Document Type

Honors Project

First Advisor

Dr. Michael Hensley

Degree Award Date

Fall 2008


Analysis, Diet, Shenandoah Valley, Barn Owl


Animal Sciences | Poultry or Avian Science


The barn owl or the Tyto alba is a nocturnal bird of prey. Barn owls are an important creature in the balancing and control of pest and rodent populations. Often being identified by their appearance, the common barn owl has a white or tan underside, long wings colored in shades of black, brown, tan and white, and a distinct heart-shaped white facial disk. The unique features of the barn owl's face make them have excellent senses for hunting. The facial disk actually funnels the sound into the ear holes of the owl, which are located on either side of the face. The owl also can sense how far the prey object is away because of another unique feature, lopsided or uneven ear holes. Because of these features, the barn owl is well suited for its nocturnal hunting status.

The main diet of the barn owl is mostly small mammals. Studies have shown that voles seem to be the most prevalent food source for the owl , but other small rodents such as mice, shrews, and moles are also consumed. Studies also show that over ninety-five percent of the diet of the barn owl consists of these small mammals . Other non-mammalian prey consisting of birds, amphibians, reptiles, and large insects is also eaten. However, the diet of the owls will depend greatly on the population of the rodents in the area. Because of the diet of the barn owl, they are useful in the natural management and control of many pest populations.

The prey of the barn owl is often swallowed whole. If they prey is too large to consume in this way it is torn into small pieces. After ingestion, the indigestible portions of the prey such as the bones, teeth, and fur are regurgitated in what we refer to as an "owl pellet". These pellets are often one to two inches in length and contain all of the indigestible portions of the owl's diet. In this way, the pellet makes a perfect tool for analysis. Because it contains the bones of the owl's prey, a diet analysis can be performed simply by analyzing the remains within the pellet. The primary diet of the owl can then be determined and statistical results can be drawn. These results can be compared to those from other geographical locations to see if there are deviations.