The collage below shows Stygian Owls (Asio stygius) from Sinaloa, Mexico (top left, top centre), Cuba (top right), São Paulo state Brazil (bottom left) and Quito, Ecuador (bottom centre and bottom right). This shows shows some of the variation in three of the six subspecies: the nominate subspecies in the bottom row (although some have argued that the southern Brazilian birds should be in the A. s. barberoi subspecies) is described in most literature, the A. s. lambi subspecies from western Mexican is said to be a little paler, and the A. s. siguapa subspecies from Cuba apparently smaller with whiter markings. You can judge for yourself from these photos.
With their dark, almost black, plumage and long,
close-set ear-tufts (that look like horns), the Stygian Owl is arguably
the most “diabolical” of owls. The Stygian Owl (Asio stygius), is named
after the River Styx, which of course in Greek mythology was the gateway
to the afterlife. Indeed, in part because of their nocturnal haunts and
human-like faces, owls have a symbolism of death and/or the afterlife
in many cultures from all around the world; but the Stygian Owl arguably
best demonstrates that imagery. As with other owl species from around
the world, this species faces persecution in areas where it is believed
to be a witch or an evil spirit and the population on the island of
Hispaniola (A. s. noctipetens) is considered vulnerable for that reason.
Despite persecution based on fear, this is surely one of the most
handsome little devils anyone could encounter on a dark night!
The Stygian Owl is a member of the genus Asio, related to the
Long-eared Owl and Short-eared Owl that many of my North American, Asian
and European friends will be familiar with. The Stygian Owl is a couple
of inches larger than either of those two species but you can certainly
see the resemblance; for example, note the close-set ear-tufts as
opposed to the widely parted, sometimes sideways ear-tufts of Bubo
(“eagle-owls” and “horned owls”). The Stygian Owl has a deep hooting
call similar to Long-eared Owl except that the notes have a hint of a
disyllabic slur and slide down the scale a little. Although thought to
be mostly resident, there may be some nomadism or short migratory
movements since there are at least two winter records in southern U.S.A.