BirdAnalyst
Bird Conservation Region 15

Sierra Nevada

An ecological region spanning California, with 40 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 →

California Gull has collapsed in Sierra Nevada: down 98% on the route-weighted index since 1974.

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 →

Common Raven has surged in Sierra Nevada: up 29× on the route-weighted index since 1973.

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 →

Yellow-headed Blackbird has collapsed in Sierra Nevada: down 97% on the route-weighted index since 1973.

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 →

Lazuli Bunting has surged in Sierra Nevada: up 12× on the route-weighted index since 1973.

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 →

American Goldfinch has collapsed in Sierra Nevada: down 97% 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 Sierra Nevada: up 671% on the route-weighted index since 1975.

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 →

-82%

Shorebirds

5 species
-69%

Birds of prey

14 species
-68%

Arid-land birds

6 species
-62%

Aerial insectivores

19 species
-59%

Generalists

12 species
-40%

Grassland birds

5 species
-40%

Forest birds

74 species
-37%

Game birds

4 species
+96%

Wetland birds

12 species
+327%

Waterfowl

6 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 -38%Bald Eagle +126%Cooper's Hawk -48%Golden Eagle -56%Northern Harrier +10%Red-shouldered Hawk +81%Red-tailed Hawk -34%Sharp-shinned Hawk -3%

Bushtits Aegithalidae

Bushtit -71%

Larks Alaudidae

Horned Lark -81%

Kingfishers Alcedinidae

Belted Kingfisher -56%

Ducks, Geese & Waterfowl Anatidae

Canada Goose +671%Common Merganser +84%Gadwall -5%Mallard +101%Northern Pintail -80%Wood Duck -74%

Swifts Apodidae

Black Swift -86%Vaux's Swift -65%White-throated Swift -64%

Herons, Egrets & Bitterns Ardeidae

Great Blue Heron -15%

Nightjars & Nighthawks Caprimulgidae

Common Nighthawk +142%Common Poorwill +96%

Cardinals & Grosbeaks Cardinalidae

Black-headed Grosbeak +16%Lazuli Bunting 12×Western Tanager +5%

New World Vultures Cathartidae

Turkey Vulture -19%

Treecreepers Certhiidae

Brown Creeper +137%

Plovers & Lapwings Charadriidae

Killdeer -88%

Dippers Cinclidae

American Dipper -58%

Pigeons & Doves Columbidae

Band-tailed Pigeon -58%Eurasian Collared-Dove +258%Mourning Dove -9%Rock Pigeon -23%

Crows, Jays & Magpies Corvidae

American Crow +88%Black-billed Magpie -50%California Scrub-Jay -80%Clark's Nutcracker -11%Common Raven 29×Pinyon Jay +7%Steller's Jay -21%

Falcons & Caracaras Falconidae

American Kestrel -58%

Finches Fringillidae

American Goldfinch -97%Cassin's Finch +41%Evening Grosbeak -64%House Finch -71%Lawrence's Goldfinch -94%Lesser Goldfinch -12%Pine Grosbeak -51%Pine Siskin -82%Purple Finch -70%Red Crossbill -9%

Cranes Gruidae

Sandhill Crane -48%

Swallows & Martins Hirundinidae

Barn Swallow -76%Cliff Swallow -1%Northern Rough-winged Swallow -75%Tree Swallow +94%Violet-green Swallow -81%

Blackbirds & Orioles Icteridae

Brewer's Blackbird -55%Brown-headed Cowbird -30%Bullock's Oriole -71%Red-winged Blackbird +322%Western Meadowlark +101%Yellow-headed Blackbird -98%

Yellow-breasted Chat Icteriidae

Yellow-breasted Chat +137%

Gulls, Terns & Skimmers Laridae

California Gull -98%Ring-billed Gull +202%

Mockingbirds & Thrashers Mimidae

California Thrasher -88%Northern Mockingbird +11%Sage Thrasher +164%

New World Quail Odontophoridae

California Quail -47%Mountain Quail +85%

Osprey Pandionidae

Osprey +48%

Chickadees & Titmice Paridae

Chestnut-backed Chickadee +272%Mountain Chickadee +74%Oak Titmouse -58%

Wood-Warblers Parulidae

Black-throated Gray Warbler +311%Hermit Warbler +109%MacGillivray's Warbler -8%Nashville Warbler +62%Orange-crowned Warbler -5%Wilson's Warbler -55%Yellow Warbler +37%

New World Sparrows Passerellidae

Brewer's Sparrow -55%California Towhee -6%Chipping Sparrow -30%Fox Sparrow +191%Green-tailed Towhee +43%Lark Sparrow -76%Lincoln's Sparrow -71%Rufous-crowned Sparrow +32%Savannah Sparrow -12%Song Sparrow +22%Spotted Towhee +91%Vesper Sparrow +2%White-crowned Sparrow -86%

Old World Sparrows Passeridae

House Sparrow +5%

Pelicans Pelecanidae

American White Pelican -40%

Pheasants, Grouse & Turkeys Phasianidae

Sooty Grouse +31%Wild Turkey +266%

Woodpeckers Picidae

Acorn Woodpecker -68%Black-backed Woodpecker +142%Downy Woodpecker -5%Hairy Woodpecker +83%Lewis's Woodpecker -86%Nuttall's Woodpecker -80%Pileated Woodpecker +251%Red-breasted Sapsucker +52%White-headed Woodpecker -13%Williamson's Sapsucker +35%

Grebes Podicipedidae

Pied-billed Grebe -65%Western Grebe +7%

Gnatcatchers Polioptilidae

Blue-gray Gnatcatcher +5%

Silky-flycatchers Ptiliogonatidae

Phainopepla -38%

Rails, Gallinules & Coots Rallidae

American Coot -63%

Kinglets Regulidae

Golden-crowned Kinglet -9%Ruby-crowned Kinglet -84%

Sandpipers & Allies Scolopacidae

Spotted Sandpiper -14%Willet -91%Wilson's Phalarope -52%Wilson's Snipe -76%

Nuthatches Sittidae

Pygmy Nuthatch -72%Red-breasted Nuthatch +61%White-breasted Nuthatch -62%

Owls Strigidae

Great Horned Owl -44%Northern Pygmy-Owl -74%Spotted Owl -82%

Starlings & Mynas Sturnidae

European Starling +4%

Sylviid Warblers Sylviidae

Wrentit -53%

Hummingbirds Trochilidae

Anna's Hummingbird +30%Black-chinned Hummingbird -52%Calliope Hummingbird -11%Rufous Hummingbird -61%

Wrens Troglodytidae

Bewick's Wren -72%Canyon Wren -46%Northern House Wren -38%Pacific Wren +266%Rock Wren +82%

Thrushes Turdidae

American Robin -62%Hermit Thrush -50%Mountain Bluebird -72%Swainson's Thrush +90%Townsend's Solitaire -14%Western Bluebird +40%

Tyrant Flycatchers Tyrannidae

Ash-throated Flycatcher -76%Black Phoebe +64%Dusky Flycatcher +32%Gray Flycatcher +568%Hammond's Flycatcher -25%Olive-sided Flycatcher -80%Western Kingbird +27%Western Wood-Pewee -34%Willow Flycatcher -86%

Vireos Vireonidae

Cassin's Vireo +21%Hutton's Vireo +62%Plumbeous Vireo -91%Warbling Vireo +97%

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