Recognition. Intermediate in size between roe and red deer. Similar pelage to fallow deer, but darker. Reddish brown to yellow-brown, dark dorsal stripe surrounded by white spots in the summer. Dark grey to black, spots faint or absent during the winter. Tail shorter and with less distinct stripe than fallow. Very distinct white gland on hind leg.
Adult size. Stags (males): 40 to 70 kg, 70 to 95cm at shoulder. Hinds (females): 30 to 45kg, 50 to 90cm at shoulder, dependent on subspecies.
Antlers. Branched, similar to red deer but with a maximum of eight points. Bey tine absent. Angle between brow tine and the main beam is always less than 90?.
Lifespan. Exceptionally up to 18 years.
Status. Introduced, locally abundant and increasing.
UK distribution. Widespread and expanding in Scotland from west to east. Strong population in Peebles-shire. Patchy in England (bands exist across the north and south) and Northern Ireland (County Fermanagh and County Tyrone), absent from Wales.
Habitat. Coniferous woodlands and heaths on acid soils.
Food & feeding. Grazers of grasses and dwarf shrubs, especially heather. Coniferous tree shoots and tree bark may occasionally be taken in small quantities.
Origins & history. Sika were first introduced from the Far East into Britain in 1860. Several subspecies, including Chinese, Japanese, Formosan and Manchurian were introduced into parks but the only free living form in Britain is the Japanese sika. It is possible that almost if not all English and Scottish and some Irish living sika are descendants from only one stag and three hinds introduced to Viscount Powerscourt's deer park at Enniskerry, Eire in 1860.
Social organisation. Sika are fairly unsocial, tending to be solitary for most of the year and only form small groups in winter. The sexes are strongly segregated and occupy discrete geographic ranges for most of the year, only coming together to mate.
Vocalisation. Sika have a wide repertoire of vocalisations. Stags groan, blow raspberries, yak-yak and give a high-pitched whistle during the rut or can emit a startling scream! Hinds with calves whine and calves reply with a bleat or squeak. When alarmed both sexes give a short, high-pitched bark.
The rut. The breeding season, or rut, occurs from the end of September to November. The environment has a strong influence on mating strategy. Typically stags defend a rutting territory, much like fallow deer, and they may also switch to harem-holding when a group of hinds has been assembled. Less typically, males may congregate to form a lek or may simply wander throughout the hinds' range in search for receptive hinds.
Breeding. A single calf (rarely twins) is born during early May to late June after a gestation period of 7 ½ months.
Activity. Sika are active throughout the 24-hour period but are more active during the hours of darkness in populations experiencing frequent disturbance.
Economic factors. Browsing of tree shoots and agricultural crops and bark stripping and bole scoring (gouging with the antlers) of plantation trees puts sika in conflict with farmers and foresters due to economic damage. Conversely, many country and forest estates can gain substantial revenue from recreational stalking and/or venison production. Whether in conflict or used as a resource, sika populations require careful management to maintain health and quality and ensure a sustainable balance with their environment. Sika are becoming regarded as a pest in areas of conflict since the damage that they cause is serious and the rate of hybridisation with red deer alarming.
Hybridisation appears to be most pronounced at the edges of population ranges where both species meet. The first cross between the species has the appearance of both parents, but subsequent crosses result in the hybrid having the dominant parental appearance. This makes selective culling impossible, potentially reduces income from sport shooting and poses a major threat to the genetic integrity of native red deer. Indeed, some would say that there are no pure bred red deer surviving in mainland Britain and only sika in the New Forest and Peebles-shire remain pure.