| Nutcrackers | |
|---|---|
 | |
| Northern nutcracker (Nucifraga caryocatactes) | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Passeriformes |
| Family: | Corvidae |
| Subfamily: | Corvinae |
| Genus: | Nucifraga Brisson, 1760 |
| Type species | |
| Corvus caryocatactes Linnaeus, 1758 | |
| Species | |
Nucifraga columbiana | |
Thenutcrackers (Nucifraga) are agenus of fourspecies ofpasserinebird, in the familyCorvidae, related to thejays andcrows.
ThegenusNucifraga was introduced by the French zoologistMathurin Jacques Brisson in 1760 with thenorthern nutcracker (Nucifraga caryocatactes) as thetype species.[1][2] The genus name is aNeo-Latin translation of an old German nameNussbrecher, "nut-breaker".[3]
Following reappraisal of species limits in the genus in Asia, the genus is now treated as containing four species:[4][5] This follows the split of Southern and Kashmir nutcrackers from a former broad view (e.g. Voous, 1977[6]) of all Eurasian nutcrackers as being a single species.
| Common name | Scientific name and subspecies | Range | Size and ecology | IUCN status and estimated population |
|---|---|---|---|---|
| Clark's nutcracker
| Nucifraga columbiana (Wilson, 1811) | WesternNorth America | Size: Habitat: Diet: | LC |
| Northern nutcracker
| Nucifraga caryocatactes (Linnaeus, 1758) Four subspecies
| Central and northeasternEurope across northern Asia east to northeast Japan | Size: Habitat: Diet: | LC |
| Southern nutcracker
| Nucifraga hemispila Vigors, 1831 | Himalayas to north China and Taiwan | Size: Habitat: Diet: | LC |
| Kashmir nutcracker
| Nucifraga multipunctata Gould, 1849 | WesternHimalayas | Size: Habitat: Diet: | LC |
The most vital food resources for these species are the seeds (pine nuts) of variouspines (Pinus sp.), principally the cold-climate (far northern or high altitude) species ofwhite pine (Pinus subgenusStrobus) with large seeds:P. albicaulis, P. armandii, P. cembra, P. flexilis, P. koraiensis, P. parviflora, P. peuce, P. pumila, P. sibirica andP. wallichiana, and also thepinyon andlacebark pines. In some regions, where none of these pines occur, the seeds ofspruce (Picea sp.) andhazel (Corylus sp.) nuts form a vital part of the diet too. Their bills are specialized tools for extracting seeds from pine cones.[7]
Surplus seed is always stored for later use, and it is this genus that is responsible for the re-establishment of their favoured pines over large areas either burnt inforest fires or cleared by man. One nutcracker can store as many as 98,000 pine nuts in a single season, and remembering the location of 75% to over 90% of their stash, even when buried in snow more than a metre deep.[7] The memory is also retained for 7–8 months, enabling them to feed their young on seed stored the previous autumn.[7][8] Nutcrackers will cache seeds as far as 32 kilometres (20 mi) away from parent plants, about eight times further than related dispersers likejays andcrows, and are thus important in re-establishing forests and responding to climate change.[7][9]
Variousinsects are also taken, includingbee andwasplarvae, and birds' eggs and nestlings, and carrion if it is found.
Nesting is always early in this genus, so as to make the best use of pine nuts stored the previous autumn. The nest is usually built high in a conifer. There are normally 2–4 eggs laid and incubated for 18 days. Both genders feed the young which are usually fledged by about 23 days and stay with their parents for many months, following them to learn food storage techniques.
None of the species aremigratory, but they will leave their usual ranges if a cone crop failure causes a food shortage.
_(52606512253).jpg)
