Great Horned Owl Biology

A Reference for North and Central American Owls

Name: Great Horned Owl - Bubo virginianus
Other Common Names: Virginia Horned Owl (virginianus); Dusky Great Horned Owl (saturatus); Montana Great Horned Owl (occidentalis); Northwestern Great Horned Owl (lagophonus); Labrador Great Horned Owl (heterocnemis); St. Michael Great Horned Owl (algistus); Western Great Horned Owl (pallescens) Pacific Great Horned Owl (pacificus); Tundra Great Horned Owl (subarticus); hoot owl; chicken owl; eagle owl; king owl.

Subspecies: Strictly speaking the Great Horned Owl is only found in the Americas. It has sometimes been considered to be part of the Eurasian Eagle-Owl (Bubo bubo) species that is spread across Eurasia. There are currently 8 recognized races of Great Horned Owl in North America. There are 4 races that have been described but further study will be required. There are also 2 races in Central America and 2 in South America (a third was recently divided into its own species).
B. v. lagophonus is found from Alaska south in the mountains to N. E. Oregon and as far east as W. Montana. The described race algistus is included here although both northern populations of races lagophonus and N. E. Canada's heterocnemis race may not be separable with the western race saturatus.
B. v. saturatus is found along the pacific coast from S. E. Alaska to N. California.
B. v. pacificus is found along the California coastline (except far north) and as far south as N. Baja California.
B. v. subarticus is found from E. British Columbia east to the Hudson Bay and south to at least the Northern U. S. The described race occidentalis of the Rocky Mountains has been included here. A mix with lagophonus or pallescens (or an unnamed race) may inhabit south to Arizona.
B. v. pallescens is found from C. and S. E. California east to W. Kansas and south to C. Mexico.
B. v. heterocnemis is found in N. E. Canada south to the Great Lakes. The described race scalariventris of Ontario and E. Manitoba has been included here.
B. v. virginianus is found from Minnesota south to E. Texas and east to the Atlantic from Prince Edward Island to Florida.
B. v. elachistus is found in Baja California.
B. v. mayensis is found on the Yucatan Peninsula.

Measurements and Weights:
Wingspan: 50 - 60 in.
Length: 18 - 25 in.
Tail: 6.9 - 9.9 in.
Average Weight: Male: 46 1/2 oz.
Average Weight: Female: 61 oz.

  • Great Horned Owl

Description: The Great Horned Owl is a large, powerful, and mostly nocturnal owl. It is also the only large owl with ear tufts. The smaller, medium sized Long-Eared Owl is similar in appearance although can be distinguished by its smaller size, slimmer shape, longer ear tufts, cross barred under parts, and different call (the Great Horned has a distinctive advertising hoot that 'might' only be confused with a Great Gray Owl). The Great Horned Owl is very widespread and common but can vary in color dramatically between regions although its markings do remain reasonably constant and it always has prominent ear tufts. Its under parts have thin dark brown bars on a whitish base with the upper chest bars becoming somewhat blotchy. The throat has a bold white patch; white mustache and white to tan along the sides of the bill into the eyebrows. The prominent facial disk is bordered at the sides with black. The eyes are from lemon yellow to straw colored with a thin black border. The backside has fine dark mottling with dark bars on the primaries and tail. The races tend to get smaller in size from the northeast to the southwest. The races also tend to blend with their habitat in their coloration. The owl varies in overall and facial disk color from whitish to orange-buff to brownish-gray to dark brown. The northern members of the subarticus race being the lightest with a whitish facial disk and overall whitish-buff base color. The darkest race being the saturatus with a deep brown facial disk, chest, and base color to its backside.

Young: The young are similar in coloration with the adults although their barring and dark markings are not as crisp and defined, ear tufts smaller or not apparent. It also has a screech similar to a barn owl for a call.