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

Northern Mockingbird In Coastal California

All regionsCoastal CaliforniaGeneralists

Northern Mockingbird in Coastal California has risen sharply: up 54% on the route-weighted index since 1970.

+54%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 →

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 →

Northern Mockingbird has risen sharply in Coastal California: up 54% on the route-weighted index since 1970.

Northern Mockingbird In Coastal California Population Forecast

If the recent trend holds, Northern Mockingbird in Coastal California is projected to fall about 35% by 2030 — from 15 in 2025 to a central estimate of 9.5 (95% range 5.0–14). A 5-year backtest shows a typical error of ±27.1%, with 80% of held-out values landing inside the 95% band.

-35%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 →
9.5Projected 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 →
5.0–1495% 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 →
±27.1%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 Mockingbird in Coastal California is projected to fall about 35% by 2030 — from 15 in 2025 to a central estimate of 9.5 (95% range 5.0–14). A 5-year backtest shows a typical error of ±27.1%, with 80% 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 →
20269.44.914
20279.54.914
20289.54.914
20299.54.914
20309.55.014

Routes In Coastal California

Routes recording Northern Mockingbird 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 →
Harbor LakeCALIFORNIA1241991
S CatalinaCALIFORNIA1212025
AuburnCALIFORNIA501980
MorenoCALIFORNIA422025
ParkfieldCALIFORNIA412025
GravesboroCALIFORNIA381995
Harbor Lake 2CALIFORNIA342024
HughsonCALIFORNIA322025
OrovilleCALIFORNIA302025
Hollister 2CALIFORNIA292024
CollegevilleCALIFORNIA282004
Staten Is.CALIFORNIA262025
Tres Pinos 2CALIFORNIA252011
TranquillityCALIFORNIA242024
ColmaCALIFORNIA231972
San YsidroCALIFORNIA222019
WestleyCALIFORNIA222025
Mark WestCALIFORNIA212025
Oak GroveCALIFORNIA202025
PowayCALIFORNIA201980
ZamoraCALIFORNIA202025
Ora LomaCALIFORNIA202025
Collegeville 2CALIFORNIA202023
RiovistaCALIFORNIA192025
South LakeCALIFORNIA192006

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