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

Song Sparrow In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionForest birds

Song Sparrow in Boreal Hardwood Transition has declined: down 37% on the route-weighted index since 1968.

-37%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 →
127Routes 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 Song Sparrow in Boreal Hardwood Transition. See the full index history below.

Song Sparrow In Boreal Hardwood Transition Population Forecast

If the recent trend holds, Song Sparrow in Boreal Hardwood Transition is projected to stay roughly flat through 2030, near 14 (95% range 8.0–20). A 5-year backtest shows a typical error of ±30.1%, with 80% of held-out values landing inside the 95% band.

-7%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 →
14Projected 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 →
8.0–2095% 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 →
±30.1%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, Song Sparrow in Boreal Hardwood Transition is projected to stay roughly flat through 2030, near 14 (95% range 8.0–20). A 5-year backtest shows a typical error of ±30.1%, with 80% 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 →
2026158.721
2027158.521
2028158.421
2029148.221
2030148.020

Routes In Boreal Hardwood Transition

Routes recording Song 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 →
GilmanWISCONSIN562025
BagleyMINNESOTA502006
Amnicon FallsWISCONSIN472025
PickfordMICHIGAN442025
BayfieldWISCONSIN402025
Weirgor SpringsWISCONSIN392025
Hart LakeMINNESOTA382025
RiggsvilleMICHIGAN362019
Pleasant Valley 2MICHIGAN362025
FloodwoodMINNESOTA342025
MayfieldMICHIGAN322025
LudeMINNESOTA322025
GreenbushMINNESOTA322025
OntonagonMICHIGAN312019
Maple GroveMICHIGAN312025
MahtowaMINNESOTA302023
BrainerdMINNESOTA302024
Wigwam BayMINNESOTA292023
DebsMINNESOTA282025
Nett LakeMINNESOTA282024
Iron RiverWISCONSIN272025
Little ForkMINNESOTA262024
BashawWISCONSIN262025
NebishMINNESOTA252025
HermanMICHIGAN242022

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