BirdAnalyst
Species · BCR 9 · BBS 2025 Release · 1966–2024

American Dipper In Great Basin

All regionsGreat BasinGeneralists

American Dipper in Great Basin has declined: down 30% on the route-weighted index since 1972.

-30%Since 1972TrendPercent 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 →
33Routes 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 →
51YearsYears 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 American Dipper in Great Basin. See the full index history below.

American Dipper In Great Basin Population Forecast

If the recent trend holds, American Dipper in Great Basin is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.06). A 5-year backtest shows a typical error of ±211.6%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.02Projected 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 →
0.00–0.0695% 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 →
±211.6%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, American Dipper in Great Basin is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.06). A 5-year backtest shows a typical error of ±211.6%, with 100% of held-out values landing inside the 95% band.19692029
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 →
20250.030.000.06
20260.020.000.06
20270.020.000.06
20280.020.000.06
20290.020.000.06

Routes In Great Basin

Routes recording American Dipper in Great Basin.
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 →
Humboldt NfNEVADA22006
Camp ShermanOREGON21994
TwispWASHINGTON21998
RonaldWASHINGTON22024
LikelyCALIFORNIA11984
Deep SpringsCALIFORNIA11977
Iron GateCALIFORNIA11996
SquirrelIDAHO12002
Magic MtnIDAHO12014
HenryIDAHO11981
JarbidgeNEVADA12009
ImnahaOREGON11993
PaisleyOREGON12021
Mt HoodOREGON12015
AdrianOREGON11987
Wizard FallsOREGON12016
Bly 2OREGON12008
Badger CreekOREGON12019
Picture FlatOREGON12018
HyrumUTAH11979
Hardware RanchUTAH12018
NewhalemWASHINGTON12011
IndexWASHINGTON11971
RimrockWASHINGTON12014
KendallWASHINGTON12024

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