BirdAnalyst
Species · BCR 9 · BBS 2025 Release · 1966–2024

Great Horned Owl In Great Basin

All regionsGreat BasinGeneralists

Great Horned Owl in Great Basin has increased: up 34% on the route-weighted index since 1971.

+34%Since 1971TrendPercent 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 →
160Routes 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 →
55YearsYears 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 Great Horned Owl in Great Basin. See the full index history below.

Forecast

If the recent trend holds, Great Horned Owl in Great Basin is projected to stay roughly flat through 2029, near 0.17 (95% range 0.04–0.30). A 5-year backtest shows a typical error of ±26.8%, with 100% of held-out values landing inside the 95% band.

-6%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 →
0.17Projected 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 →
0.04–0.3095% 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 →
±26.8%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, Great Horned Owl in Great Basin is projected to stay roughly flat through 2029, near 0.17 (95% range 0.04–0.30). A 5-year backtest shows a typical error of ±26.8%, with 100% of held-out values landing inside the 95% band.19692029
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 →
20250.170.040.30
20260.170.040.30
20270.170.040.30
20280.170.040.30
20290.170.040.30

Routes In Great Basin

Routes recording Great Horned Owl in Great Basin.
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 →
EwanWASHINGTON72012
Mud LakeIDAHO52023
BatesIDAHO52018
DorrisCALIFORNIA42019
Grouse CreekUTAH41997
MacdoelCALIFORNIA32019
BridgeportCALIFORNIA31976
GiffordIDAHO31991
SquirrelIDAHO31994
Blackft ResIDAHO31988
AlmoIDAHO32015
MontagueOREGON32024
Modoc Point 2OREGON32024
SnowdenWASHINGTON31972
PomeroyWASHINGTON32024
Big PineCALIFORNIA21992
BodieCALIFORNIA22013
Crowder FlatCALIFORNIA22019
BakerIDAHO22004
MoraIDAHO22022
PicaboIDAHO22021
Gardnerville 2NEVADA22015
Ruby Valley 2NEVADA22021
Lone RockOREGON22024
JosephOREGON21973

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