The Nutcracker (Nucifraga caryocatactes) is a passerine bird slightly larger than the Eurasian Jay. It has a much larger bill and a slimmer looking head without any crest. The feathering over its body is predominantly a chocolate brown with distinct white spots and streaks. The wings and upper tail are virtually black with a greenish-blue gloss.
This species has an extremely extensive range forming a broad swathe east-west from Scandinavia right across northern Europe, across Siberia and right over to the eastern Asian seaboard (including Japan).
Two further populations occur also, one centered on the Alps in central Europe, the other in the Himalayas across to the Chinese seaboard and separated from the northern population by a relatively small region in Manchuria. It inhabits the huge taiga conifer forests in the north and mountain forests elsewhere. Some of the populations can be separated on bill size.
The two most important food resources for this species are conifer seeds principally of Spruces (Picea sp.) and various Pines (Pinus sp.). Hazel nuts (Corylus sp.) form an important part of the diet in some regions too, and the forms that take these have thicker bills for cracking their hard shells, with a special ridge on the inside of the bill edge near the base. If the shell is too hard, it holds the nut between its feet and hacks at it with its bill like a chisel.
Various insects are also taken, and also birds' eggs and nestlings, and it will take meat from trappers fur traps, including fish if that is used as bait. It digs out bumble bee and wasp nests avidly to get at the grubs.
Surplus seed is always stored for later use and it is this species that is responsible for the re-establishment of the Swiss Arolla Pine (Pinus cembra) to large areas in the Alps of central Europe formerly cleared by man .
Nesting is always early in this species across its whole range and the nest itself is usually built up high in a conifer (sometimes broadleaved trees are used) and usually on the sunny side. There are normally 2-4 eggs laid and incubated for 18 days. Both sexes feed the young which are usually fledged by about 23 days and stay with their parents for 3-4 months, following them around.
The voice is very like the Eurasian Jay and is loud and harsh. It is described as kraak-kraak-kraak-kraak.
This species is not migratory, but will erupt out of range when its food supply fails, the thick-billed eastern race being the most likely to do this. Vagrants of this species to western Europe can be very confiding, and birds in both The Netherlands and England were photographed standing on birder's heads.
There is another species in the same genus: Clark's Nutcracker, Nucifraga columbiana.