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

Red-winged Blackbird Population Trend in Pennsylvania

All statesGeneralists

Red-winged Blackbird in Pennsylvania has fallen sharply: down 63% on the route-weighted index since 1968.

-63%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 →
135Routes 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 PennsylvaniaNotable 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 declinecomputed 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 →

Red-winged Blackbird has fallen sharply in Pennsylvania: down 63% on the route-weighted index since 1968.

Red-winged Blackbird Population Forecast in Pennsylvania

If the recent trend holds, Red-winged Blackbird in Pennsylvania is projected to fall about 45% by 2029 — from 36 in 2024 to a central estimate of 20 (95% range 0.00–43). A 5-year backtest shows a typical error of ±42.8%, with 100% of held-out values landing inside the 95% band.

-45%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 →
20Projected 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 →
0.00–4395% 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 →
±42.8%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, Red-winged Blackbird in Pennsylvania is projected to fall about 45% by 2029 — from 36 in 2024 to a central estimate of 20 (95% range 0.00–43). A 5-year backtest shows a typical error of ±42.8%, 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 →
2025241.447
2026230.3846
2027220.0045
2028210.0044
2029200.0043

Red-winged Blackbird Survey Routes in Pennsylvania

Routes recording Red-winged Blackbird in Pennsylvania.
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 →
Portersville25019881973
Akeley20319791966
Mifflintown13920241966
Harmonsburg13220231966
Clover12220241981
Ralston10919781966
Rector9819771966
Little Marsh9720241967
Drehersville8819991966
Plesant Grov8720241966
Duvall8520211974
Ferris Crnrs8220241966
N Washington8120241967
Doubling Gap8119771966
Kittanning8020241972
Arnot7920241969
Sugar Grove7920241980
Aspers7819891968
Shelocta7420241968
Honesdale7320241972
Wakena7320231969
West Grove7319961966
Drehersville 27220242000
Sigel7020241981
Teepleville6820241966

Red-winged Blackbird Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonrhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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