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

Red-winged Blackbird Population Trend in Delaware

All statesGeneralists

Red-winged Blackbird in Delaware has edged down: down 21% on the route-weighted index since 1968.

-21%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 →
17Routes 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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Red-winged Blackbird 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 Red-winged Blackbird in Delaware. See the full index history below.

Red-winged Blackbird Population Forecast in Delaware

If the recent trend holds, Red-winged Blackbird in Delaware is projected to rise about 35% by 2029 — from 42 in 2024 to a central estimate of 57 (95% range 17–97). A 5-year backtest shows a typical error of ±45.1%, with 100% of held-out values landing inside the 95% band.

+35%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 →
57Projected 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 →
17–9795% 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 →
±45.1%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, Red-winged Blackbird in Delaware is projected to rise about 35% by 2029 — from 42 in 2024 to a central estimate of 57 (95% range 17–97). A 5-year backtest shows a typical error of ±45.1%, with 100% of held-out values landing inside the 95% band.19662029
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 →
2025571798
2026571798
2027571798
2028571797
2029571797

Red-winged Blackbird Survey Routes in Delaware

Routes recording Red-winged Blackbird 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 →
Blackbird10020241994
Harrington8120241966
Bethany Bch7719901966
Mt Pleasant5020191966
Milton 23720172017
Wilmington3520141966
Lowes Xrds3519911966
Dover3419871966
Pepperbox2420161998
Milton1820161966
Holleyville 21320242006
Georgetown1320221992
Pepperbox 21320242017
Holleyville1020041966
Millsboro420242017
Frankford320121966
Frederica220141966

Red-winged Blackbird Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutfloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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