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Species · BCR 10 · BBS 2026 Release · 1966–2025

Swainson's Thrush In Northern Rockies

All regionsNorthern RockiesForest birds

Swainson's Thrush in Northern Rockies has increased: up 45% on the route-weighted index since 1970.

+45%Since 1970TrendPercent 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 →
133Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

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

No notable trend signals for Swainson's Thrush in Northern Rockies. See the full index history below.

Swainson's Thrush In Northern Rockies Population Forecast

If the recent trend holds, Swainson's Thrush in Northern Rockies is projected to rise about 38% by 2030 — from 8.6 in 2025 to a central estimate of 12 (95% range 8.6–15). A 5-year backtest shows a typical error of ±19.6%, with 100% of held-out values landing inside the 95% band.

+38%Change by 2030TrendPercent 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 →
12Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
8.6–1595% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±19.6%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Swainson's Thrush in Northern Rockies is projected to rise about 38% by 2030 — from 8.6 in 2025 to a central estimate of 12 (95% range 8.6–15). A 5-year backtest shows a typical error of ±19.6%, with 100% of held-out values landing inside the 95% band.19682030
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
2026118.215
2027128.315
2028128.415
2029128.515
2030128.615

Routes In Northern Rockies

Routes recording Swainson's Thrush in Northern Rockies.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
Libby DamMONTANA1072025
Whitefish LakeMONTANA982024
Lolo PassIDAHO962019
Swan LakeMONTANA902025
Thompson RivMONTANA762024
AveryIDAHO712025
NoxonMONTANA612023
St RegisMONTANA572025
CusickWASHINGTON562025
Fish CreekMONTANA552024
PierceIDAHO532007
Eagle CreekOREGON472025
Sullivan Lake 2WASHINGTON462025
SkalkahoMONTANA451998
Deep CreekIDAHO441985
Greenoagh 3MONTANA442025
CoolinIDAHO432025
GrangevilleIDAHO422025
Marble CreekIDAHO422025
Twin LakesWASHINGTON422025
N Fork Cda RIDAHO362019
Sullivan LkWASHINGTON361999
WoodmanMONTANA352025
L Pend O NwrWASHINGTON352024
Baldy MountainIDAHO332016

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.