BirdAnalyst
Species · California · BBS 2026 Release · 1966–2025

American Avocet Population Trend in California

All statesShorebirds

American Avocet in California has declined: down 29% on the route-weighted index since 1972.

-29%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 →
49Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
55YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable American Avocet Trends in CaliforniaNotable 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 American Avocet in California. See the full index history below.

American Avocet Population Forecast in California

If the recent trend holds, American Avocet in California is projected to rise about 89% by 2030 — from 0.58 in 2025 to a central estimate of 1.1 (95% range 0.00–3.6). A 5-year backtest shows a typical error of ±174.6%, with 100% of held-out values landing inside the 95% band.

+89%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 →
1.1Projected 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 →
0.00–3.695% 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 →
±174.6%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 California is projected to rise about 89% by 2030 — from 0.58 in 2025 to a central estimate of 1.1 (95% range 0.00–3.6). A 5-year backtest shows a typical error of ±174.6%, with 100% of held-out values landing inside the 95% band.19702030
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 →
20261.20.003.7
20271.10.003.7
20281.10.003.6
20291.10.003.6
20301.10.003.6

American Avocet Survey Routes in California

Routes recording American Avocet in 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 →
Oilfields3619981970
Benton2820251974
Hollister1320071991
Haiwee Res1220051976
Carrizo Pln920231978
Big Bear919731973
Cedarville820251974
Hughson720231983
Moreno719861986
Clear Lk Res720181972
Goumaz620101997
Niland620251973
Nubieber520141971
Cordova419771974
Crowder Flat420092009
Macdoel420191983
Tranquillity420001972
Zamora419881975
Arvin319961973
Collegeville319851985
Likely320251988
Tres Pinos320031995
Dorris320191972
Maricopa319901990
Pennington219891973

American Avocet Population Trend in Other States

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