BirdAnalyst
Species · BCR 9 · BBS 2026 Release · 1966–2025

Orange-crowned Warbler In Great Basin

All regionsGreat BasinForest birds

Orange-crowned Warbler in Great Basin has declined: down 27% on the route-weighted index since 1970.

-27%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 →
99Routes 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 Orange-crowned Warbler in Great Basin. See the full index history below.

Orange-crowned Warbler In Great Basin Population Forecast

If the recent trend holds, Orange-crowned Warbler in Great Basin is projected to rise about 40% by 2030 — from 0.23 in 2025 to a central estimate of 0.32 (95% range 0.11–0.53). A 5-year backtest shows a typical error of ±32.4%, with 100% of held-out values landing inside the 95% band.

+40%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 →
0.32Projected 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 →
0.11–0.5395% 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 →
±32.4%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, Orange-crowned Warbler in Great Basin is projected to rise about 40% by 2030 — from 0.23 in 2025 to a central estimate of 0.32 (95% range 0.11–0.53). A 5-year backtest shows a typical error of ±32.4%, 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 →
20260.310.100.52
20270.310.110.52
20280.320.110.52
20290.320.110.53
20300.320.110.53

Routes In Great Basin

Routes recording Orange-crowned Warbler 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 →
Magic MtnIDAHO92025
HyrumUTAH81978
IndexWASHINGTON71971
AustinNEVADA62018
Comins LakeNEVADA52014
PendletonOREGON42011
WinthropWASHINGTON41989
MacdoelCALIFORNIA32019
Fall River MillsCALIFORNIA32010
SquirrelIDAHO32025
Ruby ValleyNEVADA31999
Humboldt Nf 2NEVADA32025
Oak CityUTAH32010
ArdenvoirWASHINGTON31984
PomeroyWASHINGTON32024
WaitsburgWASHINGTON31996
Medicine Mtn.CALIFORNIA22021
GiffordIDAHO22017
AlmoIDAHO22025
Daniels ResIDAHO21990
JarbidgeNEVADA22014
Humboldt NfNEVADA22018
Mt HoodOREGON22025
Lapham Res.OREGON22025
SistersOREGON22022

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