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Species · BCR 10 · BBS 2025 Release · 1966–2024

Wilson's Warbler In Northern Rockies

All regionsNorthern RockiesForest birds

Wilson's Warbler in Northern Rockies has held roughly steady: down 2% on the route-weighted index since 1970.

-2%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 →
123Routes 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 →
56YearsYears 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 Wilson's Warbler in Northern Rockies. See the full index history below.

Wilson's Warbler In Northern Rockies Population Forecast

If the recent trend holds, Wilson's Warbler in Northern Rockies is projected to rise about 19% by 2029 — from 0.48 in 2024 to a central estimate of 0.57 (95% range 0.06–1.1). A 5-year backtest shows a typical error of ±22.8%, with 100% of held-out values landing inside the 95% band.

+19%Change by 2029TrendPercent 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 →
0.57Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.06–1.195% 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 →
±22.8%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, Wilson's Warbler in Northern Rockies is projected to rise about 19% by 2029 — from 0.48 in 2024 to a central estimate of 0.57 (95% range 0.06–1.1). A 5-year backtest shows a typical error of ±22.8%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20250.570.061.1
20260.570.061.1
20270.570.061.1
20280.570.061.1
20290.570.061.1

Routes In Northern Rockies

Routes recording Wilson's Warbler 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 →
AveryIDAHO152023
Lolo PassIDAHO122019
Crazy WomanWYOMING102024
Green RiverWYOMING101982
Soda LakeWYOMING92024
Marble CreekIDAHO82023
CusickWASHINGTON82024
Logan PassMONTANA62024
WalcottWYOMING61982
Libby DamMONTANA52013
ArleeMONTANA52023
SulaMONTANA52024
SkalkahoMONTANA51992
Swan LakeMONTANA52021
Colter Bay 2WYOMING52022
LogdellOREGON42024
Hells CanyonOREGON42022
Colter BayWYOMING41997
CrowheartWYOMING42005
Fiddler LkWYOMING42024
BeaverheadMONTANA31997
ClancyMONTANA32023
Summit PrOREGON31982
UnityOREGON32000
Eagle CreekOREGON32022

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