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Species · Wisconsin · BBS 2025 Release · 1966–2024

Wood Thrush Population Trend in Wisconsin

All statesForest birds

Wood Thrush in Wisconsin has risen sharply: up 75% on the route-weighted index since 1968.

+75%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 →
96Routes 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 Wood Thrush 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 →

Wood Thrush has risen sharply in Wisconsin: up 75% on the route-weighted index since 1968.

Wood Thrush Population Forecast in Wisconsin

If the recent trend holds, Wood Thrush in Wisconsin is projected to fall about 30% by 2029 — from 2.6 in 2024 to a central estimate of 1.8 (95% range 1.1–2.6). A 5-year backtest shows a typical error of ±35.7%, with 20% 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 →
1.8Projected 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 →
1.1–2.695% 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 →
±35.7%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, Wood Thrush in Wisconsin is projected to fall about 30% by 2029 — from 2.6 in 2024 to a central estimate of 1.8 (95% range 1.1–2.6). A 5-year backtest shows a typical error of ±35.7%, with 20% 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 →
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Wood Thrush Survey Routes in Wisconsin

Routes recording Wood Thrush 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 →
Weirgor Springs3020241999
Amberg1620241980
Mellen1320241998
Chaffey1020241967
Bayfield1020241972
Mather920231966
Land O Lakes820091969
Wausaukee820241980
Hatfield819981971
Gresham820241998
Cumberland720241967
Popple River720241967
Cadott720241966
Flambeau720241999
Iron River620241971
Stevens Pt620231966
Stetsonville620241990
Hollister520241967
Gilman420241966
Crandon420241967
Trempealeau420231972
Oconto Falls420231968
Clintonville420241968
Amnicon Falls420241998
Cavour420242000

Wood Thrush Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginia

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