The Northern Spotted Owl

(Strix occidentalis caurina)


The Northern Spotted Owl is found in the cool, moist woodlands of the Pacific Northwest. The Northern Spotted Owl has a round face and distinctive, dark brown eyes, but no ear tufts like those of the great horned owl. The overall color of its feathers is chestnut brown, and the tail feathers appear barred with lighter brown and white. Sometimes there is white and brown spotting on the underparts and the breast. The spotted owl is a predatory bird, and like many other species of predatory birds, the female is larger than the male. The average size of the adult spotted owl is 18 inches tall and it has a wing span of around 48 inches.
Northern Spotted Owls are not migratory birds, and they generally stay in the same area. They used to be found from southern British Columbia, Canada to western Oregon and the coastal areas of northern California, but now they are uncommon in some areas. The spotted owls found in California and Mexico are related, but slightly different.
Northern Spotted Owls prefer to live in "old growth" forests of Douglas fir , but they have been reported to occur in almost all major types of coniferous forests. They occur at higher elevations further south. For example, they occur at higher elevations in Oregon than in Washington. This is a general response to gradual latitudinal changes in vegetation and climate. Forest types in Washington and Oregon that may be 200 or more years old are:

  • Spruce/Cedar/Hemlock Forest
  • Cedar/Hemlock/Douglas-fir Forest
  • Mixed Conifer Forest
  • California Mixed Evergreen Forest
  • Silver Fir/Douglas-fir Forest
  • Red Fir Forest
  • Ponderosa Shrub Forest With White Fir/Grand Fir
  • Fir/Hemlock Forest
  • Grand Fir/Douglas-fir Forest
  • Douglas-fir Forest

    Occurrence of spotted owls in Fir/Hemlock Forest and Ponderosa Shrub Forest is usually limited to elevations where a dominant component of the forest, in both the overstory and understory, is white fir, silver fir, or both. Forest types not used by spotted owls include subalpine fir and pure stands of ponderosa pine, lodgpole pine, and Sitka spruce.

    Some general characteristics of the habitat of the spotted owl can be described as:

  • Trees relatively large in diameter in the stand

  • Multi-layered canopy of trees with a moderate to high canopy
    closure in overstory, midstory, and understory

  • Large, tall, live trees with cavities, broken tops, mistletoe, or
    platforms of branches capable of holding accumulated
    organic matter suitable for use as a nest

  • Dead standing trees and fallen decayed trees to support
    abundant populations of prey species, especially northern
    flying squirrels and woodrats

    The plants which grow close to the ground are very important to the owls, as they are used for resting or "roosting" in the deep shade during warm weather. During cold and wet weather the owls avoid the lower temperatures near the ground by roosting in the trees, which increases their exposure to the sun's warmth.
    The tops of broken trees or cavities in tree trunks are used by the owls for nests. They occasionally will use an old eagle or raven nest, but they do not build their own nests.
    The owls begin hunting just after sunset and stop shortly before sunrise, making them nocturnal animals. Their major source of food is rodents such as flying squirrels, woodrats, and gophers. They also sometimes eat birds, insects, and reptiles.
    Spotted owls hunt by sitting quietly on elevated perches and then swooping down upon their unsuspecting prey. When they are caring for their young, they store excess food and retrieve it later. The owls mate for life. The female lays eggs in about March and April and the male brings food to her. She usually lays two or three eggs and they hatch in about 30 days. For the next four to six months the male continues to do most of the hunting and the female feeds the prey to the young owlets. As the owlets mature, they begin roosting away from their parents and make longer movements at night, developing their skills as fliers and hunters, until finally, in about September or October, they leave and begin fending for themselves and looking for mates.

    Survival Statistics

    The great horned owl is the major predator for owlets, but ravens, goshawks, Coopers hawks, and red tailed hawks have also been known to kill and eat them. Very few animals prey on adult spotted owls.
    Northern Spotted Owls still inhabit a broad area, but their numbers are declining. The number of spotted owls on lands in Oregon managed by the U.S. Department of the Interior, Bureau of Land Management (BLM), is estimated at 118 pairs. There are 278 sites at which spotted owls were located in 1987. An interim agreement was entered into between the Bureau of Land Management and the Oregon Department of Fish and Wildlife to maintain 110 sites on BLM land. To ensure future survival, the owl needs special management care.

    The Federal Bureau of Land Management and the U.S. Forest Service are developing land use plans which will provide the opportunity to manage areas of habitat to maintain a healthy population of the owls. Of course, the owl is not the only species which will benefit from land use plans. Managing forest habitats for owls will also provide many other wildlife species with places to live.

    Some literature indicates that the population of Spotted Owls is all the way down to a mere 1200 pairs in Oregon, 560 pairs in northern California, and only 500 pairs in the whole state of Washington. Even though the adult owl doesn't have any major predator in the way of animals, you could say the most dangerous predator is man himself.