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| − | ;Glaucidium californicum | + | '''Alternative names: California Pygmy-Owl; Rocky Mountain Pygmy-Owl; Vancouver Pygmy-Owl''' |
| − | [[Image:Northern_Pygmy_Owl.jpg|thumb|550px|right|Photo by jmorlan]] | + | ;[[:Category:Glaucidium|Glaucidium]] gnoma |
| − | '''Other names:''' Northern Pygmy Owls have also been called Pygmy Owl, Rocky Mountain Pygmy Owl, Vancouver Pygmy Owl, California Pygmy Owl, and Dwarf Owl. | + | '''Includes: Mountain Pygmy-Owl; Guatemalan Pygmy-Owl; Cape Pygmy-Owl, Baja Pygmy Owl''' |
| | + | [[Image:Northern_Pygmy_Owl.jpg|thumb|550px|right|A bird of the ''californicum'' group<br />Photo by {{user|jmorlan|jmorlan}}]] |
| | ==Identification== | | ==Identification== |
| − | The Northern Pygmy Owl is a tiny, woodland, diurnal Owl that is most active between dawn and dusk. It has greyish or brownish or reddish (3 morphs; intermediates are also known) upperparts and light belly that is boldly streaked with brown. The head and nape are liberally sprinkled with whitish dots (more cinnamon or buff on red morph). On the nape are 2 distinctive, vertical black patches that resemble an extra pair of eyes. The relatively long tail is distinctly barred with 6 to 7 light stripes. Eyes are yellow, bill is yellowish-horn, and the toes are greyish-yellow.
| + | 18.5 cm. It has greyish or brownish or reddish (3 morphs; intermediates are also known) upperparts and light belly that is boldly streaked with brown. The head and nape have whitish dots (more cinnamon or buff on red morph). On the nape are 2 distinctive, vertical black patches that resemble an extra pair of eyes. The relatively long tail is distinctly barred with 6 to 7 light stripes. Eyes are yellow, bill is yellowish-horn, and the toes are greyish-yellow. Juveniles are similar to adults but with unspotted and greyer heads, and fluffy plumage. |
| − | Juveniles are similar to adults but with unspotted and greyer heads, and fluffy plumage. | |
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| − | Size: Average Length Female: 18.5 cm (7.3"), male: 16.5 cm (6.5")
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| − | Average Wingspan 38 cm (15")
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| − | Average Weight Female 73 g (2.6 oz), Male 62 g (2.2 oz).
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| | ==Distribution== | | ==Distribution== |
| − | West North America, from British Columbia and southern Alaska south through the Rock Mountains to California and Arizona, and possibly also to the mountains far north Mexico. In its western and Sierra range it is associated with blue oak savanna to montane conifer forests. Its normal range is about 3000 - 6000 ft. in elevation. It may move into lower elevation in the winter months and alternately nest as high as 8000 ft. in the Sierras (it is rare on the east slope of the Sierras) the highest frequency is at 4000 - 5000 ft. in elevation. In the Rocky Mountains the Northern Pygmy may range as high as 12,000 ft. and may also descend into lower prairie habitats well away from forests.
| + | From [[Alaska]] south over western [[North America]] to [[Mexico]] and south to [[Guatemala]] and [[Honduras]]. |
| − | Northern Pygmy Owls are essentially sedentary, except for altitudinal movements downslope in winter. Southward irruptions during winter may occur in years of food shortage.
| + | ==Taxonomy== |
| | + | [[Image:Cape_Pygmy_Owl.jpg|thumb|400px|right|Cape Pygmy-Owl<br />Photo by {{user|van_ellus|van_ellus}}<br />[[Mexico]].]] |
| | + | Consists of several subspecies which are sometimes accepted as full species. |
| | + | * '''Northern Pygmy-Owl''' group (''Glaucidium californicum'') or Pacific Pygmy-Owl |
| | + | ** ''G. g. grinnelli'' from [[Alaska]] to northern [[California]] |
| | + | ** ''G. g. swarthi'' on Vancouver Island |
| | + | ** ''G. g. californicum'' from [[British Columbia]] to southwest [[USA]] and northwest [[Mexico]] |
| | + | * '''Rocky Mountains Pygmy-Owl''' (Glaucidium pinicola) |
| | + | ** ''G. g. pinicola'' in the Rocky Mountains of west-central [[USA]] |
| | + | * '''Mountain Pygmy-Owl''' (''Glaucidium gnoma'') |
| | + | ** ''G. g. gnoma'' from [[Arizona]] to the highlands of [[Mexico]] |
| | + | * '''Cape Pygmy-Owl/Baja Pygmy Owl''' (''Glaucidium hoskinsii'') |
| | + | ** ''G. g. hoskinsii'' in Baja California, [[Mexico]] |
| | + | * '''Guatemalan Pygmy-Owl''' (''Glaucidium cobanense'') |
| | + | ** ''G. g. cobanense'' from south [[Mexico]] (Chiapas) to [[Guatemala]] and [[Honduras]] |
| | + | Some authorities split all these groups as full species. However, most of the world-wide checklists don't. |
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| − | ==Taxonomy==
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| − | Once considered a subspecies of [[Mountain Pygmy Owl]] ''Glaucidium gnoma''. The bird pictured from San Mateo County, California is of the nominate subspecies ''Glaucidium c. californicum''. Two other subspecies exists, ''swarthi'' is a dark subspecies from [[Vancouver Island]], and ''pinicola'' in eastern part of range, possibly to northern [[Mexico]].
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| | ==Habitat== | | ==Habitat== |
| − | Northern Pygmy Owls inhabit open coniferous and mixed forests from valley bottoms up to treeline. They do not inhabit dense, continuous forest. In all areas they use forest clearings for hunting - along the edges of meadows, fields, wetlands, and roadsides, and through old burns and logged areas. For roosting they prefer quiet, shady alder thickets. During the breeding season they inhabit open forests with a selection of snags with old woodpecker cavities. They always have a demand for old trees being present.
| + | Open coniferous and mixed forests from valley bottoms up to treeline. |
| | ==Behaviour== | | ==Behaviour== |
| | This is a diurnal owl (active in daytime). | | This is a diurnal owl (active in daytime). |
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| − | Northern Pygmy Owls are very secretive and tend to perch and roost in thickets where it is safe from predators. At times, one will sit atop the highest spire of a tree. At rest, a Northern Pygmy Owl sits with its tail cocked away from vertical, and often twitches its tail when excited. A Northern Pygmy Owl's flight between perches is short and rapid - plummeting downwards as it leaves a perch before levelling off, and swooping up to the next. If the next perch is a tree, it will tend to land low, then moves up through the tree to a higher perch. Flight is relatively noisy for an owl, and resembles a shrike, with rapid wing beats and rounded wing tips.
| + | Diet includes small mammals, small to medium sized birds, reptiles, larger insects, and amphibians within their range. The Owl's preference seems to be mice, birds, and large insects with studies indicating that about 90% of their diet is comprised of small mammals and birds. During winter, surplus prey is cached in a cavity, often in large quantities. These caches help small owls like these meet their metabolic needs during very cold winter periods. Summer caches are usually much smaller. |
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| − | Despite their small size, Northern Pygmy Owls are quite fierce, and will attack prey or drive off intruders several times their own size. The list of possible prey in the Northern Pygmy-Owl's diet is quite large. This may include all of the small mammals, small to medium sized birds, reptiles, larger insects, and amphibians within their range. The Owl's preference seems to be mice, birds, and large insects with studies indicating that about 90% of their diet is comprised of small mammals and birds.
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| − | When one of these owls is threatened, it will puff up its feathers and spread its tail to make itself look larger. When hiding, it tries to look thin, faces the danger, and closes its eyes into slits. In relation to humans, this little owl is very bold and will often allow a very close approach. Although it is not brightly colored, it very often brings a crowd of mobbing songbirds along with it that will betray its location.
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| − | Voice: The primary call of the male is a series of repetitive, whistled hoots "too-too-too-too-too-too-too" at intervals of 1 to 2 seconds, although it is reported that this can vary from 0.5 seconds, all the way up to 4 seconds. This call is territorial in nature and is usually given in the early evening and before dawn, and may be heard year-round (actively vocalizes most in March through mid-June and September through October). The male gives a high whinnying sound when bringing food to his mate. The female calls much less often and it has a cackling quality. Other calls include an ascending staccato series of whistles. When excited, they may emit a high-pitched trill (8 notes/second).
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| − | Hunting & Food: Northern Pygmy Owls are "sit and wait" predators, that hunt mainly by vision, diving down onto prey on the ground and driving the talons into the prey's throat. they will also attack birds in shrubs, crashing into the hapless victims. Most prey is carried off in the feet to feeding sites. Birds are usually plucked before being consumed. They often eat only the brains of birds and the soft abdomen of insects! One of these little owls can carry prey weighing up to 3 times its own weight.
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| − | The Northern Pygmy Owl feeds on a wide range of small prey including small mammals, birds, and reptiles and amphibians. Voles make up the bulk of their diet, with birds comprising most of the rest (mainly songbirds, but as large as a California Quail). Other small mammals include shrews, mice, chipmunks, bats, moles, young rabbits, and weasels. Insects may be very important when they are most abundant. Other prey taken are toads, frogs and small lizards and snakes.
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| − | During winter, surplus prey is cached in a cavity, often in large quantities. These caches help small owls like these meet their metabolic needs during very cold winter periods. Summer caches are usually much smaller. | |
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| − | Pellets are very small, averaging about 3cm (1.2") long. They are formed only occasionally as these owls don't consume large amounts of fur, feathers, or bone. The pellets tend to fall apart shortly after ejection.
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| − | Breeding: Northern Pygmy Owls are unsociable birds, remaining solitary much of the year. During courtship both sexes call to each other with their mating trill. They also pass food to each other and snuggle closely.
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| − | Northern Pygmy Owls are almost entirely dependent on old woodpecker cavities for nest sites. They will also nest in natural tree cavities. Nest trees are usually dead and are usually coniferous in the boreal forest and deciduous in more southern areas. Nest cavities range from 3 to 23 metres (10 to 75 feet) above ground, averaging 6 to 7 meters (20 to 23 feet). Eggs are laid between April and June, with clutch size ranging from 3 to 7 (3 - 4 average; may increase from south to north). The female does the incubating and brooding while the male brings food and defends the nest. The incubation period is about 29 days. Unlike all other North American owls, The Northern Pygmy Owl begins incubation only after the clutch is complete, so that young tend to hatch over a period of 1 to 2 days, rather than one every 1 to 2 days. The male feeds the incubating and brooding female for approximately 9 days after eggs hatch at which time the female will begin to forage. Young grow quickly, reaching 60% of adult size after 2 weeks. They fledge at about 30 days, when they are capable of flight. Fledglings are then fed and defended by their parents for a further 20 to 30 days. Family groups tend to break up in late Summer or Autumn. Signs of sexual maturity begin to show at only 5 months although the age of the first breeding is probably 1 year. Northern Pygmy Owls are single-brooded. It is not known if replacement clutches are laid. Nest cavities may be used for several consecutive years by the same birds.
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| | + | They nest in natural tree cavities. 3 to 7 eggs are laid and incubated by the female for about 29 days, while the male brings food and defends the nest. |
| | + | ==References== |
| | + | #{{Ref-Clements6thDec09}}#{{Ref-HBWVol5}}#[http://birdforum.net/showthread.php?p=2231875 Birdforum thread] discussing Guatemalan Pygmy Owl |
| | + | {{ref}} |
| | ==External Links== | | ==External Links== |
| − | {{GSearch|Northern+Pygmy+Owl}} | + | Search the Gallery using the scientific name: |
| | + | {{GSearch|Glaucidium+gnoma}} |
| | + | Search the Gallery using the common name: |
| | + | {{GSearch|"Northern Pygmy Owl"}} |
| | + | {{GS-checked}} |
| | + | <br /> |
| | + | <br /> |
| | + | <!--GSearch for original sci name deleted as no images found after 12 years. Replaced by common name search--> |
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| − | [[Category:Birds]] | + | [[Category:Birds]][[Category:Glaucidium]] |
Alternative names: California Pygmy-Owl; Rocky Mountain Pygmy-Owl; Vancouver Pygmy-Owl
- Glaucidium gnoma
Includes: Mountain Pygmy-Owl; Guatemalan Pygmy-Owl; Cape Pygmy-Owl, Baja Pygmy Owl
A bird of the
californicum group
Photo by
jmorlanIdentification
18.5 cm. It has greyish or brownish or reddish (3 morphs; intermediates are also known) upperparts and light belly that is boldly streaked with brown. The head and nape have whitish dots (more cinnamon or buff on red morph). On the nape are 2 distinctive, vertical black patches that resemble an extra pair of eyes. The relatively long tail is distinctly barred with 6 to 7 light stripes. Eyes are yellow, bill is yellowish-horn, and the toes are greyish-yellow. Juveniles are similar to adults but with unspotted and greyer heads, and fluffy plumage.
Distribution
From Alaska south over western North America to Mexico and south to Guatemala and Honduras.
Taxonomy
Consists of several subspecies which are sometimes accepted as full species.
- Northern Pygmy-Owl group (Glaucidium californicum) or Pacific Pygmy-Owl
- Rocky Mountains Pygmy-Owl (Glaucidium pinicola)
- G. g. pinicola in the Rocky Mountains of west-central USA
- Mountain Pygmy-Owl (Glaucidium gnoma)
- Cape Pygmy-Owl/Baja Pygmy Owl (Glaucidium hoskinsii)
- G. g. hoskinsii in Baja California, Mexico
- Guatemalan Pygmy-Owl (Glaucidium cobanense)
Some authorities split all these groups as full species. However, most of the world-wide checklists don't.
Habitat
Open coniferous and mixed forests from valley bottoms up to treeline.
Behaviour
This is a diurnal owl (active in daytime).
Diet includes small mammals, small to medium sized birds, reptiles, larger insects, and amphibians within their range. The Owl's preference seems to be mice, birds, and large insects with studies indicating that about 90% of their diet is comprised of small mammals and birds. During winter, surplus prey is cached in a cavity, often in large quantities. These caches help small owls like these meet their metabolic needs during very cold winter periods. Summer caches are usually much smaller.
They nest in natural tree cavities. 3 to 7 eggs are laid and incubated by the female for about 29 days, while the male brings food and defends the nest.
References
- Clements, JF. 2009. The Clements Checklist of Birds of the World. 6th ed., with updates to December 2009. Ithaca: Cornell Univ. Press. ISBN 978-0801445019.
- Del Hoyo, J, A Elliot, and J Sargatal, eds. 1999. Handbook of the Birds of the World. Volume 5: Barn-Owls to Hummingbirds. Barcelona: Lynx Edicions. ISBN 978-8487334252
- Birdforum thread discussing Guatemalan Pygmy Owl
Recommended Citation
External Links
Search the Gallery using the scientific name:
Search the Gallery using the common name:
GSearch checked for 2020 platform.
