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

Pacific Wren In Coastal California

All regionsCoastal CaliforniaForest birds

Pacific Wren in Coastal California has surged: up 20× on the route-weighted index since 1976.

20×Since 1976TrendPercent 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 →
12Routes 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 →
50YearsYears 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 Pacific Wren in Coastal California. See the full index history below.

Pacific Wren In Coastal California Population Forecast

If the recent trend holds, Pacific Wren in Coastal California is projected to stay roughly flat through 2030, near 1.2 (95% range 0.57–1.9). A 5-year backtest shows a typical error of ±286.6%, with 40% of held-out values landing inside the 95% band.

-10%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 →
1.2Projected 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 →
0.57–1.995% 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 →
±286.6%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, Pacific Wren in Coastal California is projected to stay roughly flat through 2030, near 1.2 (95% range 0.57–1.9). A 5-year backtest shows a typical error of ±286.6%, with 40% of held-out values landing inside the 95% band.19722030
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 →
20261.10.491.8
20271.20.511.8
20281.20.531.8
20291.20.551.9
20301.20.571.9

Routes In Coastal California

Routes recording Pacific Wren 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 →
PescaderoCALIFORNIA292025
Waterman GapCALIFORNIA122025
Point ReyesCALIFORNIA112025
FairfaxCALIFORNIA22024
Mark WestCALIFORNIA22012
Orange CoveCALIFORNIA11977
TehamaCALIFORNIA12018
MoragaCALIFORNIA12011
Glen EllenCALIFORNIA11981
Glen Ellen 2CALIFORNIA12008
TomheadCALIFORNIA12008
Hough SpringsCALIFORNIA12007

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