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

Turkey Vulture Population Trend in Maine

All statesGeneralists

Turkey Vulture in Maine has surged: up 632% on the route-weighted index since 1983.

+632%Since 1983TrendPercent 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 →
37Routes 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 →
38YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Turkey Vulture 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 →

Turkey Vulture has surged in Maine: up 632% on the route-weighted index since 1983.

Turkey Vulture Population Forecast in Maine

If the recent trend holds, Turkey Vulture in Maine is projected to fall about 55% by 2029 — from 0.90 in 2024 to a central estimate of 0.40 (95% range 0.15–0.66). A 5-year backtest shows a typical error of ±40.5%, with 40% of held-out values landing inside the 95% band.

-55%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 →
0.40Projected 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 →
0.15–0.6695% 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 →
±40.5%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, Turkey Vulture in Maine is projected to fall about 55% by 2029 — from 0.90 in 2024 to a central estimate of 0.40 (95% range 0.15–0.66). A 5-year backtest shows a typical error of ±40.5%, with 40% of held-out values landing inside the 95% band.19812029
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 →
20250.370.120.62
20260.380.120.63
20270.390.130.64
20280.400.140.65
20290.400.150.66

Turkey Vulture Survey Routes in Maine

Routes recording Turkey Vulture 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 →
East Troy1120051986
Wilson Mills520242023
Cornville520242021
Hartford320241982
Kittery Pt220232018
Freedom220061995
Harmony220242016
Cooper220102006
Seboomook Lk220132003
Lake Moxie220192019
Horse Mtn220032003
Andover220172017
Westbrook120042004
Biddeford120061981
Newcastle120081996
Bethel120122012
Greenwood120221997
Reeds120232007
South Arm120141996
Otisfield Gr120152006
Bowdoin Ctr119911991
Brooks120131983
Eastbrook120222013
Aurora120212010
Brownfield 2120222014

Turkey Vulture Population Trend in Other States

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

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