Great Horned Owl - Description

Description

Great Horned Owls are the heaviest extant owl in Central and South America and are the second heaviest owl in North America, after the closely related but very different looking Snowy Owl (B. scandiacus). They range in length from 43–64 cm (17–25 in) and have a wingspan of 91–153 cm (36–60 in). Females are invariably somewhat larger than males. An average adult is around 55 cm (22 in) long with a 124 cm (49 in) wingspan and weighing about 1.4 kg (3.1 lb). Depending on subspecies, Great Horned Owls can weigh from 0.6 to 2.6 kg (1.3 to 5.7 lb). Among standard measurements, the tail measures 17.5–25 cm (6.9–9.8 in) long, the wing chord measures 31.3–40 cm (12.3–16 in), the tarsal length is 5.4–8 cm (2.1–3.1 in) and the bill is 3.3–5.2 cm (1.3–2.0 in).

There is considerable variation in plumage coloration but not in body shape. These are heavily built, barrel-shaped birds, and have large heads and broad wings. Adults have large ear tufts and are the only very large owl in their range to have them. The facial disc is reddish, brown or gray in color and there is a variable sized white patch on the throat. The iris is yellow, except the amber-eyed South American Great Horned Owl (B. V. nacurutu). Its "horns" are neither ears nor horns, simply tufts of feathers. The underparts are usually light with some brown barring; the upper parts are generally mottled brown. Most subspecies are barred along the sides as well. The legs and feet are covered in feathers up to the talons, with some black skin peaking out from around the talons. The feet and talons are distinctly large and powerful and only other Bubo owls have comparable formidable feet. There are individual and regional variations in color; birds from the sub-Arctic are a washed-out, light-buff color, while those from Central America can be a dark chocolate brown.

Their call is a low-pitched but loud ho-ho-hoo hoo hoo; sometimes it is only four syllables instead of five. The female's call is higher and rises in pitch at the end of the call. Young owls still in the care of their parents make loud, persistent hissing or screeching sounds that are often confused with the calls of Barn Owls (Tyto alba).

The combination of the species bulk, prominent ear-tufts and barred plumage distinguishes it through much of the range. However, Great Horned Owls can be easily confused with the Magellanic Horned Owl (B. magellanicus), with which they may have limited overlap in southermost South America. The Magellanic was once considered a subspecies of the Great Horned, but is markedly smaller with smaller feet and a smaller head and is generally more lightly barred on the underside. Other eagle-owls may superficially be somewhat similar, but the species is allopatric with the exception of the Magellanic species. In North America, the Long-eared Owl (Asio otus) can be somewhat similarly marked and shares the feature of prominent ear tufts, but it is considerably smaller and more slender, with a grayish line running down the middle of the facial disc and with ear tufts located more closely to each other on the top of the head.