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

Lesser Nighthawk In Coastal California

All regionsCoastal CaliforniaAerial insectivores

Lesser Nighthawk in Coastal California has declined: down 27% on the route-weighted index since 1970.

-27%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 →
22Routes 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 →
52YearsYears 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 Lesser Nighthawk in Coastal California. See the full index history below.

Lesser Nighthawk In Coastal California Population Forecast

If the recent trend holds, Lesser Nighthawk in Coastal California is projected to fall about 17% by 2029 — from 0.11 in 2024 to a central estimate of 0.09 (95% range 0.00–0.23). A 5-year backtest shows a typical error of ±193.7%, with 100% of held-out values landing inside the 95% band.

-17%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 →
0.09Projected 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 →
0.00–0.2395% 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 →
±193.7%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, Lesser Nighthawk in Coastal California is projected to fall about 17% by 2029 — from 0.11 in 2024 to a central estimate of 0.09 (95% range 0.00–0.23). A 5-year backtest shows a typical error of ±193.7%, 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 →
20250.090.000.24
20260.090.000.24
20270.090.000.24
20280.090.000.23
20290.090.000.23

Routes In Coastal California

Routes recording Lesser Nighthawk 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 →
RumseyCALIFORNIA62008
AtwaterCALIFORNIA52004
CopperopolisCALIFORNIA41994
Cuyamaca PkCALIFORNIA32024
Ora LomaCALIFORNIA31981
PenningtonCALIFORNIA21976
MaricopaCALIFORNIA22024
AnzaCALIFORNIA22003
VentucopaCALIFORNIA22002
OrovilleCALIFORNIA22006
HughsonCALIFORNIA12016
GravesboroCALIFORNIA11995
BakersfieldCALIFORNIA12005
Oak GroveCALIFORNIA12023
CoalingaCALIFORNIA11990
Lake SuccessCALIFORNIA11976
CohassetCALIFORNIA11991
OrlandCALIFORNIA12011
Mesa GrandeCALIFORNIA12000
JacumbaCALIFORNIA12023
ArvinCALIFORNIA11985
TranquillityCALIFORNIA11986

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