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

Lewis's Woodpecker In Coastal California

All regionsCoastal CaliforniaForest birds

Lewis's Woodpecker in Coastal California has fallen sharply: down 74% on the route-weighted index since 1972.

-74%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 →
18Routes 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 →

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 →

Lewis's Woodpecker has fallen sharply in Coastal California: down 74% on the route-weighted index since 1972.

Lewis's Woodpecker In Coastal California Population Forecast

If the recent trend holds, Lewis's Woodpecker in Coastal California is projected to stay roughly flat through 2018, near 0.00 (95% range 0.00–0.10). A 5-year backtest shows a typical error of ±188.5%, with 80% of held-out values landing inside the 95% band.

n/aChange by 2018TrendPercent 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 →
0.00Projected 2018 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.1095% 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 →
±188.5%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, Lewis's Woodpecker in Coastal California is projected to stay roughly flat through 2018, near 0.00 (95% range 0.00–0.10). A 5-year backtest shows a typical error of ±188.5%, with 80% of held-out values landing inside the 95% band.19682018
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 →
20140.010.000.11
20150.000.000.11
20160.000.000.10
20170.000.000.10
20180.000.000.10

Routes In Coastal California

Routes recording Lewis's Woodpecker 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 →
LockwoodCALIFORNIA41973
CoalingaCALIFORNIA31976
HollisterCALIFORNIA21992
ReddingCALIFORNIA21977
HughsonCALIFORNIA11981
Tres PinosCALIFORNIA11994
ParkfieldCALIFORNIA12013
CohassetCALIFORNIA11976
OnoCALIFORNIA12008
AdelaidaCALIFORNIA11977
Mt BaldyCALIFORNIA11997
CrestonCALIFORNIA11985
Gold HillCALIFORNIA12003
Yolla BollyCALIFORNIA11998
Bartlett SpsCALIFORNIA11977
CopperopolisCALIFORNIA12008
OnealsCALIFORNIA11993
LivermoreCALIFORNIA11976

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