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Species · Maryland · BBS 2026 Release · 1966–2025

Red-winged Blackbird Population Trend in Maryland

All statesWetland birds

Red-winged Blackbird in Maryland has declined: down 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 →
76Routes 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 →
59YearsYears 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 MarylandNotable 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 Maryland. See the full index history below.

Red-winged Blackbird Population Forecast in Maryland

If the recent trend holds, Red-winged Blackbird in Maryland is projected to fall about 44% by 2030 — from 52 in 2025 to a central estimate of 29 (95% range 14–44). A 5-year backtest shows a typical error of ±33.4%, with 60% of held-out values landing inside the 95% band.

-44%Change by 2030TrendPercent 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 →
29Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
14–4495% 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 →
±33.4%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 Maryland is projected to fall about 44% by 2030 — from 52 in 2025 to a central estimate of 29 (95% range 14–44). A 5-year backtest shows a typical error of ±33.4%, with 60% of held-out values landing inside the 95% band.19662030
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 →
2026311647
2027311646
2028301545
2029301445
2030291444

Red-winged Blackbird Survey Routes in Maryland

Routes recording Red-winged Blackbird in Maryland.
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 →
Honga32020251966
Madison27120251966
Cokesbury12720251966
Grove Neck11119961992
Piney Neck10620251966
Easton9420251966
Melitota9220251966
Williamsport9020251966
Emmitsburg8620251966
Olney7820251966
Golden Hill7820251966
Bachman Mill6320251966
Earlton5820242014
Jennings5620251995
Harmony5520171966
Finzel5220251995
Mt Nebo4919911969
Ijamsville4920251986
Pleasant Val4520251966
Millington4020251966
Matthews4020251966
Forest Grove3620232011
Wolfsville3520251966
Fruitland3319981966
Madonna3320222009

Red-winged Blackbird Population Trend in Other States

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

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.