The Barn Owl

The Barn Owl (Tyto alba) was introduced to Hawaii in April, June and October 1958 to control rodents. A total of 15 birds were imported from California by the state Department of Agriculture and released at Kukuihaele on Hawaii Island. Over the next five years, an additional 71 owls were introduced on Kauai, Oahu, and Molokai on Molokai Ranch lands. Nowadays the barn owl is found throughout the main Hawaiian Islands, including offshore islets such as Lehua near Kaua‘i.

​

They have light grey underparts with numerous fine dark lines and scattered pale spots on the feathers. There are buff markings on wings and back. Feathering on the lower legs may be sparse. The heart-shaped facial disc is white with a brownish edge, with brown marks at the front of the eyes, which have a black iris. Its beak is off-white and the feet are yellowish-white to brownish. Males and females are similar in size and color; females and juveniles are generally more densely spotted. Barn owls can be distinguished from pueo by their primarily nocturnal habits, rounder faces, and lighter colouring.

Though considered a rodent specialist throughout continental North America, barn owls in Hawaii have been documented preying upon multiple avian species and may pose a significant threat to nocturnally active seabirds. Seabird predation by barn owls has been documented on offshore islets, the coast of the main islands, and in montane forests where they are known predators of endangered Hawaiian petrels (Pterodroma sandwichensis) and threatened Newell's shearwaters (Puffinus auricularis newelli). Seabird mortality due to barn owl predation has been repeatedly documented on Maui Island on wedge-tailed shearwaters (Puffinus pacificus), on Lānai on Hawaiian petrels, and on Oahu's offshore islets on Bulwer's petrels (Bulweria bulwerii). Loss of adult petrels to owls is significant. Predation on breeding adults leads to reduced breeding success, and owl predation at all life stages prevents successful implementation of planned recovery actions for the species.

​