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

Great Horned Owl In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionGeneralists

Great Horned Owl in Boreal Hardwood Transition has fallen sharply: down 59% on the route-weighted index since 1969.

-59%Since 1969TrendPercent 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 →
56Routes 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 →
49YearsYears 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 →

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Great Horned Owl has fallen sharply in Boreal Hardwood Transition: down 59% on the route-weighted index since 1969.

Forecast

If the recent trend holds, Great Horned Owl in Boreal Hardwood Transition is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.08). A 5-year backtest shows a typical error of ±145%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.02Projected 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 →
0.00–0.0895% 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 →
±145%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, Great Horned Owl in Boreal Hardwood Transition is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.08). A 5-year backtest shows a typical error of ±145%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.030.000.09
20260.020.000.09
20270.020.000.08
20280.020.000.08
20290.020.000.08

Routes In Boreal Hardwood Transition

Routes recording Great Horned Owl 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 →
Little ForkMINNESOTA52013
Bear LakeMICHIGAN22004
McgregorMINNESOTA21999
BrainerdMINNESOTA22014
Nett LakeMINNESOTA22021
Tamarac NwrMINNESOTA22004
PhillipsWISCONSIN22012
BashawWISCONSIN22005
BootjackMICHIGAN12006
Gibbs CityMICHIGAN12002
TahquamenonMICHIGAN11976
GilchristMICHIGAN11991
Skegemog PtMICHIGAN12003
RacoMICHIGAN12016
PickfordMICHIGAN12013
SkeelsMICHIGAN11978
FredericMICHIGAN12000
OberlinMICHIGAN12000
Sand LakeMICHIGAN11995
Seney NwrMICHIGAN12011
CromwellMINNESOTA12007
Wigwam BayMINNESOTA11995
Mille LacsMINNESOTA11998
BackusMINNESOTA12013
Pine RiverMINNESOTA11986

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