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Species · Indiana · BBS 2025 Release · 1966–2024

Warbling Vireo Population Trend in Indiana

All statesForest birds

Warbling Vireo in Indiana has surged: up 95% on the route-weighted index since 1968.

+95%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 →
68Routes 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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Warbling Vireo Trends in IndianaNotable 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 →

Warbling Vireo has surged in Indiana: up 95% on the route-weighted index since 1968.

Warbling Vireo Population Forecast in Indiana

If the recent trend holds, Warbling Vireo in Indiana is projected to rise about 55% by 2029 — from 3.7 in 2024 to a central estimate of 5.8 (95% range 4.2–7.3). A 5-year backtest shows a typical error of ±19.6%, with 80% 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 →
5.8Projected 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 →
4.2–7.395% 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 →
±19.6%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 →
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 →
20255.64.07.2
20265.74.17.2
20275.74.17.3
20285.74.27.3
20295.84.27.3

Warbling Vireo Survey Routes in Indiana

Routes recording Warbling Vireo in Indiana.
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 →
Wallace1520241999
Wabash1020241981
Spencer1020241967
Brazil920241966
Packertown 2820242005
Middlebury720241989
Packertown720041967
Thorntown720241982
Witts Station720242000
Newberry720241999
Hebron620221966
Fowler620221967
Friendswood620241986
Washington620241987
Indian Spgs620241984
Clear Spring620241981
Lagrange620241999
Anderson620242000
Pimento520241981
Frankfort520222000
Montpelier520242018
Maplewood520212000
Portage520032000
Lakeville520241997
Knox420241981

Warbling Vireo Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawareidahoillinoisiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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