BirdAnalyst
Species · BBS 2026 Release · 1966–2025

Great Horned Owl Population Analysis

StrigidaeBirds of preyBubo virginianus

Great Horned Owl has risen sharply: up 54% on the route-weighted index since 1968.

+54%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 →
2,746RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
59Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Great Horned Owl

The Great Horned Owl (Bubo virginianus) is a North American member of the Owls (Strigidae). In this analysis it is grouped with the birds of prey.

Size
5–27.5 in long (13–70 cm) — a nocturnal raptor (typical for the family)
Habitat
Open country, woodlands, cliffs and wetlands, hunting from the air or a high perch.
Diet
Live prey — small mammals, birds, reptiles, fish and large insects (carrion for vultures).
Range
Recorded on 2,746 Breeding Bird Survey routes across 49 states, most concentrated in the Eastern Tallgrass Prairie.
Family
Strigidae · Birds of prey

Notable Great Horned Owl TrendsNotable 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 increasecomputed 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 risen sharply in surveyed states: up 54% on the route-weighted index since 1968.

Great Horned Owl Population Forecast

If the recent trend holds, Great Horned Owl is projected to rise about 20% by 2030 — from 0.14 in 2025 to a central estimate of 0.16 (95% range 0.08–0.25). A 5-year backtest shows a typical error of ±30.5%, with 100% of held-out values landing inside the 95% band.

+20%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 →
0.16Projected 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 →
0.08–0.2595% 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 →
±30.5%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 is projected to rise about 20% by 2030 — from 0.14 in 2025 to a central estimate of 0.16 (95% range 0.08–0.25). A 5-year backtest shows a typical error of ±30.5%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20260.170.080.25
20270.170.080.25
20280.170.080.25
20290.170.080.25
20300.160.080.25

Where the Great Horned Owl Is Detected

BBS routes recording Great Horned Owl, sized by most recent count.

Great Horned Owl Population Trend by State

Great Horned Owl population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Alabama+89%196865
Alaska-61%198354
Arizona+7%197062
Arkansas-52%197137
California+209%1971177
Colorado-59%1970117
Connecticut+61%198114
Delaware+88%196910
Florida+134%196977
Georgia+29%197168
Idaho-55%197141
Illinois+10%197089
Indiana-54%197341
Iowa-42%196936
Kansas-6%196963
Kentucky-26%197039
Louisiana+25%196951
Maine-32%198018
Maryland-46%196855
Massachusetts+32%199111
Michigan-49%197343
Minnesota-58%197072
Mississippi+7%197336
Missouri-42%196975
Montana-24%197074
Nebraska+4%196964
Nevada+31%197420
New Hampshire-9%19799
New Jersey+91%198124
New Mexico+11%197055
New York-20%196869
North Carolina+35%197864
North Dakota-8%197049
Ohio+100%196856
Oklahoma+136%196965
Oregon-61%197099
Pennsylvania-16%196896
Rhode Islandinsufficient datan/a1
South Carolina+0%197129
South Dakota-81%196957
Tennessee+193%197438
Texas-33%1969181
Utah-47%197047
Vermontinsufficient datan/a5
Virginia-33%197057
Washington-75%197361
West Virginia+18%198222
Wisconsin-35%196975
Wyoming-91%197078

Great Horned Owl Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Great Horned Owl population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
BCR 4-57%198345
Northern Pacific Rainforest-22%197067
Great Basin+22%1971161
Northern Rockies-74%1970131
Prairie Potholes-67%1969114
Boreal Hardwood Transition-59%196956
Lower Great Lakes / St. Lawrence Plain-2%196856
Atlantic Northern Forest+14%197638
Sierra Nevada-41%197324
Southern Rockies / Colorado Plateau-51%1970120
Badlands and Prairies-83%1969103
Shortgrass Prairie-16%1970110
Central Mixed Grass Prairie+29%1969119
Edwards Plateau-80%197017
Oaks and Prairies+10%196963
Eastern Tallgrass Prairie-29%1968221
Prairie Hardwood Transition+171%1968120
Central Hardwoods+9%1970117
West Gulf Coastal Plain / Ouachitas-55%197055
Mississippi Alluvial Valley+86%196948
Southeastern Coastal Plain+517%1968215
Appalachian Mountains+41%1968217
Piedmont-40%1968106
New England / Mid-Atlantic Coast-7%196898
Peninsular Florida+33%196949
Coastal California+184%197296
Sonoran and Mojave Deserts+24%197247
Sierra Madre Occidental-3%197031
Chihuahuan Desert-33%197044
Tamaulipan Brushlands-51%196923
Gulf Coastal Prairie+145%198130

Great Horned Owl Conservation Status

Our route-weighted index shows it up about 54% since 1968.

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14. Trend is a route-weighted relative-abundance index, not an absolute population.