The Hispaniolan Barn owl

The Hispaniolan Barn Owl, scientifically known as Tyto glaucops, was a species endemic to the island of Hispaniola.

Description

Although closely related in morphology and coloration to the Common Barn Owl, the Hispaniolan Barn Owl displayed distinctive features that set it apart. Its ash-grey facial disc, encircled by a reddish-brown ring, was one of its most striking traits. The plumage also exhibited a remarkable variety of patterns: the yellowish-brown underparts were finely marked with dark vermiculations, while the wings were speckled with tawny and buff shades.

Notable differences exist between populations. For instance, the subspecies insularis, found primarily in the Lesser Antilles, displays a vinaceous-brown facial disc and underparts shaded towards cinnamon-buff. The race nigriscens, by contrast, is slightly less mottled, though it shows a similar greyish upper plumage.

These nocturnal birds, which occur in different forms (pale, dark, or intermediate), nevertheless maintain consistency in size and morphology between the sexes, although females are generally larger and heavier than males.

“The Hispaniolan Barn Owls produce a kind of hissing sound, preceded by a series of higher-pitched clicks. In Hispaniola, a piercing ‘criiiisssssssssssh’ lasting two to three seconds can also be heard. On Dominica, both a far-carrying scream and a clicking call have been recorded. Other vocalizations resemble those of the Common Barn Owl. In the rest of the Lesser Antilles, the repertoire of calls remains undocumented.” — Oiseaux.net

Habitat

The Hispaniolan Barn Owl (Tyto glaucops) occupies a wide range of habitats, from open woodlands to dense forests, as well as scrublands, caves, cultivated fields, abandoned buildings, and occasionally even villages and the outskirts of towns. They are found at elevations ranging from sea level up to about 2,000 meters. On the island of Hispaniola, these owls generally favor denser wooded areas than those typically frequented by the Common Barn Owl (Tyto alba) on other islands.

Following a recent taxonomic reassessment, this species is no longer regarded as strictly endemic to Hispaniola. It is also present in Puerto Rico and in the smaller islands of the eastern Caribbean. At present, four subspecies are recognized:

T. g. glaucops – Occurs on Hispaniola, including Tortuga Island.
T. g. cavatica – Restricted to Puerto Rico.
T. g. nigrescens – Found on Dominica, in the north-central Lesser Antilles.
T. g. insularis – Inhabits Saint Vincent, Bequia, Union, Carriacou, and Grenada in the southern Lesser Antilles.

These subspecies can be distinguished by subtle differences in plumage and habitat preference, although they all share similar ecological traits and modes of life.

Diet and Reproduction

In Dominica, clutches of the Hispaniolan Barn Owl are observed in September, with chicks appearing in April. On Hispaniola itself, the peak breeding season occurs between January and June. These owls prefer to nest in natural cavities such as caves, but they also make use of tree hollows, branches, sinkholes, and cliff ledges. Artificial sites, such as lofts, similar to those used by the Common Barn Owl, are likewise considered suitable.

Clutches typically contain between three and seven white eggs, although details regarding the duration of incubation and nestling period remain unknown.

The diet of the Hispaniolan Barn Owl is diverse, consisting primarily of small rodents such as rats and mice, as well as bats. They also consume a wide variety of bird species, ranging from doves and parakeets to hummingbirds and trogons. Reptiles such as iguanas, along with snakes, tree frogs, and other amphibians, are also taken. Insects and spiders complement their diet.

A recent study of regurgitated pellets revealed that introduced small mammals account for up to 76% of the biomass consumed. Bats of the genera Mormoops and Noctilio are also significant prey items. Although the Hispaniolan Barn Owl consumes a higher proportion of birds than the Common Barn Owl, the two species share as many as 92 prey species in common.