According to Marks et al. (1999), this family of predatory birds is plage
with a considerable confusion
regarding its constituent species, and even generic limits.This confusion is largely owed to similarities in plumage and
morphology, coupled with the lack of basic information on behaviour. In fact, the taxonomy of the Strigidae is in far
greater turmoil than that of any other family of non-passerine birds. This problem is especially compounded in the
genus Otus whose members inhabit tropical forests where fieldwork is extremely difficult.