BirdAnalyst
Species · BCR 32 · BBS 2025 Release · 1966–2024

American Avocet In Coastal California

All regionsCoastal CaliforniaShorebirds

American Avocet in Coastal California has collapsed: down 80% on the route-weighted index since 1972.

-80%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 →
31Routes 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 →
52YearsYears 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 declinecomputed 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 →

American Avocet has collapsed in Coastal California: down 79% on the route-weighted index since 1972.

Forecast

If the recent trend holds, American Avocet in Coastal California is projected to fall about 33% by 2029 — from 0.06 in 2024 to a central estimate of 0.04 (95% range 0.00–0.80). A 5-year backtest shows a typical error of ±265.8%, with 100% of held-out values landing inside the 95% band.

-33%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 →
0.04Projected 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 →
0.00–0.8095% 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 →
±265.8%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, American Avocet in Coastal California is projected to fall about 33% by 2029 — from 0.06 in 2024 to a central estimate of 0.04 (95% range 0.00–0.80). A 5-year backtest shows a typical error of ±265.8%, with 100% of held-out values landing inside the 95% band.19702029
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 →
20250.100.000.86
20260.090.000.84
20270.070.000.83
20280.060.000.81
20290.040.000.80

Routes In Coastal California

Routes recording American Avocet 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 →
OilfieldsCALIFORNIA361998
HollisterCALIFORNIA132007
Big BearCALIFORNIA91973
Carrizo PlnCALIFORNIA92023
HughsonCALIFORNIA72023
MorenoCALIFORNIA71986
CordovaCALIFORNIA41977
TranquillityCALIFORNIA42000
ZamoraCALIFORNIA41988
CollegevilleCALIFORNIA31985
Tres PinosCALIFORNIA32003
MaricopaCALIFORNIA31990
ArvinCALIFORNIA31996
PenningtonCALIFORNIA21989
OrlandCALIFORNIA22013
PowayCALIFORNIA21980
Mesa GrandeCALIFORNIA22006
GlennCALIFORNIA22015
AtwaterCALIFORNIA22007
WestleyCALIFORNIA22024
Mark WestCALIFORNIA22007
LivermoreCALIFORNIA21985
Tres Pinos 2CALIFORNIA22006
Buena VistaCALIFORNIA22019
RiovistaCALIFORNIA11974

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