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

Eastern Bluebird In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionForest birds

Eastern Bluebird in Boreal Hardwood Transition has declined: down 46% on the route-weighted index since 1968.

-46%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 →
118Routes 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 Eastern Bluebird in Boreal Hardwood Transition. See the full index history below.

Forecast

If the recent trend holds, Eastern Bluebird in Boreal Hardwood Transition is projected to stay roughly flat through 2029, near 1.9 (95% range 0.42–3.3). A 5-year backtest shows a typical error of ±147.8%, with 80% of held-out values landing inside the 95% band.

-2%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 →
1.9Projected 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 →
0.42–3.395% 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 →
±147.8%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, Eastern Bluebird in Boreal Hardwood Transition is projected to stay roughly flat through 2029, near 1.9 (95% range 0.42–3.3). A 5-year backtest shows a typical error of ±147.8%, with 80% 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 →
20251.90.413.3
20261.90.413.3
20271.90.413.3
20281.90.413.3
20291.90.423.3

Routes In Boreal Hardwood Transition

Routes recording Eastern Bluebird 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 →
Betchler LksMICHIGAN112024
Union TwpWISCONSIN102024
Cedar RunMICHIGAN91999
Skegemog PtMICHIGAN82024
RiggsvilleMICHIGAN82019
CunardMICHIGAN72019
Pleasant ValMICHIGAN71997
Hiawatha NfMICHIGAN72024
BrainerdMINNESOTA72024
DebsMINNESOTA62024
CouderayWISCONSIN62019
Beaver LakeMICHIGAN52011
HarriettaMICHIGAN52024
Seney NwrMICHIGAN52024
Island LakeMINNESOTA51988
Nett LakeMINNESOTA52024
MinongWISCONSIN52024
GilmanWISCONSIN52024
Washington IWISCONSIN52024
MareniscoMICHIGAN42019
CathroMICHIGAN42016
Pleasant Valley 2MICHIGAN42024
Rib LakeWISCONSIN42024
OntonagonMICHIGAN32014
WilsonMICHIGAN32009

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