The body of the northern spotted owl measures about 17-1/2 inches. The owl's wingspan reaches 42 inches. Its tan or brown beak is placed in the center of a rounded face, on a tuftless head. Their huge dark eyes help gather light and enables the owls to hunt at night; they are nocturnal creatures. Their name "spotted" derives from the white spots among their brown feathers.

The hoot of this owl sounds similar to the bark of a medium-sized dog.

The Northern spotted owl has recently come under scrutiny because it requires old-growth forests to survive. This interdependency has made people stop and think about the amount and intensity of logging that is being done in the Pacific Northwest. The presence of the spotted owl in old-growth forests has curtailed the timber harvesting in some of these areas.

The spotted owl is part of the old-growth forest food web that includes truffles, flying squirrels, and voles. Truffles are fungi that grow on the roots of old-growth trees and are feasted upon by flying squirrels and red-backed voles. Spotted owls prey upon squirrels and voles.

The fungi's root-like system, called mycelium, is far-reaching. This massive network of thread-thin mycelium sheaths the root ends of the tree and thereby helps the tree to capture nutrients by expanding the tree's root system. The squirrel and vole help perpetuate the population of fungi by passing the seeds, called spores, through their digestive systems and excreting them throughout the forest to grow in different locations.

The elements of this food web are tied to other parts of different forest cycles. It is a complex system in which all parts are necessary parts. Thus the decline in the population of spotted owls may be an indicator of widespread problems in old-growth habitat.