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

Northern Bobwhite Population Trend in Wisconsin

All statesGrassland birds

Northern Bobwhite in Wisconsin has collapsed: down 96% on the route-weighted index since 1968.

-96%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 →
61Routes 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 Northern Bobwhite 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 declinecomputed 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 →

Northern Bobwhite has collapsed in Wisconsin: down 96% on the route-weighted index since 1968.

Northern Bobwhite Population Forecast in Wisconsin

If the recent trend holds, Northern Bobwhite in Wisconsin is projected to fall about 80% by 2029 — from 0.07 in 2024 to a central estimate of 0.01 (95% range 0.00–1.3). A 5-year backtest shows a typical error of ±1136.8%, with 100% of held-out values landing inside the 95% band.

-80%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 →
0.01Projected 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 →
0.00–1.395% 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 →
±1136.8%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, Northern Bobwhite in Wisconsin is projected to fall about 80% by 2029 — from 0.07 in 2024 to a central estimate of 0.01 (95% range 0.00–1.3). A 5-year backtest shows a typical error of ±1136.8%, 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 →
20250.110.001.4
20260.090.001.3
20270.060.001.3
20280.040.001.3
20290.010.001.3

Northern Bobwhite Survey Routes in Wisconsin

Routes recording Northern Bobwhite 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 →
Briggsville1220071999
Meridean520121998
Viroqua420071970
Fall River420241967
Esdaile319691966
Hudson219821969
Highland220042000
Rib Lake219781978
Washington I220192011
Saxeville220011969
Clintonville220011993
Kendall220071967
N Freedom220051966
Pardeeville220041967
Princeton220101966
Prairie Du Chien220071998
Dresser119791975
Union Twp119761976
Loraine120082007
Rhinelander119981998
Weyerhauser120181973
Couderay119851985
Gilman120081990
Omro 2120072003
Mcnaughton119971997

Northern Bobwhite Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawashingtonwest-virginiawyoming

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