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

Clay-colored Sparrow Population Trend in Wisconsin

All statesGeneralists

Clay-colored Sparrow in Wisconsin has declined: down 45% on the route-weighted index since 1968.

-45%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 →
88Routes 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 Clay-colored 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 →

No notable trend signals for Clay-colored Sparrow in Wisconsin. See the full index history below.

Clay-colored Sparrow Population Forecast in Wisconsin

If the recent trend holds, Clay-colored Sparrow in Wisconsin is projected to rise about 117% by 2029 — from 1.1 in 2024 to a central estimate of 2.4 (95% range 1.3–3.5). A 5-year backtest shows a typical error of ±118.1%, with 0% of held-out values landing inside the 95% band.

+117%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 →
2.4Projected 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 →
1.3–3.595% 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 →
±118.1%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, Clay-colored Sparrow in Wisconsin is projected to rise about 117% by 2029 — from 1.1 in 2024 to a central estimate of 2.4 (95% range 1.3–3.5). A 5-year backtest shows a typical error of ±118.1%, with 0% 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 →
20252.41.33.5
20262.41.33.5
20272.41.33.5
20282.41.33.5
20292.41.33.5

Clay-colored Sparrow Survey Routes in Wisconsin

Routes recording Clay-colored 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 →
Iron River1520241967
Bayfield820241967
Hudson820241966
Weyerhauser720241966
Amnicon Falls720241998
Holway519891967
River Falls520241998
Grimms520212004
Union Twp420241967
Casco420241994
Omro 2420232006
Minong320231967
Wausaukee320231980
Cadott320241966
Stratford320241966
Saxeville320241969
Manitowoc320211968
Eden320212014
Meridean320241998
Buena Vista320231998
Grand View220241966
Land O Lakes220161976
Merrill220241966
Mcnaughton220101967
Esdaile220101974

Clay-colored Sparrow Population Trend in Other States

coloradoillinoisindianaiowamainemichiganminnesotamontananebraskanew-yorknorth-dakotapennsylvaniasouth-dakotautahwashingtonwyoming

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