The nutcrackers (''Nucifraga'') are a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of four

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

passerine A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped') which includes more than half of all bird species. Sometimes known as perching birds, passerines generally have an anisodactyl arrangement of their ...

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

, in the family

Corvidae Corvidae is a Cosmopolitan distribution, cosmopolitan Family (biology), family of Songbird, oscine passerine birds that contains the crows, ravens, Rook (bird), rooks, magpies, jackdaws, jays, treepies, choughs, and Nutcracker (bird), nutcrackers ...

, related to the jays and

crow A crow is a bird of the genus ''Corvus'', or more broadly, a synonym for all of ''Corvus''. The word "crow" is used as part of the common name of many species. The related term "raven" is not linked scientifically to any certain trait but is rathe ...

s. The

''Nucifraga'' was introduced by the French zoologist

Mathurin Jacques Brisson Mathurin Jacques Brisson (; 30 April 1723 – 23 June 1806) was a French zoologist and natural philosophy, natural philosopher. Brisson was born on 30 April 1723 at Fontenay-le-Comte in the Vendée department of western France. Note that page 14 ...

in 1760 with the northern nutcracker (''Nucifraga caryocatactes'') as the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

. The genus name is a

Neo-Latin Neo-LatinSidwell, Keith ''Classical Latin-Medieval Latin-Neo Latin'' in ; others, throughout. (also known as New Latin and Modern Latin) is the style of written Latin used in original literary, scholarly, and scientific works, first in Italy d ...

translation of an old German name ''Nussbrecher'', "nut-breaker".

Extant species

Following reappraisal of species limits in the genus in Asia, the genus is now treated as containing four species: This follows the split of Southern and Kashmir nutcrackers from a former broad view (e.g. Voous, 1977) of all Eurasian nutcrackers as being a single species. The most vital food resources for these species are the seeds (

pine nut Pine nuts, also called piñón (), pinoli (), or pignoli, are the edible seeds of pines (family Pinaceae, genus ''Pinus''). According to the Food and Agriculture Organization, only 29 species provide edible nuts, while 20 are traded locall ...

s) of various

pine A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. ''World Flora Online'' accepts 134 species-rank taxa (119 species and 15 nothospecies) of pines as cu ...

s (''Pinus'' sp.), principally the cold-climate (far northern or high altitude) species of white pine (''Pinus'' subgenus ''Strobus'') with large seeds: ''P. albicaulis, P. armandii, P. cembra, P. flexilis, P. koraiensis, P. parviflora, P. peuce, P. pumila, P. sibirica'' and ''P. wallichiana'', and also the pinyon and lacebark pines. In some regions, where none of these pines occur, the seeds of

spruce A spruce is a tree of the genus ''Picea'' ( ), a genus of about 40 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal ecosystem, boreal (taiga) regions of the Northern hemisphere. ''Picea'' ...

(''Picea'' sp.) and hazel (''Corylus'' sp.) nuts form a vital part of the diet too. Their bills are specialized tools for extracting seeds from pine cones. 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 in

forest fire A wildfire, forest fire, or a bushfire is an unplanned and uncontrolled fire in an area of combustible vegetation. Depending on the type of vegetation present, a wildfire may be more specifically identified as a bushfire ( in Australia), dese ...

s 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. The memory is also retained for 7–8 months, enabling them to feed their young on seed stored the previous autumn. Nutcrackers will cache seeds as far as away from parent plants, about eight times further than related dispersers like jays and

s, and are thus important in re-establishing forests and responding to climate change. Various

insect Insects (from Latin ') are Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (Insect morphology#Head, head, ...

s are also taken, including bee and

wasp A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder ...

larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

e, 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 are migratory, but they will leave their usual ranges if a cone crop failure causes a food shortage.

References

External links

Nutcracker videos
on the Internet Bird Collection {{Authority control *