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

Brown Creeper Population Trend in Maine

All statesForest birds

Brown Creeper in Maine has surged: up 120% on the route-weighted index since 1968.

+120%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 →
63Routes 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 →
55YearsYears 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 MaineNotable 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 →

Brown Creeper has surged in Maine: up 120% on the route-weighted index since 1968.

Brown Creeper Population Forecast in Maine

If the recent trend holds, Brown Creeper in Maine is projected to fall about 30% by 2029 — from 0.79 in 2024 to a central estimate of 0.55 (95% range 0.15–0.94). A 5-year backtest shows a typical error of ±38.6%, with 40% of held-out values landing inside the 95% band.

-30%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 →
0.55Projected 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 →
0.15–0.9495% 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 →
±38.6%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 Maine is projected to fall about 30% by 2029 — from 0.79 in 2024 to a central estimate of 0.55 (95% range 0.15–0.94). A 5-year backtest shows a typical error of ±38.6%, with 40% 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 →
20250.520.120.92
20260.530.130.92
20270.540.140.93
20280.540.140.94
20290.550.150.94

Brown Creeper Survey Routes in Maine

Routes recording Brown Creeper in Maine.
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 →
Pillsbury Pd519681968
Brownfield 2520242015
Big Twenty320071993
Wilson Mills220181983
Nesowadnehun220211990
East Troy220181983
Topsfield219911990
Harmony220221968
Clayton Lake 2220102010
Eastbrook220231993
Heron Lake220031994
Aurora220211996
Carrying Pl220241980
Wytopitlock219971990
Medway220181991
Grnd Lk Strm219921990
Clayton Lake220011977
Stacyville220232023
Andover220212010
Yankeetuladi220071994
Rome220241996
Westbrook119931979
Biddeford119941987
Kittery Pt120221966
Newcastle120231990

Brown Creeper Population Trend in Other States

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

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