BirdAnalyst
Species · BCR 15 · BBS 2026 Release · 1966–2025

Yellow Warbler In Sierra Nevada

All regionsSierra NevadaForest birds

Yellow Warbler in Sierra Nevada has risen sharply: up 55% on the route-weighted index since 1971.

+55%Since 1971TrendPercent 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 →
36Routes 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 →

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 →

Yellow Warbler has risen sharply in Sierra Nevada: up 55% on the route-weighted index since 1971.

Yellow Warbler In Sierra Nevada Population Forecast

If the recent trend holds, Yellow Warbler in Sierra Nevada is projected to fall about 43% by 2030 — from 4.3 in 2025 to a central estimate of 2.5 (95% range 0.19–4.7). A 5-year backtest shows a typical error of ±43.4%, with 40% of held-out values landing inside the 95% band.

-43%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 →
2.5Projected 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 →
0.19–4.795% 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 →
±43.4%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, Yellow Warbler in Sierra Nevada is projected to fall about 43% by 2030 — from 4.3 in 2025 to a central estimate of 2.5 (95% range 0.19–4.7). A 5-year backtest shows a typical error of ±43.4%, with 40% 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 →
20262.60.324.9
20272.60.294.8
20282.50.254.8
20292.50.224.8
20302.50.194.7

Routes In Sierra Nevada

Routes recording Yellow Warbler in Sierra Nevada.
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 →
GeneseeCALIFORNIA292024
JohnsvilleCALIFORNIA182025
RivertonCALIFORNIA102025
Tahoe NfCALIFORNIA101994
PaxtonCALIFORNIA102025
ChilcootCALIFORNIA92024
WoodfordsCALIFORNIA82025
Silver CityCALIFORNIA82001
Bass LakeCALIFORNIA52011
Tuolumne GroveCALIFORNIA52025
Meadow ValleyCALIFORNIA52025
WestvilleCALIFORNIA42025
SattleyCALIFORNIA42025
DownievilleCALIFORNIA42025
LakeshoreCALIFORNIA42014
ChesterCALIFORNIA42016
Last ChanceCALIFORNIA42019
Lassen ParkCALIFORNIA31989
LumberyardCALIFORNIA32025
Kings CanyonCALIFORNIA32016
Little TruckeeCALIFORNIA32025
Greenhorn MtCALIFORNIA21985
Higgins CornCALIFORNIA22025
Eagle LakeCALIFORNIA12011
Cottage SpgsCALIFORNIA11974

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