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

Black-billed Cuckoo In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionGeneralists

Black-billed Cuckoo in Boreal Hardwood Transition has edged down: down 21% on the route-weighted index since 1968.

-21%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 →
125Routes 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 Black-billed Cuckoo in Boreal Hardwood Transition. See the full index history below.

Black-billed Cuckoo In Boreal Hardwood Transition Population Forecast

If the recent trend holds, Black-billed Cuckoo in Boreal Hardwood Transition is projected to stay roughly flat through 2029, near 0.83 (95% range 0.00–2.5). A 5-year backtest shows a typical error of ±47.4%, with 100% 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 →
0.83Projected 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 →
0.00–2.595% 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 →
±47.4%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, Black-billed Cuckoo in Boreal Hardwood Transition is projected to stay roughly flat through 2029, near 0.83 (95% range 0.00–2.5). A 5-year backtest shows a typical error of ±47.4%, with 100% 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 →
20250.920.002.6
20260.900.002.6
20270.880.002.5
20280.860.002.5
20290.830.002.5

Routes In Boreal Hardwood Transition

Routes recording Black-billed Cuckoo 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 →
Iron RiverWISCONSIN222024
CreightonMICHIGAN112021
ChaffeyWISCONSIN112022
LudeMINNESOTA92023
WarroadMINNESOTA92023
MuskallongeMICHIGAN82019
CunardMICHIGAN72021
Hubbard LakeMICHIGAN71994
GilmanWISCONSIN72023
Beaver LakeMICHIGAN51994
Frederic 2MICHIGAN52015
WaskishMINNESOTA52023
BootjackMICHIGAN42023
ShingletonMICHIGAN42022
FredericMICHIGAN42003
GreenbushMINNESOTA42024
ChisholmMINNESOTA42023
Ned LakeMICHIGAN32024
Lake CityMICHIGAN32009
PickfordMICHIGAN32017
CathroMICHIGAN32011
Sand LakeMICHIGAN32022
BackusMINNESOTA32022
Pine RiverMINNESOTA32022
HovlandMINNESOTA32021

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