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

Pine Siskin In Coastal California

All regionsCoastal CaliforniaForest birds

Pine Siskin in Coastal California has fallen sharply: down 59% on the route-weighted index since 1970.

-59%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 →
32Routes 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 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 →

Pine Siskin has fallen sharply in Coastal California: down 59% on the route-weighted index since 1970.

Pine Siskin In Coastal California Population Forecast

If the recent trend holds, Pine Siskin in Coastal California is projected to fall about 51% by 2030 — from 1.3 in 2025 to a central estimate of 0.61 (95% range 0.00–2.3). A 5-year backtest shows a typical error of ±54.2%, with 80% of held-out values landing inside the 95% band.

-51%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 →
0.61Projected 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 →
0.00–2.395% 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 →
±54.2%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, Pine Siskin in Coastal California is projected to fall about 51% by 2030 — from 1.3 in 2025 to a central estimate of 0.61 (95% range 0.00–2.3). A 5-year backtest shows a typical error of ±54.2%, 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 →
20260.680.002.4
20270.660.002.4
20280.640.002.4
20290.630.002.3
20300.610.002.3

Routes In Coastal California

Routes recording Pine Siskin 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 →
ColmaCALIFORNIA381972
Point ReyesCALIFORNIA342025
Big BearCALIFORNIA251981
FairfaxCALIFORNIA162024
PescaderoCALIFORNIA112025
Lake HemetCALIFORNIA81976
Elsinore MtnCALIFORNIA41970
Lake CachumaCALIFORNIA41988
Yolla BollyCALIFORNIA41973
Mark WestCALIFORNIA42024
Lake SuccessCALIFORNIA31975
MoragaCALIFORNIA31988
Bartlett SpsCALIFORNIA31975
Yokohl ValCALIFORNIA21994
Mt PinosCALIFORNIA21985
Morro BayCALIFORNIA21991
CohassetCALIFORNIA22025
ValyermoCALIFORNIA22018
FallsvaleCALIFORNIA21975
Green ValleyCALIFORNIA21991
Glen EllenCALIFORNIA21976
WoodlandsCALIFORNIA22019
TomheadCALIFORNIA22008
Red BluffCALIFORNIA11969
Tres PinosCALIFORNIA11994

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