BirdAnalyst
Species · BCR 15 · BBS 2025 Release · 1966–2024

Hutton's Vireo In Sierra Nevada

All regionsSierra NevadaForest birds

Hutton's Vireo in Sierra Nevada has risen sharply: up 62% on the route-weighted index since 1972.

+62%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 →
25Routes 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 →

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 →

Hutton's Vireo has risen sharply in Sierra Nevada: up 62% on the route-weighted index since 1972.

Hutton's Vireo In Sierra Nevada Population Forecast

If the recent trend holds, Hutton's Vireo in Sierra Nevada is projected to rise about 965% by 2029 — from 0.21 in 2024 to a central estimate of 2.2 (95% range 0.72–3.8). A 5-year backtest shows a typical error of ±374.1%, with 40% of held-out values landing inside the 95% band.

+965%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 →
2.2Projected 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 →
0.72–3.895% 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 →
±374.1%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, Hutton's Vireo in Sierra Nevada is projected to rise about 965% by 2029 — from 0.21 in 2024 to a central estimate of 2.2 (95% range 0.72–3.8). A 5-year backtest shows a typical error of ±374.1%, with 40% 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 →
20252.10.583.6
20262.10.623.7
20272.20.653.7
20282.20.693.7
20292.20.723.8

Routes In Sierra Nevada

Routes recording Hutton's Vireo 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 →
CoultervilleCALIFORNIA92019
Forest HillCALIFORNIA82022
Silver CityCALIFORNIA72013
Forest Hill 2CALIFORNIA62005
Eagle LakeCALIFORNIA22022
WestvilleCALIFORNIA22022
Kings CanyonCALIFORNIA22013
Tuolumne GroveCALIFORNIA22023
Hat CreekCALIFORNIA22014
Meadow ValleyCALIFORNIA22019
Cottage SpgsCALIFORNIA11971
Bass LakeCALIFORNIA12019
LumberyardCALIFORNIA12019
SattleyCALIFORNIA12017
Butte MeadowCALIFORNIA12013
Higgins CornCALIFORNIA12024
DownievilleCALIFORNIA12024
RivertonCALIFORNIA12019
LakeshoreCALIFORNIA12000
Tahoe NfCALIFORNIA11993
PaxtonCALIFORNIA12022
Pollock PinesCALIFORNIA12022
PlacervilleCALIFORNIA12024
WawonaCALIFORNIA12024
StrawberryCALIFORNIA12019

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