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Species · Connecticut · BBS 2026 Release · 1966–2025

Indigo Bunting Population Trend in Connecticut

All statesForest birds

Indigo Bunting in Connecticut has edged down: down 20% on the route-weighted index since 1968.

-20%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 →
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 Indigo Bunting 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 →

No notable trend signals for Indigo Bunting in Connecticut. See the full index history below.

Indigo Bunting Population Forecast in Connecticut

If the recent trend holds, Indigo Bunting in Connecticut is projected to fall about 36% by 2030 — from 2.8 in 2025 to a central estimate of 1.8 (95% range 0.00–4.6). A 5-year backtest shows a typical error of ±32.4%, with 100% of held-out values landing inside the 95% band.

-36%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 →
1.8Projected 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 →
0.00–4.695% 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 →
±32.4%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, Indigo Bunting in Connecticut is projected to fall about 36% by 2030 — from 2.8 in 2025 to a central estimate of 1.8 (95% range 0.00–4.6). A 5-year backtest shows a typical error of ±32.4%, with 100% 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 →
20261.80.004.7
20271.80.004.7
20281.80.004.6
20291.80.004.6
20301.80.004.6

Indigo Bunting Survey Routes in Connecticut

Routes recording Indigo Bunting 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 →
Long Hill720191972
Warren620111972
Woodstock 2620252016
Uncasville520251973
Granby520251988
New Hartford419861972
Mystic320231973
Danbury320171968
E Hartland219921966
Buckingham220221966
Woodstock219961969
Willimantic220181967
No Woodbury220251967
New Hartford220241994
Warren 2220252022
Westbrook120251974
Sherman120191972
Greenwich120141968
Mid Haddam120251977
Southington120191973

Indigo Bunting Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradodelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawest-virginiawisconsinwyoming

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