BirdAnalyst
Species · California · BBS 2025 Release · 1966–2024

Brown Pelican Population Trend in California

All statesWetland birds

Brown Pelican in California has surged: up 525% on the route-weighted index since 1974.

+525%Since 1974TrendPercent 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 →
14Routes 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 →
51YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Brown Pelican 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 →

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 →

Brown Pelican has surged in California: up 525% on the route-weighted index since 1974.

Brown Pelican Population Forecast in California

If the recent trend holds, Brown Pelican in California is projected to rise about 83% by 2029 — from 0.18 in 2024 to a central estimate of 0.33 (95% range 0.00–0.96). A 5-year backtest shows a typical error of ±77.4%, with 80% of held-out values landing inside the 95% band.

+83%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 →
0.33Projected 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 →
0.00–0.9695% 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 →
±77.4%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, Brown Pelican in California is projected to rise about 83% by 2029 — from 0.18 in 2024 to a central estimate of 0.33 (95% range 0.00–0.96). A 5-year backtest shows a typical error of ±77.4%, with 80% of held-out values landing inside the 95% band.19722029
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 →
20250.330.000.95
20260.330.000.95
20270.330.000.96
20280.330.000.96
20290.330.000.96

Brown Pelican Survey Routes in California

Routes recording Brown Pelican 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 →
S Catalina8520221988
Morro Bay6120181977
Bodega Bay3020211972
Brawley1520062006
Harbor Lake 21420242014
Honeydew520141975
Redwood N.P.420062006
Poway419801973
Niland320192007
Crescent Cty320021984
Fairfax320241978
Harbor Lake119901978
Fish Rock120121977
Laytonville119871983

Brown Pelican Population Trend in Other States

alabamafloridageorgialouisiananorth-carolinaoregonsouth-carolinatexasvirginiawashington

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