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Species · Wisconsin · BBS 2025 Release · 1966–2024

Warbling Vireo Population Trend in Wisconsin

All statesForest birds

Warbling Vireo in Wisconsin has edged down: down 16% on the route-weighted index since 1968.

-16%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 →
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 →
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 WisconsinNotable 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 Warbling Vireo in Wisconsin. See the full index history below.

Warbling Vireo Population Forecast in Wisconsin

If the recent trend holds, Warbling Vireo in Wisconsin is projected to stay roughly flat through 2029, near 3.2 (95% range 1.8–4.6). A 5-year backtest shows a typical error of ±24.9%, with 100% of held-out values landing inside the 95% band.

-4%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 →
3.2Projected 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 →
1.8–4.695% 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 →
±24.9%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, Warbling Vireo in Wisconsin is projected to stay roughly flat through 2029, near 3.2 (95% range 1.8–4.6). A 5-year backtest shows a typical error of ±24.9%, 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 →
20253.31.84.7
20263.31.84.7
20273.21.84.7
20283.21.84.7
20293.21.84.6

Warbling Vireo Survey Routes in Wisconsin

Routes recording Warbling Vireo 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 →
Grimms1920211998
Viroqua1620241966
Trempealeau1520241966
Fall River1420241966
Stratford1320241966
Annaton1320241998
Paris1220241966
Briggsville1220241999
Newburg Crns1120231966
Kendall1120231967
Wiota1120241966
Prairie Du Chien1120241998
Eden1020241966
Hazel Green1020241966
Beloit1020241998
River Falls920241998
Kiel920222000
Eagle River720101966
Pardeeville720241968
N Andover720241967
Cumberland620241966
Wausaukee620101980
Omro620011966
Casco620241967
N Freedom620241966

Warbling Vireo Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawareidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawyoming

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