BirdAnalyst
Species · Wyoming · BBS 2025 Release · 1966–2024

Great Horned Owl Population Trend in Wyoming

All statesGeneralists

Great Horned Owl in Wyoming has collapsed: down 90% on the route-weighted index since 1970.

-90%Since 1970TrendPercent 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 →
78Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
54YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Great Horned Owl Trends in WyomingNotable 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 collapsed in Wyoming: down 90% on the route-weighted index since 1970.

Great Horned Owl Population Forecast in Wyoming

If the recent trend holds, Great Horned Owl in Wyoming is projected to fall about 100% by 2029 — from 0.07 in 2024 to a central estimate of 0.00 (95% range 0.00–0.29). A 5-year backtest shows a typical error of ±168.4%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–0.2995% 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 →
±168.4%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, Great Horned Owl in Wyoming is projected to fall about 100% by 2029 — from 0.07 in 2024 to a central estimate of 0.00 (95% range 0.00–0.29). A 5-year backtest shows a typical error of ±168.4%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20250.000.000.29
20260.000.000.29
20270.000.000.29
20280.000.000.29
20290.000.000.29

Great Horned Owl Survey Routes in Wyoming

Routes recording Great Horned Owl in Wyoming.
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 →
Dwyer919921992
Upton420241992
Worland320122012
Harmony320171987
Midvale220221975
Mckinnon219801977
Bald Mtn220021991
Mayoworth220101983
Seedskadee220161993
Ne Entrance120122012
Cody120061991
Otto120141971
Basin120172017
Wyarno120061974
Clarkelen119711971
Sundance120151975
Dubois120131984
Natrona119911970
Bill119931974
Redbird119821968
Fontenelle119981995
Elk Horn120021999
Bear Creek120192019
Ervay120162016
Brookhurst120151968

Great Horned Owl Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsin

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