BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Lesser Nighthawk

CaprimulgidaeAerial insectivoresChordeiles acutipennis

Lesser Nighthawk has risen sharply: up 73% on the route-weighted index since 1969.

+73%Since 1969TrendPercent 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 →
237RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
57Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Lesser Nighthawk

The Lesser Nighthawk (Chordeiles acutipennis) is a North American member of the Nightjars & Nighthawks (Caprimulgidae). In this analysis it is grouped with the aerial insectivores.

Size
7.5–12 in long (19–30 cm) — a cryptic, big-mouthed bird (typical for the family)
Habitat
Open airspace over fields, water and towns; nests in cavities, earthen banks or on structures.
Diet
Flying insects caught on the wing.
Range
Recorded on 237 Breeding Bird Survey routes across 6 states, most concentrated in the Sonoran and Mojave Deserts.
Family
Caprimulgidae · Aerial insectivores

Notable Lesser Nighthawk TrendsNotable 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 →

Lesser Nighthawk has risen sharply in surveyed states: up 73% on the route-weighted index since 1969.

Lesser Nighthawk Population Forecast

If the recent trend holds, Lesser Nighthawk is projected to rise about 80% by 2029 — from 0.11 in 2024 to a central estimate of 0.19 (95% range 0.10–0.28). A 5-year backtest shows a typical error of ±49.8%, with 80% of held-out values landing inside the 95% band.

+80%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 →
0.19Projected 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 →
0.10–0.2895% 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 →
±49.8%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 is projected to rise about 80% by 2029 — from 0.11 in 2024 to a central estimate of 0.19 (95% range 0.10–0.28). A 5-year backtest shows a typical error of ±49.8%, with 80% of held-out values landing inside the 95% band.19672029
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 →
20250.190.100.28
20260.190.100.28
20270.190.100.28
20280.190.100.28
20290.190.100.28

Where the Lesser Nighthawk Is Detected

BBS routes recording Lesser Nighthawk, sized by most recent count.

Lesser Nighthawk Population Trend by State

Lesser Nighthawk population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Arizona+106%197054
California-23%197055
Nevada-84%197411
New Mexico+76%197022
Texas-24%196994
Utahinsufficient datan/a1

Lesser Nighthawk Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Lesser Nighthawk population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Shortgrass Prairie+32%20058
Edwards Plateau-2%19748
Oaks and Prairies-86%19719
Coastal California-27%197022
Sonoran and Mojave Deserts+83%197067
Sierra Madre Occidental+14%197020
Chihuahuan Desert+11%196948
Tamaulipan Brushlands-54%196928
Gulf Coastal Prairie-48%197211

Lesser Nighthawk Conservation Status

Our route-weighted index shows it up about 73% since 1969. Aerial insectivores have fallen sharply across the continent, a decline widely linked to dwindling insect prey.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.