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Northern Spotted Owl
Chenoa & Luna
Chenoa the larger bird is female and was the first product of a breeding physiology
research project. She was bred in captivity in 1994 and fostered into a wild
family as a fledgling. She was not adopted and could not hunt on her own and
was recaptured, starving. She was transferred to CRC in October 1994 because
US Fish & Wildlife felt she could better serve her species in education than
by dying in the wild, as do between 60% and 90% of the young of each year.
Luna the smaller bird is male and was found as a dispersing juvenile in October
2000 on a golf course near Salem. Both wings were broken and though one
healed well, the other healed in poor alignment and he is unable to fly well
enough for release.
Read about a Northern Spotted Owl release in 2004.
Northern Spotted Owl (Strix occidentalis caurina)
This owl lives in the deep forests of the Pacific Northwest, with camouflage
feathering to blend with patterns of dim light filtering through tree
branches. Like the related Barred Owl, this species has a stocky body, short
tail, and broad wings; the sexes are similar, but the female is generally
larger. The large head is rounded and lacks ear tufts; a facial disc with a
feather pattern of concentric barring surrounds large, dark brown eyes. The
head and upperparts are dark brown, irregularly spotted and speckled with
white. The under parts are dark brown and buff, with large, white, rounded
spots, and barring across the belly. The Northern Spotted Owl can be
distinguished from the Barred Owl in its darker color, smaller size, lack of
streaking on the belly, darker face, and greenish, horn-colored bill. Fledglings of the Northern Spotted Owl have a narrower pattern of bands on
the wings than fledglings of its relative.
Notes
Size - Length: 17.5" ave. • Wing Span: 40" ave. • Weight: 1.3 lb. ave.
Status - State and federally protected;
listed as Threatened under the Endangered Species Act.
Habitat - The Northern Spotted Owl lives
in mature to old-growth coniferous forests and typically requires large
territories. Avoids open areas, where it is vulnerable to predation by the
Great Horned Owl; has been found nesting in managed stands of second-growth
redwoods, where the growth of shoots from redwood stumps creates excellent
habitat for wood rats, which have become the favored prey of the Spotted Owl
in that habitat.
Diet - Small mammals, primarily rodents,
are the major part of the diet. The Northern Flying Squirrel is the single
most important prey species. This nocturnal to semi-nocturnal owl is an
opportunistic hunter, and will also take birds, fish, reptiles, amphibians,
and insects. The most common hunting technique is diving down on prey from
an elevated perch.
Call - The call most often heard is a
four or five note, barking call of whoooo...oowho,oowhooo. Resembles the
Barred Owl call, but higher in pitch and a shorter series of notes.
Nesting - Almost all Northern Spotted
Owl nests are found in old-growth conifers near water. About 65% of nests
are found in tree cavities or the broken top of trees where branches have
grown up to cover the old top, and 35% of nests are moss platforms on
horizontal branches or stick constructions, usually built by other species.
Most Common Problems - Collisions with
vehicles. Destruction and fragmentation of habitat from logging, and
degrading of habitat through policies of even-aged tree management are the
major threat to this species.
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