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

Say's Phoebe In Coastal California

All regionsCoastal CaliforniaAerial insectivores

Say's Phoebe in Coastal California has surged: up 102% on the route-weighted index since 1971.

+102%Since 1971TrendPercent 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 →
48Routes 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 →
55YearsYears 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 →

Say's Phoebe has surged in Coastal California: up 102% on the route-weighted index since 1971.

Say's Phoebe In Coastal California Population Forecast

If the recent trend holds, Say's Phoebe in Coastal California is projected to fall about 34% by 2029 — from 0.70 in 2024 to a central estimate of 0.47 (95% range 0.19–0.74). A 5-year backtest shows a typical error of ±43.5%, with 60% of held-out values landing inside the 95% band.

-34%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 →
0.47Projected 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 →
0.19–0.7495% 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 →
±43.5%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, Say's Phoebe in Coastal California is projected to fall about 34% by 2029 — from 0.70 in 2024 to a central estimate of 0.47 (95% range 0.19–0.74). A 5-year backtest shows a typical error of ±43.5%, with 60% 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 →
20250.440.160.71
20260.440.170.72
20270.450.170.73
20280.460.180.73
20290.470.190.74

Routes In Coastal California

Routes recording Say's Phoebe 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 →
Orange CoveCALIFORNIA82016
JacumbaCALIFORNIA72024
MorenoCALIFORNIA62024
Oak GroveCALIFORNIA62024
Green ValleyCALIFORNIA42022
Anza 2CALIFORNIA42024
San YsidroCALIFORNIA32019
Elsinore MtnCALIFORNIA32024
AnzaCALIFORNIA32003
VentucopaCALIFORNIA32001
Carrizo PlnCALIFORNIA32021
AthloneCALIFORNIA31976
South LakeCALIFORNIA32006
Mesa GrandeCALIFORNIA22024
Lockwood ValCALIFORNIA22018
Cp. PendletonCALIFORNIA22004
Cuyamaca PkCALIFORNIA22023
SangerCALIFORNIA22019
ArvinCALIFORNIA22018
Ora LomaCALIFORNIA21983
Hollister 2CALIFORNIA22022
TracyCALIFORNIA22006
Tracy 2CALIFORNIA22024
HughsonCALIFORNIA11981
Tres PinosCALIFORNIA11995

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