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

Turkey Vulture Population Trend in Wisconsin

All statesGeneralists

Turkey Vulture in Wisconsin has surged: up 60× on the route-weighted index since 1969.

60×Since 1969TrendPercent 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 →
94Routes 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 →
53YearsYears 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 WisconsinNotable 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 Wisconsin: up 60× on the route-weighted index since 1969.

Turkey Vulture Population Forecast in Wisconsin

If the recent trend holds, Turkey Vulture in Wisconsin is projected to stay roughly flat through 2029, near 2.0 (95% range 1.2–2.9). A 5-year backtest shows a typical error of ±16.4%, with 100% of held-out values landing inside the 95% band.

+3%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 →
2.0Projected 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 →
1.2–2.995% 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 →
±16.4%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 Wisconsin is projected to stay roughly flat through 2029, near 2.0 (95% range 1.2–2.9). A 5-year backtest shows a typical error of ±16.4%, with 100% 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 →
20251.91.02.8
20261.91.12.8
20272.01.12.8
20282.01.12.9
20292.01.22.9

Turkey Vulture Survey Routes in Wisconsin

Routes recording Turkey Vulture in Wisconsin.
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 →
Paris2020231996
Mukwonago 21720242005
Hazel Green1220242010
Dresser1020242004
Brownsville1020241983
Prairie Du Chien1020241998
Annaton1020242000
Trempealeau720241985
Hudson620231999
Esdaile620241966
N Freedom620241968
Raymond620221998
Highland620242001
Rib Lake520171984
Clintonville520241986
Newburg Crns520241995
N Andover520241988
Phillips420231995
Viroqua420241966
Kendall420231982
Rolling Pr420222007
Beaver Dam420232004
Briggsville420242007
Iron River320222000
Union Twp320211988

Turkey Vulture Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawyoming

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