This owl grows to 20 to 25 inches and prefers to live in forests, woodlots, deserts or residential areas. Among the owls that live in Canada and the United States, the great horned owl has the largest eyes. Its eyes are equal in size to those of an adult human, who would weigh at least 50 times more than the owl. Great horned owls are adaptable birds and live from the Arctic to South America.

Great horned owls predominantly occur throughout the North American tree line and its habitat includes woodlands, agricultural areas, tropical rainforests, mountainous areas, mangrove swamp forests, rocky coasts, saltwater marshes, freshwater marshes, mesquite, semi-arid grasslands, cacti deserts, deciduous, mixed and coniferous forests. They are at home in suburbia as well as in woods and farmlands. The eye of a great horned owl is so large, the entire skull of a house sparrow can fit inside it. The Great Horned Owl Great horned owls like to take over abandoned nests of crows, great blue herons and hawks but, like other owls, sometimes make nests in cavities.