NC State Extension Publications

Introduction

Owls are birds of prey that primarily are active during the night and during twilight hours. Often mysterious to man, owls figure largely in myths, folklore and superstition. Much like hawks, owls prey on rodents, reptiles and other small animals, including invertebrates. Specific prey include crayfish, mice, snakes, lizards, birds, rabbits, and the occasional fish. Typically solitary feeders, owls may occasionally gather in winter roosts or at an abundant food source.

Owl Adaptations

  • Large retinas - Vision is 50-100 times better than humans in poor light
  • Many rods - High concentrations of rods in eyes (light-gathering cells)
  • Binocular vision - Fixed eyes view the same scene from slightly different angles - improving depth perception
  • Large head with wide ear spacing - Disk-like design receives sound at minute thresholds; large ear openings and asymmetric ear positions improve hearing
  • Stealth feathers - Leading wing feathers have soft-serrated edges for noiseless flight
  • Regurgitation - Owls absorb nutritious foods through stomach walls but regurgitate “pellets” of indigestible hairs, feathers, bones, and claws

Habitat

Owls are found across North Carolina. Owls are largely forest birds with most requiring cavities in dead or hollow trees or dense vegetation to seek refuge during the day. Habitat requirements vary among owl species, so it is important to consider the food and cover requirements of each species when developing a habitat management plan.


Common owl species.
Great-Horned Owl Barn Owl Barred Owl Screech Owl
Habitat
Open forests, fallow fields, and shrubland; Benefits from openings and clearings.
Nests in old crow, heron, or hawk nests.
Abandoned fields, pastures, and marsh areas; Benefits from openings and nest boxes.
Nests in man-made structures: silos, barns, and buildings.
Mature hardwood floodplain forests; Benefits from long hardwood rotations and snag retention.
Nests in hollow trees, often over water.
Forest, often densely stocked;
Nests in hollow trees, abandoned woodpecker cavities.
Food
Rabbits, woodrats, mice, grouse, squirrels, and other birds Voles, rats, and mice Snakes, frogs, turtles, small mammals, and occasional birds Mice, snakes, frogs, insects, flying squirrels, chipmunks, and small birds
Description
length: 20 - 23 inches
wingspan: 60 inches
weight: 3.5 pounds
length: 15 - 20 inches
wingspan: 44 inches
weight: 20 - 24 ounces
length: 20 inches
wingspan: 44 inches
weight: 2 pounds
length: 10 inches
wingspan: 22 inches
weight: 6 - 7 ounces
Prominent ear tufts; brown plumage above, mottled with grayish white; light gray underside with dark bars; a white band of feathers on the upper breast; rust colored face Long-legged, light color with a heart-shaped face; (also known as “monkey-faced” owl) white or pale cinnamon belly with buff or rusty upper feathers Rounded head, brown eyes; lacks ear tufts; gray-brown plumage with white spots on the back; whitish or grayish underparts barred with buff or deep brown Small owl with ear tufts; it exhibits two color phases: gray and red; chestnut red during red phase, brownish-gray during gray phase; pale breast and belly are streaked with dark gray or chestnut

Photo of barn owl.

Barn owl.

Thomas G. Barnes, USFWS

Photo of barred owl.

Barred owl.

Mark Musselman, National Audubon Society

Photo of great-horned owls in nest

Great-horned owls in nest.

USFWS

Owl Management

General

  • Create a diversity of stand ages intermixed with openings.
  • Create and maintain early successional vegetation using prescribed fire, herbicides, disking, and to a lesser extent bush hogging.
  • Maintain larger tracts of forest. Most species of owl use forests for roosting, nesting, and foraging.
  • Maintain and create snags in large diameter trees, typically at least 10“ in diameter at chest height.
  • Manage bottomland hardwoods in large blocks and long harvest rotations of at least 80 years.

Direct Improvements

  • Erect nest boxes for cavity-nesting owl species (Figure 1). Detailed plans for building owl nesting boxes can be found from the Cornell Ornithology Lab’s All About Birdhouses.
  • Construct brush piles to attract the rodents that owls eat.
  • Thin forest to promote development of understory plants, which in turn provide habitat for many prey species eaten by owls.

Owl box dimensions.
Species Cavity Floor* (inches) Cavity Side (inches) Entrance Above Floor (inches) Entrance Hole Size (inches)
Barn owl 11 x 2234 1238 x 16 4 334 x 412
Screech owl 10 x 1134 10 x 16 1112 3
Barred owl 1112 x 13 13 x 23 12 7
* add 2 inches to floor dimension for roof

Figure 1. Owl box construction.

Figure 1. Owl box construction.

Authors

Extension Professor
Forestry & Environmental Resources
Wildlife Biologist
Associate Professor and Extension Specialist (Wildlife)
Forestry & Environmental Resources

Publication date: Jan. 1, 2019
Revised: April 23, 2019

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North Carolina State University and North Carolina A&T State University commit themselves to positive action to secure equal opportunity regardless of race, color, creed, national origin, religion, sex, age, veteran status or disability. In addition, the two Universities welcome all persons without regard to sexual orientation.