Species-Specific Management (SSM)

Screech Owl

The screech owl, Otus asio, is an adaptable bird inhabiting virtually all of the United States, sections of southern Canada, and parts of Mexico. The sub-species residing in Virginia is a mature forest/field edge dweller existing in two color phases, red and gray. The color phase seemingly depends upon the dominant tree species where it resides. Regardless of color phase, the screech owl is deserving of management efforts.

If you desire more screech owls in your area . . .

1. Protect existing snags! Snags are dead trees that remain, or partially remain, standing. The screech owl is a cavity nester. Snags excavated by woodpeckers, or other species, provide cavities for a variety of cavity nesting animals, including the screech owl. Snags are much better for wildlife than for firewood. Two per acre should suffice.
2. If no snags exist, you may want to create some. Cutting a two-inch wide strip of bark and removing it completely around a tree, insuring the cut penetrates the inner bark and cambium layer, will kill the tree and provide snags for the future. Caution! Be careful. Do not cut your valuable food-producing trees. (Other information is available.)
3. Screech owls will use nest boxes in the absence of natural snag cavities. A box constructed 10x10x14 inches with a 3 inch diameter hole nearer the top, and a perching peg below the hole on the exterior, will suit nesting screech owls.
4. Protect streamsides! Do not cut timber or allow livestock to graze within 25 meters (a little more than 25 yards) of either bank. Screech owls seem to prefer these areas. The owls' widely-variable diet includes crayfish, frogs, salamanders, toads, and minnows. Thus, there is the need for protecting streambanks.
5. Maintain or create edge areas. Edge occurs where two distinctly different cover types adjoin. Picture an area where mature forest (usually open woodland with many large diameter trees in excess of 80 to 100 years old) adjoins old field habitat. This is prime edge area. An ideal situation occurs where mature forest meets an area of low shrubs and briers which, in turn, adjoins an area of grassland. These areas generate abundant food and cover for small mammals and birds and, in turn, provide food for predators such as the screech owl. Secondly, these areas are rich in insects, a critical part of the owls' diet in spring and summer.
6. If the above areas already exist on your property, protect and maintain them. Do not allow livestock to graze all the way to the forest edge. Keep a 5-10 meter strip, next to the forest, in the 5-10 year age class (number of years post clearing). Maintain an adjoining section (5-10 meters) in a medium-to-tall grass stage (clover, lespedeza, etc.)
7. If these areas do not exist, you may wish to create them. If cutting a clearing into a woodland, it should be much longer than it is wide. This creases more edge per unit of cleared area. Think small! Openings need not exceed 5 acres. An enormous amount of edge can be created by "stretching" one acre. Picture one square acre. Now cut it into 5 strips, lay them end to end, and you get the idea. The desired age classes can be created by allowing succession to proceed to the desired level. Some planting of the grasses may be required.
8. Screech owls nest in the spring. Most eggs are laid between early and late April, and hatch three to four weeks later. During this time, the nests are vulnerable to predation by raccoon, opossum, or other predators. If you have identified a cavity that is being used by owls, you can protect it from ground-dwelling predators by placing a tin barrier 10 to 12 inches wide about 4 feet from the ground.
9. Concentrate your efforts in small areas with mature forests containing several snags near a stream and with some good edge area nearby, as this may be the optimum in screech owl living space.
10. The primary cause of screech owl mortality is collision with automobiles. Practice management away from frequently-travelled roadways.
11. The screech owl is not known to migrate very far. Only local migrations in response to a food supply shift occur.
12. There may be some migration in the extreme northern sections of the owls' range, but management techniques should work equally well in all of these areas.

Observing your owls will require some time outdoors at night. Screech owls are active from just past dusk until just prior to dawn. By using a low intensity amber or red beamed light, you can observe your owls as they enter and leave their nests. They will become accustomed to your presence, but do not approach too close: screech owls are aggressive nest defenders! Peak viewing opportunity will occur from mid-March until mid-May. During this period, the owls will be continually entering and leaving the nest to tend eggs or feed their young.

This may seem to be extensive work to promote a few screech owls, but remember, much of what you do will benefit many other species in your area. Grouse, quail, turkey, deer, songbirds, woodpeckers, small mammals and hawks are just a few of the species that will benefit from some aspect of your effort.

By following these guidelines, it will not be long until you begin hearing the whistling wavering call of the screech owl, evening and early morning. This alone may be reason enough to justify your active management for the bird.

A contribution of Marc Puckett (1992), Department of Fisheries and Wildlife Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0321

The web site of Prof. Phillip Hughes of Huntsville, Texas relating to owls of may be of interest.

This Web site is maintained by R. H. Giles, Jr.
Last revision January 17, 2000.