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EXTINCT ANIMALS
The remains of this bird were first discovered in Cueva de Pio Domingo in western Cuba, and it was thought, initially, that they belonged to a Cuban species of terror bird because of their size. The bones clearly belonged to a large bird that spent most of its time on the ground. In the early 1960s, a paleontologist was examining these bones, and he saw them for what they really were: the remains of a giant, extinct owl. Today around 220 owls species are recognized and zoologists separate them into two groups: the typical owls and the relatively longlegged and highly nocturnal barn owls. For most owls, the day begins when the sun goes down, when they leave their daytime retreats to hunt their prey. There can be few predators as beautifully adapted as the owls. Their senses of sight and hearing are acute, and their wing beat is muffled by the soft barbule tips on the leading edge of the flight feathers, which dampen air noise during flight. These adaptations allow them to find prey in low light levels and to make an approach without alerting the hapCuban Giant Owl—The ground-dwelling less victim. Cuban giant owl stood about 1 m high, Since the first bones of the giant owl came to dwarfing most modern owls. (Renata light, lots of remains have been found all over Cunha) Cuba, including three more or less complete skeletons. These bones indicate a large animal that was predominantly a ground dweller. Isolated on the island of Cuba, the giant owl deviated from the owl norm and took up life on the ground. Although there are owls today that spend a lot of time on the ground (e.g., the burrowing owl, Athene cunicularia), they still have large wings and powerful flight muscles and can take to the air with ease. Unlike some other ground-dwelling birds that have completely forsaken the power of flight, the sternum of the giant owl does have a keel, indicating that the living bird’s flight muscles may have been large enough to take the bird into the air for very short distances. Much like a turkey, the giant owl was probably capable of short, feeble flights when threatened, but its long legs and large feet suggest that it preferred stalking around at ground level. In terms of size, the giant owl was far in excess of any living owl. The two eagle owl species, (Bubo bubo and Bubo blakistoni), are the largest living owls and can reach a weight of around 4.5 kg. The Cuban owl was probably double this weight. Because of its size and because Cuba was free of large mammalian predators, the Cuban giant owl may have switched from a nocturnal lifestyle to a diurnal one. Strutting around the forested islands of Cuba, the giant owl used its predatory adaptations to hunt animals as large as hutia (Capromys pilorides), stocky Caribbean rodents and small capybara (Hydrochaeris hydrochaeris), the largest living rodents. Like other ground-dwelling birds, the Cuban giant was probably an accomplished runner, and it very likely ran its quarry down before dispatching it with its powerful talons and beak.