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

Western Meadowlark In Coastal California

All regionsCoastal CaliforniaGrassland birds

Western Meadowlark in Coastal California has collapsed: down 77% on the route-weighted index since 1970.

-77%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 →
110Routes 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 →
56YearsYears 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 →

Western Meadowlark has collapsed in Coastal California: down 77% on the route-weighted index since 1970.

Western Meadowlark In Coastal California Population Forecast

If the recent trend holds, Western Meadowlark in Coastal California is projected to fall about 25% by 2029 — from 11 in 2024 to a central estimate of 8.4 (95% range 0.00–21). A 5-year backtest shows a typical error of ±37.6%, with 100% of held-out values landing inside the 95% band.

-25%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 →
8.4Projected 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 →
0.00–2195% 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 →
±37.6%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, Western Meadowlark in Coastal California is projected to fall about 25% by 2029 — from 11 in 2024 to a central estimate of 8.4 (95% range 0.00–21). A 5-year backtest shows a typical error of ±37.6%, with 100% of held-out values landing inside the 95% band.19682029
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 →
2025110.0024
2026100.0023
20279.80.0022
20289.10.0022
20298.40.0021

Routes In Coastal California

Routes recording Western Meadowlark 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 →
AtwaterCALIFORNIA1222012
Carrizo PlnCALIFORNIA992023
RiovistaCALIFORNIA862024
VentucopaCALIFORNIA752002
Santa Cruz ICALIFORNIA541988
AthloneCALIFORNIA442007
Mesa GrandeCALIFORNIA432024
Yolla BollyCALIFORNIA402024
CopperopolisCALIFORNIA382024
LivermoreCALIFORNIA311991
GreenfieldCALIFORNIA302024
OnoCALIFORNIA292012
CordovaCALIFORNIA291981
LockwoodCALIFORNIA292024
PowayCALIFORNIA271980
ReddingCALIFORNIA271983
Red BluffCALIFORNIA262024
OrlandCALIFORNIA242022
Lake BerryessaCALIFORNIA232024
ShafterCALIFORNIA231989
JacksonCALIFORNIA231992
Anza 2CALIFORNIA232024
South LakeCALIFORNIA232006
TracyCALIFORNIA222009
Tracy 2CALIFORNIA222024

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