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

American Coot In Coastal California

All regionsCoastal CaliforniaWetland birds

American Coot in Coastal California has declined: down 48% on the route-weighted index since 1970.

-48%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 →
77Routes 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 →

No notable trend signals for American Coot in Coastal California. See the full index history below.

Forecast

If the recent trend holds, American Coot in Coastal California is projected to fall about 76% by 2029 — from 0.74 in 2024 to a central estimate of 0.18 (95% range 0.00–1.8). A 5-year backtest shows a typical error of ±345%, with 100% of held-out values landing inside the 95% band.

-76%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 →
0.18Projected 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 →
0.00–1.895% 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 →
±345%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, American Coot in Coastal California is projected to fall about 76% by 2029 — from 0.74 in 2024 to a central estimate of 0.18 (95% range 0.00–1.8). A 5-year backtest shows a typical error of ±345%, 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 →
20250.310.001.9
20260.280.001.9
20270.250.001.9
20280.210.001.8
20290.180.001.8

Routes In Coastal California

Routes recording American Coot 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 →
Carrizo PlnCALIFORNIA881978
Cp. PendletonCALIFORNIA451991
Big BearCALIFORNIA161986
CoyoteCALIFORNIA132024
AthloneCALIFORNIA101989
LockwoodCALIFORNIA92024
CollegevilleCALIFORNIA81987
Green ValleyCALIFORNIA82012
VentucopaCALIFORNIA71997
GlennCALIFORNIA72015
Mesa GrandeCALIFORNIA62005
Ora LomaCALIFORNIA62023
PescaderoCALIFORNIA52024
PolomaCALIFORNIA52023
RumseyCALIFORNIA41988
Tres PinosCALIFORNIA42002
Foster ParkCALIFORNIA41994
Lake HemetCALIFORNIA41981
Mark WestCALIFORNIA41978
CopperopolisCALIFORNIA42018
Harbor LakeCALIFORNIA31991
MorenoCALIFORNIA32024
El ToroCALIFORNIA31980
SisquocCALIFORNIA31975
ShafterCALIFORNIA31989

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