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

Great-tailed Grackle In Coastal California

All regionsCoastal CaliforniaWetland birds

Great-tailed Grackle in Coastal California has surged: up 14× on the route-weighted index since 2001.

14×Since 2001TrendPercent 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 →
37Routes 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 →
26YearsYears 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 Great-tailed Grackle in Coastal California. See the full index history below.

Great-tailed Grackle In Coastal California Population Forecast

If the recent trend holds, Great-tailed Grackle in Coastal California is projected to stay roughly flat through 2030, near 0.73 (95% range 0.27–1.2). A 5-year backtest shows a typical error of ±46.3%, with 100% of held-out values landing inside the 95% band.

-7%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 →
0.73Projected 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 →
0.27–1.295% 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 →
±46.3%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, Great-tailed Grackle in Coastal California is projected to stay roughly flat through 2030, near 0.73 (95% range 0.27–1.2). A 5-year backtest shows a typical error of ±46.3%, with 100% of held-out values landing inside the 95% band.19942030
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 →
20260.650.191.1
20270.670.211.1
20280.690.231.1
20290.710.251.2
20300.730.271.2

Routes In Coastal California

Routes recording Great-tailed Grackle 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 →
PenningtonCALIFORNIA122025
Buena VistaCALIFORNIA82019
OrlandCALIFORNIA72022
MorenoCALIFORNIA62025
Ora LomaCALIFORNIA62024
Jofegan 2CALIFORNIA62025
Orange CoveCALIFORNIA52012
AthloneCALIFORNIA52007
CrestonCALIFORNIA42021
LockwoodCALIFORNIA42025
Harbor Lake 2CALIFORNIA42024
SangerCALIFORNIA32023
Elizabeth LkCALIFORNIA32016
AtwaterCALIFORNIA32007
ZamoraCALIFORNIA32022
Anza 2CALIFORNIA32019
Hollister 2CALIFORNIA32018
Elsinore MtnCALIFORNIA22022
AnzaCALIFORNIA22004
ArvinCALIFORNIA22022
OrovilleCALIFORNIA22024
Cal Hot SpgsCALIFORNIA22019
Staten Is.CALIFORNIA22023
South LakeCALIFORNIA22006
Red BluffCALIFORNIA12023

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