BirdAnalyst
Species · BCR 12 · BBS 2026 Release · 1966–2025

Clay-colored Sparrow In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionGrassland birds

Clay-colored Sparrow in Boreal Hardwood Transition has declined: down 34% on the route-weighted index since 1968.

-34%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 →
105Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
59YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 Boreal Hardwood Transition. See the full index history below.

Clay-colored Sparrow In Boreal Hardwood Transition Population Forecast

If the recent trend holds, Clay-colored Sparrow in Boreal Hardwood Transition is projected to rise about 55% by 2030 — from 2.0 in 2025 to a central estimate of 3.1 (95% range 1.7–4.5). A 5-year backtest shows a typical error of ±77.7%, with 0% of held-out values landing inside the 95% band.

+55%Change by 2030TrendPercent 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 →
3.1Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
1.7–4.595% 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 →
±77.7%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, Clay-colored Sparrow in Boreal Hardwood Transition is projected to rise about 55% by 2030 — from 2.0 in 2025 to a central estimate of 3.1 (95% range 1.7–4.5). A 5-year backtest shows a typical error of ±77.7%, with 0% of held-out values landing inside the 95% band.19662030
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 →
20263.11.74.5
20273.11.74.5
20283.11.74.5
20293.11.74.5
20303.11.74.5

Routes In Boreal Hardwood Transition

Routes recording Clay-colored Sparrow in Boreal Hardwood Transition.
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 →
BagleyMINNESOTA322006
GreenbushMINNESOTA302025
DebsMINNESOTA182025
PickfordMICHIGAN172025
Amnicon FallsWISCONSIN132025
Iron RiverWISCONSIN102025
Little ForkMINNESOTA92024
BrainerdMINNESOTA82024
BackusMINNESOTA72025
BayfieldWISCONSIN72025
HerronMICHIGAN62016
Pine RiverMINNESOTA62025
Nett LakeMINNESOTA62024
GilmanWISCONSIN62025
WilsonMICHIGAN52010
MinongWISCONSIN52025
CathroMICHIGAN42016
CromwellMINNESOTA32025
Sherry LakeMINNESOTA32022
LudeMINNESOTA32025
MahtowaMINNESOTA32023
WausaukeeWISCONSIN32023
BashawWISCONSIN32025
BerglandMICHIGAN22011
Bear LakeMICHIGAN22025

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.