BirdAnalyst
Species · Delaware · BBS 2025 Release · 1966–2024

Chuck-will's-widow Population Trend in Delaware

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Chuck-will's-widow in Delaware has increased: up 42% on the route-weighted index since 1968.

+42%Since 1968TrendPercent 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 →
7Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
47YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Chuck-will's-widow Trends in DelawareNotable 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 Chuck-will's-widow in Delaware. See the full index history below.

Chuck-will's-widow Population Forecast in Delaware

If the recent trend holds, Chuck-will's-widow in Delaware is projected to stay roughly flat through 2027, near 0.39 (95% range 0.00–0.84). A 5-year backtest shows a typical error of ±72.8%, with 100% of held-out values landing inside the 95% band.

-4%Change by 2027TrendPercent 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 →
0.39Projected 2027 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.8495% 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 →
±72.8%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, Chuck-will's-widow in Delaware is projected to stay roughly flat through 2027, near 0.39 (95% range 0.00–0.84). A 5-year backtest shows a typical error of ±72.8%, with 100% of held-out values landing inside the 95% band.19662027
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 →
20230.380.000.83
20240.380.000.83
20250.380.000.83
20260.380.000.84
20270.390.000.84

Chuck-will's-widow Survey Routes in Delaware

Routes recording Chuck-will's-widow in Delaware.
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 →
Milton320131968
Holleyville220041966
Georgetown220222001
Harrington120041984
Frederica119671967
Frankford119781966
Lowes Xrds119761976

Chuck-will's-widow Population Trend in Other States

alabamaarkansasfloridageorgiaillinoisindianakansaskentuckylouisianamarylandmississippimissourinebraskanew-jerseynorth-carolinaohiooklahomasouth-carolinatennesseetexasvirginiawest-virginia

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