Cervus nippon Temminck 1838
Order Artiodactyla : Family Cervidae
DESCRIPTION. A small to medium-sized deer that, due to extensive hybridization (among introduced subspecies) in Texas, is highly variable in size and coloration. In general, sika are compact in form; appear dainty legged; and have a short, trim, wedge-shaped head. Males carry antlers that average 28–48 cm in length, although exceptional racks may be up to 74 cm in length. Sika antlers have three or four points branching from a main beam; there is no palmate growth as in the fallow deer. Females have a pair of black bumps on the forehead, their placement corresponding to that of the male's antlers.
Coloration is drab brown to a deep mahogany brown mottled with numerous white spots. The degree of spotting is highly variable, however, and in some individuals spotting may be absent. The head, as well as the hair tuft over each metatarsal gland, tends to be lighter than the body. A distinctive white rump patch is evident, especially when the animal is alerted. Texas sika range in size from the smaller Japanese and Formosan varieties of 76–89 cm shoulder height and 45–80 kg to the larger Dybowski's variety of 89–109 cm shoulder height and 68–109 kg. Female Dybowski's sika stand about 81 cm in height and weigh 45–50 kg.
DISTRIBUTION. Formerly, sika deer were native from southern Siberia and the adjacent Japanese island of Hokkaido, south along both the mainland and islands, to southeastern China and Formosa. Sika deer have rapidly disappeared from much of their native range following habitat loss. Sika deer have been introduced in at least 77 counties of central and southern Texas, with free-ranging populations known from 12 of these counties. In 1994, the total statewide population was estimated to be over 5,500 individuals, about half of which were free-ranging.
HABITS. Sika are woodland deer characteristic of broad-leaved and mixed forests where snowfall does not exceed 10–20 cm and snow-free sites are also available. Large forest tracts with dense understory and occasional clearings are ideal; the patchwork of brush cover and open grassland found in the Edwards Plateau and South Texas Plains regions are well suited to these deer.
Sika deer feed on grasses, leaves, twigs, and tender shoots of woody plants, depending on seasonal availability. In Texas, the spring preference is for grasses, although browse also may be consumed regularly, and browse use increases after the flush of spring growth has passed. The most important food for sika in Texas is live oak, with hackberry, wild plum, mustang grape, Texas sotol, and greenbrier also serving as important browse species. Favored grasses include Texas wintergrass, fall witchgrass, and meadow dropseed. Forb use generally increases in summer and is lowest in winter.
Sika males are territorial and keep harems of females during the rut, which peaks from early September through October but may last well into the winter months. Territory size varies with type of habitat and size of the buck; strong, prime bucks may hold up to 2 ha (5 acres). Territories are marked with a series of shallow pits, called scrapes, into which the males urinate and from which emanates a strong, musky odor. Fights between rival males are sometimes fierce, long, and may even be fatal.
The time of fawning is primarily May through August. After a 7.5–8-month gestation period, a single fawn is born; twins are rare. Zoo longevity records typically range from 15 to 18 years, although an exceptionally long life span of 25 years, 5 months is known for one animal.
POPULATION STATUS. Introduced, common. The exotic sika deer is mostly found on managed high-fence ranches throughout the Hill Country.
CONSERVATION STATUS. The IUCN lists the sika deer as a species of least concern and increasing in number. It does not appear on any federal or state lists of concerned species. Its impact on the native flora and fauna has not been determined, but there is a need to assess its interactions with native wildlife should conservation actions become necessary in the future.
From The Mammals of Texas, Seventh Edition by David J. Schmidly and Robert D. Bradley, copyright © 1994, 2004, 2016. Courtesy of the University of Texas Press.