BirdAnalyst
Species · BCR 12 · BBS 2025 Release · 1966–2024

Clay-colored Sparrow In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionGeneralists

Clay-colored Sparrow in Boreal Hardwood Transition has declined: down 33% on the route-weighted index since 1968.

-33%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 →
104Routes 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 →
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 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 53% by 2029 — from 2.1 in 2024 to a central estimate of 3.2 (95% range 1.8–4.5). A 5-year backtest shows a typical error of ±72.2%, with 20% of held-out values landing inside the 95% band.

+53%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 →
3.2Projected 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 →
1.8–4.595% 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 →
±72.2%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 53% by 2029 — from 2.1 in 2024 to a central estimate of 3.2 (95% range 1.8–4.5). A 5-year backtest shows a typical error of ±72.2%, 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 →
20253.21.84.6
20263.21.84.6
20273.21.84.5
20283.21.84.5
20293.21.84.5

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
GreenbushMINNESOTA242024
DebsMINNESOTA182024
Iron RiverWISCONSIN152024
PickfordMICHIGAN142024
WarroadMINNESOTA112024
Little ForkMINNESOTA92024
BrainerdMINNESOTA82024
BayfieldWISCONSIN82024
Pine RiverMINNESOTA72024
Amnicon FallsWISCONSIN72024
HerronMICHIGAN62016
LudeMINNESOTA62023
Nett LakeMINNESOTA62024
WilsonMICHIGAN52010
BackusMINNESOTA52024
McgregorMINNESOTA52024
CathroMICHIGAN42016
Union TwpWISCONSIN42024
CromwellMINNESOTA32023
Sherry LakeMINNESOTA32022
WaskishMINNESOTA32024
MahtowaMINNESOTA32023
MinongWISCONSIN32023
WausaukeeWISCONSIN32023

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