BirdAnalyst
Species · BCR 32 · BBS 2026 Release · 1966–2025

Lazuli Bunting In Coastal California

All regionsCoastal CaliforniaForest birds

Lazuli Bunting in Coastal California has surged: up 122% on the route-weighted index since 1970.

+122%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 →
98Routes 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 →

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 Coastal California: up 122% on the route-weighted index since 1970.

Lazuli Bunting In Coastal California Population Forecast

If the recent trend holds, Lazuli Bunting in Coastal California is projected to fall about 12% by 2030 — from 2.2 in 2025 to a central estimate of 1.9 (95% range 0.67–3.1). A 5-year backtest shows a typical error of ±110.2%, with 80% of held-out values landing inside the 95% band.

-12%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 →
1.9Projected 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 →
0.67–3.195% 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 →
±110.2%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 Coastal California is projected to fall about 12% by 2030 — from 2.2 in 2025 to a central estimate of 1.9 (95% range 0.67–3.1). A 5-year backtest shows a typical error of ±110.2%, with 80% 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 →
20261.90.653.1
20271.90.653.1
20281.90.663.1
20291.90.663.1
20301.90.673.1

Routes In Coastal California

Routes recording Lazuli Bunting in Coastal California.
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 →
CohassetCALIFORNIA392025
AnzaCALIFORNIA161995
PowayCALIFORNIA101980
OnoCALIFORNIA102011
Lake SuccessCALIFORNIA81996
JacksonCALIFORNIA81986
Elsinore MtnCALIFORNIA72025
Mt BaldyCALIFORNIA72024
ReddingCALIFORNIA71983
Green ValleyCALIFORNIA62023
Waterman GapCALIFORNIA62025
Yokohl ValCALIFORNIA51997
Foster ParkCALIFORNIA51994
Harbor LakeCALIFORNIA51975
El ToroCALIFORNIA51986
FallsvaleCALIFORNIA51981
SangerCALIFORNIA52024
Yolla BollyCALIFORNIA52025
Anza 2CALIFORNIA52025
FolsomCALIFORNIA42025
Lockwood ValCALIFORNIA42019
Mt LagunaCALIFORNIA41987
Lake CachumaCALIFORNIA42016
GreenfieldCALIFORNIA42023
Cal Hot SpgsCALIFORNIA42019

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