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

Lazuli Bunting In Sierra Nevada

All regionsSierra NevadaForest birds

Lazuli Bunting in Sierra Nevada has surged: up 15× on the route-weighted index since 1973.

15×Since 1973TrendPercent 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 →
35Routes 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 →
54YearsYears 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 →

Lazuli Bunting has surged in Sierra Nevada: up 15× on the route-weighted index since 1973.

Lazuli Bunting In Sierra Nevada Population Forecast

If the recent trend holds, Lazuli Bunting in Sierra Nevada is projected to fall about 43% by 2030 — from 10 in 2025 to a central estimate of 5.9 (95% range 3.2–8.5). A 5-year backtest shows a typical error of ±43%, with 20% 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 →
5.9Projected 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 →
3.2–8.595% 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%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, Lazuli Bunting in Sierra Nevada is projected to fall about 43% by 2030 — from 10 in 2025 to a central estimate of 5.9 (95% range 3.2–8.5). A 5-year backtest shows a typical error of ±43%, with 20% of held-out values landing inside the 95% band.19712030
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 →
20265.42.88.1
20275.52.98.2
20285.63.08.3
20295.83.18.4
20305.93.28.5

Routes In Sierra Nevada

Routes recording Lazuli Bunting 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 →
Pollock PinesCALIFORNIA582025
Forest HillCALIFORNIA432025
LakeshoreCALIFORNIA322024
PaxtonCALIFORNIA272025
Tuolumne GroveCALIFORNIA172025
GeneseeCALIFORNIA142024
Kings CanyonCALIFORNIA132024
KernvilleCALIFORNIA132008
Pine MountainCALIFORNIA92017
Eagle LakeCALIFORNIA72025
WestvilleCALIFORNIA72025
Hat CreekCALIFORNIA62018
Bass LakeCALIFORNIA52019
RivertonCALIFORNIA52025
PlacervilleCALIFORNIA52025
StrawberryCALIFORNIA52019
DownievilleCALIFORNIA32025
Meadow ValleyCALIFORNIA32025
Little TruckeeCALIFORNIA32025
WawonaCALIFORNIA32025
DardanelleCALIFORNIA22015
JohnsvilleCALIFORNIA22022
WoodfordsCALIFORNIA22025
LumberyardCALIFORNIA22025
Silver CityCALIFORNIA22013

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