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

Bald Eagle In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionBirds of prey

Bald Eagle in Boreal Hardwood Transition has surged: up 848% on the route-weighted index since 1977.

+848%Since 1977TrendPercent 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 →
90Routes 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 →
48YearsYears 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 Bald Eagle in Boreal Hardwood Transition. See the full index history below.

Bald Eagle In Boreal Hardwood Transition Population Forecast

If the recent trend holds, Bald Eagle in Boreal Hardwood Transition is projected to stay roughly flat through 2030, near 0.32 (95% range 0.25–0.40). A 5-year backtest shows a typical error of ±20.2%, with 80% of held-out values landing inside the 95% band.

+8%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 →
0.32Projected 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 →
0.25–0.4095% 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 →
±20.2%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, Bald Eagle in Boreal Hardwood Transition is projected to stay roughly flat through 2030, near 0.32 (95% range 0.25–0.40). A 5-year backtest shows a typical error of ±20.2%, with 80% of held-out values landing inside the 95% band.19742030
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 →
20260.300.230.38
20270.310.230.38
20280.310.240.39
20290.320.240.39
20300.320.250.40

Routes In Boreal Hardwood Transition

Routes recording Bald Eagle 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 →
ExelandWISCONSIN52025
Wigwam BayMINNESOTA32023
BabbittMINNESOTA32016
Tamarac NwrMINNESOTA32023
IrmaWISCONSIN32025
RhinelanderWISCONSIN32021
Lake CityMICHIGAN22010
SkeelsMICHIGAN22007
OberlinMICHIGAN22024
CathroMICHIGAN22012
Pleasant Valley 2MICHIGAN22025
MayfieldMICHIGAN22025
Seney NwrMICHIGAN22010
CromwellMINNESOTA22024
Pine RiverMINNESOTA22024
LudeMINNESOTA22022
BrainerdMINNESOTA22024
BlackduckMINNESOTA22022
GlendaleMINNESOTA22022
WarroadMINNESOTA22024
GreenbushMINNESOTA22021
Nett LakeMINNESOTA22021
GilmanWISCONSIN22024
WausaukeeWISCONSIN22013
Land O' Lakes 2WISCONSIN22025

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