spotted owl
- Related Topics:
- wood owl
- northern spotted owl
What are the subspecies of the spotted owl?
What is the conservation status of the spotted owl?
How do spotted owls hunt and what do they eat?
spotted owl, (Strix occidentalis), nonmigratory species of earless North American owls best known for its strong habitat association with old-growth conifer or pine-oak forests and its use as a symbol in ongoing conflicts between logging interests and environmentalists in the Pacific Northwest of the United States. The species’ geographic range extends from British Columbia south to central Mexico and east as far as Colorado in the United States. Most taxonomies recognize three subspecies: the northern spotted owl (Strix occidentalis caurina), which lives in British Columbia, the Pacific Northwest, and northern California; the California spotted owl (S. occidentalis occidentalis), limited to California; and the Mexican spotted owl (S. occidentalis lucida), which lives in the desert southwest of the U.S. and Mexico.
Natural history
When compared with other North American owls, adult spotted owls are medium-sized, with an average length of 45–47 cm (17.7–18.5 inches) and a wingspan that ranges from 101–122 cm (about 40–48 inches). Female spotted owls may be larger than males—among Mexican spotted owls this difference is about 100 grams (3.5 ounces) on average—but adults of either sex weigh between 500 and 700 grams (1.1–1.5 pounds) generally. These birds are recognized by their mottled color pattern; their wings and heads are generally chocolate brown with patches of white and tan feathers. The chest and abdomen are primarily white and tan, the white feathers sometimes appearing as white horizontal ovals. The concentration of white feathers varies by habitat, with owls from drier environments having the highest. Spotted owls have large dark eyes, which are highlighted by white or beige feathers that form an X pattern on their facial disks. Young owls are characterized by a fluffy white down, which is slowly lost as juveniles grow.
In humid habitats, spotted owls spend the day in tree hollows or in nests abandoned by larger birds, both of which are typically found in forests shielded by a closed tree canopy—although owls from drier habitats may also nest in canyons, rock crevices in sandstone, or holes. They are nocturnal hunters that seek out small mammals (including wood rats and other rodents, voles, rabbits, and bats), other birds, insects, and amphibians by swooping down from their perches to capture prey with their talons while their victims rest on branches or cling to the sides of trees. Although most adult spotted owls are largely impervious to predation, some may be taken by raptors, including great horned owls (Bubo virginianus) and northern goshawks (Accipiter gentilis), two species that also prey on young spotted owls.
The species is largely monogamous; many pairs form lifelong bonds. Breeding occurs in late winter and early spring; however, many pairs do not nest every year. A clutch of 1–4 eggs is deposited between mid-March and mid-April, hatching after a 30-day incubation period. Parental care involves both members of the pair. The male brings food to the female, who remains with and provides food to her young. Young are capable of leaving the nest some 34–36 days after hatching, and some are capable of limited gliding between branches as early as three days after the beginning of their limited independence. Parental care will taper off as the young owls age and learn to fend for themselves, and young will disperse during the months of August and September. Both sexes become sexually mature at age one. Although spotted owls typically live for about 10 years in the wild, they can survive as long as 20 years in captivity.
Conservation status
The International Union for Conservation of Nature and Natural Resources (IUCN) has listed the spotted owl as a near threatened species since 2004. The total spotted owl population that year was estimated at 15,000 individuals; however, the results of call surveys and other studies suggest that spotted owl populations have fallen since then. The Northern spotted owl and Mexican spotted owl subspecies are considered the most at risk, and the U.S. Fish and Wildlife Service lists all three subspecies as threatened under the U.S. Endangered Species Act.
Ecologists contend that the primary driver of declines in the spotted owl population stems from habitat loss associated with the logging of old-growth forests. In addition, they note that spotted owls are also under pressure from barred owls (S. varia), which they compete with for food and living space: barred owls have driven them out of large parts of their northern habitat. These ongoing challenges have prompted the IUCN to state that it may raise the threat level of the species in the future.
Northern spotted owl controversy
The northern spotted owl subspecies is used by ecologists as an indicator species to gauge the health of old-growth forests, that is, dense climax forest communities that can take at least 150 years to fully develop (see also ecological succession). Northern spotted owls do not migrate, but they will relocate up and down slopes because of environmental challenges such as forest fires and heavy snow.
After a period of intense political and legal conflict between environmentalists (who are concerned about the owl’s population decline) and members of the timber industry (who are interested in harvesting trees in the national forests of the Pacific Northwest and protecting industry jobs), the owl was listed as threatened under the Endangered Species Act in 1990. However, it was not until 2012 that the U.S. federal government settled on a plan to set aside 9.6 million acres (3.9 million hectares) of critical habitat for the owl. Despite these steps, the northern spotted owl had lost close to 70 percent of its population by December 2020. At that time it was recommended that the owl be reclassified as an endangered species; however, this did not occur. Outgoing U.S. Pres. Donald Trump issued a rule to exclude 13.4 million acres (5.4 million hectares) of forests from northern spotted owl protections in January 2021, which was reversed under Pres. Joe Biden by November 2021. With the return of Trump to the presidency in 2025, scientists and environmentalists alike worried that rumors of his intention to undermine the Endangered Species Act would come true, abandoning the protections for several species, including that of the northern spotted owl.