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Species · Connecticut · BBS 2025 Release · 1966–2024

Black-capped Chickadee Population Trend in Connecticut

All statesForest birds

Black-capped Chickadee in Connecticut has increased: up 36% on the route-weighted index since 1968.

+36%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 Black-capped Chickadee 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 Black-capped Chickadee in Connecticut. See the full index history below.

Black-capped Chickadee Population Forecast in Connecticut

If the recent trend holds, Black-capped Chickadee in Connecticut is projected to rise about 98% by 2029 — from 9.8 in 2024 to a central estimate of 19 (95% range 12–27). A 5-year backtest shows a typical error of ±84.5%, with 0% of held-out values landing inside the 95% band.

+98%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 →
19Projected 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 →
12–2795% 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 →
±84.5%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, Black-capped Chickadee in Connecticut is projected to rise about 98% by 2029 — from 9.8 in 2024 to a central estimate of 19 (95% range 12–27). A 5-year backtest shows a typical error of ±84.5%, with 0% 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 →
2025191226
2026191226
2027191226
2028191226
2029191227

Black-capped Chickadee Survey Routes in Connecticut

Routes recording Black-capped Chickadee 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 →
Warren5820111972
Willimantic3220181967
Mystic1720231973
Long Hill1720191972
E Hartland1619921966
Buckingham1620221966
Woodstock 21620242016
Uncasville1420241973
Sherman1220191972
Greenwich1220181967
New Hartford1219871972
Warren 21120242012
Granby1120241988
Westbrook1020241969
Danbury1020231968
Mid Haddam920241973
Woodstock820071968
Southington720241973
New Hartford620241994
No Woodbury420241967

Black-capped Chickadee Population Trend in Other States

alaskacaliforniacoloradoidahoillinoisindianaiowakansasmainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotatennesseeutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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