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Species · Connecticut · BBS 2026 Release · 1966–2025

Great Crested Flycatcher Population Trend in Connecticut

All statesAerial insectivores

Great Crested Flycatcher in Connecticut has risen sharply: up 56% on the route-weighted index since 1968.

+56%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 Great Crested Flycatcher 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 increasecomputed 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 →

Great Crested Flycatcher has risen sharply in Connecticut: up 56% on the route-weighted index since 1968.

Great Crested Flycatcher Population Forecast in Connecticut

If the recent trend holds, Great Crested Flycatcher in Connecticut is projected to fall about 18% by 2030 — from 3.8 in 2025 to a central estimate of 3.1 (95% range 1.6–4.6). A 5-year backtest shows a typical error of ±18.7%, with 100% of held-out values landing inside the 95% band.

-18%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 →
3.1Projected 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 →
1.6–4.695% 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 →
±18.7%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, Great Crested Flycatcher in Connecticut is projected to fall about 18% by 2030 — from 3.8 in 2025 to a central estimate of 3.1 (95% range 1.6–4.6). A 5-year backtest shows a typical error of ±18.7%, 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 →
20263.11.64.5
20273.11.64.5
20283.11.64.5
20293.11.64.5
20303.11.64.6

Great Crested Flycatcher Survey Routes in Connecticut

Routes recording Great Crested Flycatcher 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 →
Woodstock 21220252016
Warren620111972
Long Hill620191972
New Hartford519871972
Granby520251988
Willimantic420181967
Southington420251973
Uncasville320251973
Woodstock320071968
E Hartland219921966
Westbrook220251972
Mid Haddam220251973
Mystic120231973
Buckingham120221966
No Woodbury120251967
Sherman120191973
Greenwich120181967
Danbury120231969
New Hartford120221994
Warren 2120252013

Great Crested Flycatcher Population Trend in Other States

alabamaarkansascoloradodelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsin

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