BirdAnalyst
Species · Connecticut · BBS 2026 Release · 1966–2025

Chipping Sparrow Population Trend in Connecticut

All statesForest birds

Chipping Sparrow in Connecticut has increased: up 28% on the route-weighted index since 1968.

+28%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 Chipping Sparrow 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 Chipping Sparrow in Connecticut. See the full index history below.

Chipping Sparrow Population Forecast in Connecticut

If the recent trend holds, Chipping Sparrow in Connecticut is projected to rise about 39% by 2030 — from 26 in 2025 to a central estimate of 36 (95% range 24–47). A 5-year backtest shows a typical error of ±42.1%, with 40% of held-out values landing inside the 95% band.

+39%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 →
36Projected 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 →
24–4795% 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 →
±42.1%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, Chipping Sparrow in Connecticut is projected to rise about 39% by 2030 — from 26 in 2025 to a central estimate of 36 (95% range 24–47). A 5-year backtest shows a typical error of ±42.1%, with 40% 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 →
2026342346
2027352346
2028352446
2029352447
2030362447

Chipping Sparrow Survey Routes in Connecticut

Routes recording Chipping Sparrow 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 →
Warren7720111972
Uncasville5220251973
Sherman4120191972
Mid Haddam3420251973
Willimantic3320181967
Greenwich3320181967
Woodstock 23220252016
Long Hill3120191972
Woodstock3020071968
New Hartford2220241994
Granby2220251988
No Woodbury2120251967
Buckingham2020221966
New Hartford1819871972
Warren 21720252012
Mystic1520231973
Westbrook1420251969
E Hartland1319921966
Danbury1320231968
Southington1320251973

Chipping Sparrow Population Trend in Other States

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

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