, Utah, Washington, Wyoming, with 229 survey routes. BCRs are the natural unit for bird trends.

What Is Moving HereNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Brown Thrasher has collapsed in Northern Rockies: down 93% on the route-weighted index since 1970.

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Canada Goose has surged in Northern Rockies: up 34× on the route-weighted index since 1970.

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Evening Grosbeak has collapsed in Northern Rockies: down 93% on the route-weighted index since 1970.

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Eurasian Collared-Dove has surged in Northern Rockies: up 21× on the route-weighted index since 2007.

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Black-billed Cuckoo has collapsed in Northern Rockies: down 92% on the route-weighted index since 1972.

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Ring-billed Gull has surged in Northern Rockies: up 894% on the route-weighted index since 1971.

How Guilds Are FaringGuild trendA mean-index aggregate across the species in this group — the structural direction of the guild, with individual-species noise smoothed out.Full methodology →

-80%

Game birds

11 species
-50%

Shorebirds

10 species
-30%

Generalists

13 species
-27%

Wetland birds

27 species
-23%

Forest birds

87 species
-19%

Aerial insectivores

23 species
-16%

Grassland birds

16 species
+8%

Birds of prey

23 species
+130%

Arid-land birds

3 species
+203%

Waterfowl

22 species

Survey Routes

Species By FamilyTrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →

Hawks, Eagles & Kites Accipitridae

American Goshawk -69%Bald Eagle +853%Cooper's Hawk -13%Ferruginous Hawk +213%Golden Eagle +209%Northern Harrier +2%Red-tailed Hawk +212%Sharp-shinned Hawk -47%Swainson's Hawk +424%

Bushtits Aegithalidae

Bushtit -70%

Larks Alaudidae

Horned Lark -31%

Kingfishers Alcedinidae

Belted Kingfisher -51%

Ducks, Geese & Waterfowl Anatidae

American Wigeon -46%Barrow's Goldeneye +13%Blue-winged Teal -42%Bufflehead +223%Canada Goose 34×Canvasback +74%Cinnamon Teal -41%Common Goldeneye -72%Common Merganser +99%Gadwall +463%Green-winged Teal -18%Harlequin Duck -38%Hooded Merganser -39%Lesser Scaup +82%Mallard +51%Northern Pintail -17%Northern Shoveler -33%Redhead +147%Ring-necked Duck +78%Ruddy Duck +278%Trumpeter Swan -84%Wood Duck +144%

Swifts Apodidae

Black Swift -73%Vaux's Swift -49%White-throated Swift +256%

Herons, Egrets & Bitterns Ardeidae

American Bittern -40%Black-crowned Night Heron -58%Great Blue Heron -24%Snowy Egret +24%

Waxwings Bombycillidae

Cedar Waxwing +491%

Longspurs & Snow Buntings Calcariidae

Chestnut-collared Longspur -87%Thick-billed Longspur +1%

Nightjars & Nighthawks Caprimulgidae

Common Nighthawk +127%Common Poorwill +28%

Cardinals & Grosbeaks Cardinalidae

Black-headed Grosbeak +350%Blue Grosbeak +333%Lazuli Bunting +60%Western Tanager +108%

New World Vultures Cathartidae

Turkey Vulture +341%

Treecreepers Certhiidae

Brown Creeper +13%

Plovers & Lapwings Charadriidae

Killdeer -55%Mountain Plover -82%

Dippers Cinclidae

American Dipper +54%

Pigeons & Doves Columbidae

Eurasian Collared-Dove 21×Mourning Dove -39%Rock Pigeon +11%

Crows, Jays & Magpies Corvidae

American Crow -42%Black-billed Magpie -33%Canada Jay -31%Clark's Nutcracker +9%Common Raven +121%Pinyon Jay +38%Steller's Jay -52%Woodhouse's Scrub-Jay +247%

Cuckoos, Roadrunners & Anis Cuculidae

Black-billed Cuckoo -92%

Falcons & Caracaras Falconidae

American Kestrel -22%Merlin -56%Peregrine Falcon +63%Prairie Falcon +146%

Finches Fringillidae

American Goldfinch -19%Cassin's Finch -4%Evening Grosbeak -93%House Finch +312%Lesser Goldfinch +395%Pine Grosbeak -50%Pine Siskin -26%Purple Finch -79%Red Crossbill +94%White-winged Crossbill -75%

Loons Gaviidae

Common Loon -23%

Cranes Gruidae

Sandhill Crane +550%

Swallows & Martins Hirundinidae

Bank Swallow -80%Barn Swallow -51%Cliff Swallow +8%Northern Rough-winged Swallow +17%Purple Martin -44%Tree Swallow +32%Violet-green Swallow +9%

Blackbirds & Orioles Icteridae

Bobolink +134%Brewer's Blackbird -62%Brown-headed Cowbird +42%Bullock's Oriole +21%Common Grackle -66%Red-winged Blackbird -8%Western Meadowlark -24%Yellow-headed Blackbird -17%

Yellow-breasted Chat Icteriidae

Yellow-breasted Chat +83%

Shrikes Laniidae

Loggerhead Shrike +42%

Gulls, Terns & Skimmers Laridae

Black Tern -78%California Gull +71%Caspian Tern -27%Forster's Tern -55%Franklin's Gull +279%Ring-billed Gull +894%

Mockingbirds & Thrashers Mimidae

Brown Thrasher -93%Gray Catbird -15%Northern Mockingbird -57%Sage Thrasher +114%

Wagtails & Pipits Motacillidae

American Pipit -77%Sprague's Pipit -91%

New World Quail Odontophoridae

California Quail +91%Mountain Quail +3%

Osprey Pandionidae

Osprey +53%

Chickadees & Titmice Paridae

Black-capped Chickadee -35%Chestnut-backed Chickadee +393%Juniper Titmouse -90%Mountain Chickadee +19%

Wood-Warblers Parulidae

American Redstart -45%Black-throated Gray Warbler -25%Common Yellowthroat -21%MacGillivray's Warbler +55%Nashville Warbler +290%Northern Waterthrush +433%Orange-crowned Warbler +190%Ovenbird +6%Tennessee Warbler +20%Townsend's Warbler +219%Wilson's Warbler -2%Yellow Warbler +19%

New World Sparrows Passerellidae

Baird's Sparrow -67%Brewer's Sparrow +140%Chipping Sparrow -25%Clay-colored Sparrow +178%Field Sparrow -36%Fox Sparrow +43%Grasshopper Sparrow +142%Green-tailed Towhee +72%Lark Bunting -34%Lark Sparrow +61%Lincoln's Sparrow +220%Sagebrush Sparrow +120%Savannah Sparrow +132%Song Sparrow +23%Spotted Towhee -36%Vesper Sparrow +61%White-crowned Sparrow +12%

Old World Sparrows Passeridae

House Sparrow +51%

Pelicans Pelecanidae

American White Pelican -61%

Cormorants Phalacrocoracidae

Double-crested Cormorant -5%

Pheasants, Grouse & Turkeys Phasianidae

Chukar +24%Dusky Grouse +27%Gray Partridge +59%Greater Sage-Grouse -78%Ring-necked Pheasant -76%Ruffed Grouse +141%Sharp-tailed Grouse -63%Spruce Grouse -54%Wild Turkey +440%

Woodpeckers Picidae

American Three-toed Woodpecker +9%Black-backed Woodpecker -4%Downy Woodpecker -35%Hairy Woodpecker +33%Lewis's Woodpecker -78%Pileated Woodpecker +319%Red-naped Sapsucker +202%White-headed Woodpecker +27%Williamson's Sapsucker +376%

Grebes Podicipedidae

Clark's Grebe -59%Eared Grebe +207%Pied-billed Grebe -39%Red-necked Grebe -86%Western Grebe -82%

Gnatcatchers Polioptilidae

Blue-gray Gnatcatcher +129%

Rails, Gallinules & Coots Rallidae

American Coot +211%Sora -62%Virginia Rail -56%

Avocets & Stilts Recurvirostridae

American Avocet +18%Black-necked Stilt +104%

Kinglets Regulidae

Golden-crowned Kinglet +693%Ruby-crowned Kinglet +33%

Sandpipers & Allies Scolopacidae

Long-billed Curlew +76%Marbled Godwit +37%Spotted Sandpiper -29%Upland Sandpiper -81%Willet +32%Wilson's Phalarope +29%Wilson's Snipe -24%

Nuthatches Sittidae

Pygmy Nuthatch -53%Red-breasted Nuthatch +133%White-breasted Nuthatch -72%

Owls Strigidae

Barred Owl -48%Burrowing Owl -64%Great Gray Owl -68%Great Horned Owl -72%Northern Pygmy-Owl -51%Northern Saw-whet Owl -30%Short-eared Owl -43%Western Screech-Owl -77%

Starlings & Mynas Sturnidae

European Starling +52%

Ibises & Spoonbills Threskiornithidae

White-faced Ibis +67%

Hummingbirds Trochilidae

Black-chinned Hummingbird +55%Broad-tailed Hummingbird +544%Calliope Hummingbird -9%Rufous Hummingbird +48%

Wrens Troglodytidae

Bewick's Wren -39%Canyon Wren -57%Marsh Wren +145%Northern House Wren +116%Pacific Wren +606%Rock Wren +148%

Thrushes Turdidae

American Robin -50%Hermit Thrush +238%Mountain Bluebird -7%Swainson's Thrush +49%Townsend's Solitaire +1%Varied Thrush -16%Veery -70%Western Bluebird -29%

Tyrant Flycatchers Tyrannidae

Ash-throated Flycatcher +324%Dusky Flycatcher +180%Eastern Kingbird +15%Gray Flycatcher -33%Hammond's Flycatcher +230%Least Flycatcher +590%Olive-sided Flycatcher -13%Say's Phoebe +220%Western Kingbird +238%Western Wood-Pewee +37%Willow Flycatcher -41%

Vireos Vireonidae

Cassin's Vireo -21%Plumbeous Vireo -87%Red-eyed Vireo -47%Warbling Vireo +85%

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.