[order] PASSERIFORMES | [family] Corvidae | [latin] Nucifraga columbiana | [UK] Clarks Nutcracker | [FR] Casse-noix d-Amerique | [DE] Kiefernhaher | [ES] Cascanueces Americano | [NL] Grijze Notenkraker
Subspecies
Monotypic species
Physical charateristics
Built like a small crow, with a light gray body and large white patches
in its black wings and tail. If these patches are seen, it should be confused with no other bird of the high mountains. Tame birds can often be fed by hand.
in its black wings and tail. If these patches are seen, it should be confused with no other bird of the high mountains. Tame birds can often be fed by hand.
Listen to the sound of Clarks Nutcracker
[audio:http://www.aviflevoland.nl/sounddb/C/Clarks Nutcracker.mp3]
Copyright remark: Most sounds derived from xeno-canto
wingspan min.: | 44 | cm | wingspan max.: | 48 | cm |
size min.: | 27 | cm | size max.: | 30 | cm |
incubation min.: | 16 | days | incubation max.: | 18 | days |
fledging min.: | 18 | days | fledging max.: | 21 | days |
broods: | 1 | eggs min.: | 2 | ||
eggs max.: | 5 |
Range
North America : West
Habitat
High mountains, conifers near treeline. Generally breeds at high elevations in the mountains, in open or broken forest of pine, spruce, or Douglas-fir. May also breed in lower-elevation pine or
pinyon-juniper woods when there is a good cone crop. Wanders to above treeline in summer, and may move to lower elevation woods in fall.
pinyon-juniper woods when there is a good cone crop. Wanders to above treeline in summer, and may move to lower elevation woods in fall.
Reproduction
Breeding activity often begins in late winter, when territory is still snow-covered. Courtship may involve long flights, male following female.
Nest: Site is in coniferous tree, usually away from trunk on horizontal limb, 8-
40′ above the ground. Nest (built by both sexes) is large and deep; has a platform of twigs and bark fibers supporting a cup of grass, bark strips, pine needles.
Eggs: 2-4, sometimes up to 6. Pale green, lightly spotted with brown and gray. Incubation is by both parents, about 16-18 days. Incubating adult sits tightly on nest even when closely approached.
Young: Both parents care for and feed young. Food for nestlings often consists of pine seeds stored the preceding autumn. Young leave the nest about 18-21 days after hatching.
Nest: Site is in coniferous tree, usually away from trunk on horizontal limb, 8-
40′ above the ground. Nest (built by both sexes) is large and deep; has a platform of twigs and bark fibers supporting a cup of grass, bark strips, pine needles.
Eggs: 2-4, sometimes up to 6. Pale green, lightly spotted with brown and gray. Incubation is by both parents, about 16-18 days. Incubating adult sits tightly on nest even when closely approached.
Young: Both parents care for and feed young. Food for nestlings often consists of pine seeds stored the preceding autumn. Young leave the nest about 18-21 days after hatching.
Feeding habits
Omnivorous. Much of diet is pine seeds; remainder of diet quite varied, including other seeds, nuts, berries, insects, snails, eggs and young of other birds, carrion.
Behavior: Forages on ground and in trees. Will pry open pine cones to extract seeds. Harvests pine seeds in late summer and fall, carrying up to 90 at once in throat pouch to bury them in soi
l on exposed slopes; may store 30,000 or more seeds in one season. Is able to find these caches later, feeding on them through winter.
Behavior: Forages on ground and in trees. Will pry open pine cones to extract seeds. Harvests pine seeds in late summer and fall, carrying up to 90 at once in throat pouch to bury them in soi
l on exposed slopes; may store 30,000 or more seeds in one season. Is able to find these caches later, feeding on them through winter.
Conservation
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be increasing, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Migration
Southwestern Canada, western United States to northern Mexico. Migration: Movements are complex and variable. O
ften a permanent resident, but may move to lower elevations in mountains in fall, even out into lowlands, perhaps in years when food crops are poor in the mountains.
ften a permanent resident, but may move to lower elevations in mountains in fall, even out into lowlands, perhaps in years when food crops are poor in the mountains.