The first fossil specimen was mistakenly described as a bird in the family Phorusrhacidae, in part because the bones were so large. In 1961, Pierce Brodkorb reviewed the findings and placed them properly, with the owls. Remains have been abundant throughout the island, in cave deposits from the Late Pleistocene period (126,000 to 11,700 years ago) and at least three nearly complete skeletons have been found. These owls were primarily found in Cuba, their fossils were only ever found in the Cuban islands.