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

Brown Creeper Population Trend in Connecticut

All statesForest birds

Brown Creeper in Connecticut has edged up: up 21% on the route-weighted index since 1971.

+21%Since 1971TrendPercent 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 →
19Routes 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 →
44YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Brown Creeper 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 Brown Creeper in Connecticut. See the full index history below.

Brown Creeper Population Forecast in Connecticut

If the recent trend holds, Brown Creeper in Connecticut is projected to fall about 84% by 2029 — from 0.67 in 2024 to a central estimate of 0.11 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±54.3%, with 80% of held-out values landing inside the 95% band.

-84%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 →
0.11Projected 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 →
0.00–0.4295% 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 →
±54.3%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, Brown Creeper in Connecticut is projected to fall about 84% by 2029 — from 0.67 in 2024 to a central estimate of 0.11 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±54.3%, with 80% of held-out values landing inside the 95% band.19672029
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 →
20250.120.000.43
20260.120.000.43
20270.120.000.42
20280.110.000.42
20290.110.000.42

Brown Creeper Survey Routes in Connecticut

Routes recording Brown Creeper 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 →
Granby320241989
Sherman219921976
Mystic119891976
E Hartland119841984
Buckingham120012001
Uncasville120142014
Woodstock119901971
Westbrook119921986
Willimantic120051974
No Woodbury119851967
Greenwich119841968
Danbury119721968
Warren120111974
Long Hill120171975
Mid Haddam119871975
New Hartford119871977
New Hartford120241995
Woodstock 2120242016
Warren 2120242013

Brown Creeper Population Trend in Other States

alaskaarizonacaliforniacoloradoidahoillinoisindianaiowamainemarylandmassachusettsmichiganminnesotamontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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