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

Lark Sparrow Population Trend in Wisconsin

All statesGrassland birds

Lark Sparrow in Wisconsin has surged: up 120% on the route-weighted index since 1972.

+120%Since 1972TrendPercent 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 →
18Routes 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 →
39YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Lark Sparrow 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 →

Lark Sparrow has surged in Wisconsin: up 120% on the route-weighted index since 1972.

Lark Sparrow Population Forecast in Wisconsin

If the recent trend holds, Lark Sparrow in Wisconsin is projected to stay roughly flat through 2029, near 0.10 (95% range 0.03–0.17). A 5-year backtest shows a typical error of ±55.4%, with 100% of held-out values landing inside the 95% band.

-10%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 →
0.10Projected 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 →
0.03–0.1795% 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 →
±55.4%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, Lark Sparrow in Wisconsin is projected to stay roughly flat through 2029, near 0.10 (95% range 0.03–0.17). A 5-year backtest shows a typical error of ±55.4%, with 100% of held-out values landing inside the 95% band.19702029
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 →
20250.090.030.16
20260.100.030.16
20270.100.030.17
20280.100.030.17
20290.100.030.17

Lark Sparrow Survey Routes in Wisconsin

Routes recording Lark Sparrow 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 →
Union Twp620232008
Meridean320242010
Beloit220092009
Hatfield219791970
N Freedom220241982
Princeton220141970
Fall River220242023
Prairie Du Chien220141999
Briggsville220242006
Trempealeau120182018
Minong120112011
Grand View119941994
Cadott120112006
Montreal119841984
Cumberland120132013
Oconto Falls119901972
Bashaw120232015
Buena Vista120222022

Lark Sparrow Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoidahoillinoisindianaiowakansaskentuckylouisianaminnesotamississippimissourimontananebraskanevadanew-mexiconorth-dakotaohiooklahomaoregonsouth-dakotatennesseetexasutahwashingtonwyoming

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