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

Northern House Wren In Coastal California

All regionsCoastal CaliforniaForest birds

Northern House Wren in Coastal California has increased: up 32% on the route-weighted index since 1970.

+32%Since 1970TrendPercent 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 →
107Routes 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 →
57YearsYears 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 Northern House Wren in Coastal California. See the full index history below.

Northern House Wren In Coastal California Population Forecast

If the recent trend holds, Northern House Wren in Coastal California is projected to rise about 45% by 2030 — from 3.6 in 2025 to a central estimate of 5.2 (95% range 1.8–8.6). A 5-year backtest shows a typical error of ±47.2%, with 100% of held-out values landing inside the 95% band.

+45%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 →
5.2Projected 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 →
1.8–8.695% 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 →
±47.2%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, Northern House Wren in Coastal California is projected to rise about 45% by 2030 — from 3.6 in 2025 to a central estimate of 5.2 (95% range 1.8–8.6). A 5-year backtest shows a typical error of ±47.2%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20265.21.88.6
20275.21.88.6
20285.21.88.6
20295.21.88.6
20305.21.88.6

Routes In Coastal California

Routes recording Northern House 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 →
White RiverCALIFORNIA801992
Cal Hot SpgsCALIFORNIA672019
El ToroCALIFORNIA321999
Yokohl ValCALIFORNIA291997
Carmel ValCALIFORNIA292025
Santa YnezCALIFORNIA282019
Lake SuccessCALIFORNIA281996
JacksonCALIFORNIA211992
PowayCALIFORNIA201980
FallsvaleCALIFORNIA181981
Cleveland NfCALIFORNIA172018
Harbor Lake 2CALIFORNIA172024
Mesa GrandeCALIFORNIA162025
Cp. PendletonCALIFORNIA152003
Jofegan 2CALIFORNIA142025
Foster ParkCALIFORNIA131994
Mt BaldyCALIFORNIA132024
Lake HemetCALIFORNIA101986
Lake BerryessaCALIFORNIA102025
Bartlett SpsCALIFORNIA102018
South LakeCALIFORNIA102006
Cleveland Nf 2CALIFORNIA92022
Green ValleyCALIFORNIA82019
Lake CachumaCALIFORNIA82016
StonyfordCALIFORNIA82018

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