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

Red-winged Blackbird Population Trend in Connecticut

All statesGeneralists

Red-winged Blackbird in Connecticut has collapsed: down 75% on the route-weighted index since 1968.

-75%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 →
20Routes 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 ConnecticutNotable 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 Connecticut: down 75% on the route-weighted index since 1968.

Red-winged Blackbird Population Forecast in Connecticut

If the recent trend holds, Red-winged Blackbird in Connecticut is projected to fall about 41% by 2029 — from 17 in 2024 to a central estimate of 10 (95% range 0.00–33). A 5-year backtest shows a typical error of ±37.6%, with 100% of held-out values landing inside the 95% band.

-41%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 →
10Projected 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 →
0.00–3395% 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 →
±37.6%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 Connecticut is projected to fall about 41% by 2029 — from 17 in 2024 to a central estimate of 10 (95% range 0.00–33). A 5-year backtest shows a typical error of ±37.6%, 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 →
2025130.0036
2026120.0035
2027120.0034
2028110.0033
2029100.0033

Red-winged Blackbird Survey Routes in Connecticut

Routes recording Red-winged Blackbird in Connecticut.
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 →
Warren12020111972
Sherman8320191972
New Hartford4819871972
Willimantic4620181967
Woodstock 23520242016
Mystic3420231973
Woodstock3220071968
Uncasville3120241973
Mid Haddam2520241973
Westbrook2320241969
Long Hill1720191972
Granby1320241988
Buckingham1120221966
No Woodbury920241967
Danbury920231968
Warren 2920242012
Southington820241973
E Hartland519921966
New Hartford220241994
Greenwich120181967

Red-winged Blackbird Population Trend in Other States

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

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