BirdAnalyst
Species · BCR 15 · BBS 2025 Release · 1966–2024

Common Nighthawk In Sierra Nevada

All regionsSierra NevadaAerial insectivores

Common Nighthawk in Sierra Nevada has surged: up 142% on the route-weighted index since 1972.

+142%Since 1972TrendPercent 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 →
23Routes 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 →
54YearsYears 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 →

Common Nighthawk has surged in Sierra Nevada: up 142% on the route-weighted index since 1972.

Common Nighthawk In Sierra Nevada Population Forecast

If the recent trend holds, Common Nighthawk in Sierra Nevada is projected to fall about 23% by 2029 — from 1.6 in 2024 to a central estimate of 1.2 (95% range 0.11–2.3). A 5-year backtest shows a typical error of ±73.3%, with 100% of held-out values landing inside the 95% band.

-23%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 →
1.2Projected 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 →
0.11–2.395% 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 →
±73.3%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, Common Nighthawk in Sierra Nevada is projected to fall about 23% by 2029 — from 1.6 in 2024 to a central estimate of 1.2 (95% range 0.11–2.3). A 5-year backtest shows a typical error of ±73.3%, with 100% of held-out values landing inside the 95% band.19702029
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 →
20251.20.102.3
20261.20.102.3
20271.20.112.3
20281.20.112.3
20291.20.112.3

Routes In Sierra Nevada

Routes recording Common Nighthawk in Sierra Nevada.
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 →
Eagle LakeCALIFORNIA202024
GoumazCALIFORNIA192010
Hat CreekCALIFORNIA82018
Little TruckeeCALIFORNIA62023
Pine MountainCALIFORNIA62017
ChilcootCALIFORNIA62024
Lassen ParkCALIFORNIA41988
DownievilleCALIFORNIA32013
Chaos CraterCALIFORNIA32018
LumberyardCALIFORNIA22014
Tuolumne GroveCALIFORNIA22024
RivertonCALIFORNIA22007
ChesterCALIFORNIA22017
Meadow ValleyCALIFORNIA22023
Last ChanceCALIFORNIA22019
WestvilleCALIFORNIA12011
DardanelleCALIFORNIA12010
JohnsvilleCALIFORNIA11989
WoodfordsCALIFORNIA12024
Greenhorn MtCALIFORNIA11973
SattleyCALIFORNIA12019
Butte MeadowCALIFORNIA11992
GeneseeCALIFORNIA12024

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