The Yezo sika deer (Cervus nippon yesoensis,[1][2] Japanese: エゾシカ / 蝦夷鹿, romanized: yezoshika,[3] Ainu: ユク yuk[4][5]) is a subspecies of sika deer that inhabits the northern Japanese island of Hokkaido. The Hokkaido sika are endemic, although it is not known whether they originated there or migrated from Honshū or areas further south. It is thought that they may have traveled across the Tsugaru Strait between the islands. Genetic study has shown that the separation of the sika population occurred less than half a million years ago.[6] It is possible that northern sika deer may be more closely related to yezo sika deer than to other sika deer.[7] The indigenous Ainu people of Hokkaido have hunted them for centuries and relied on them as a major food source.
The Hokkaido sika is one of the largest of the sika species, with mature stags approaching (and sometimes exceeding) 200 kg in the fall.[8] They also sport the largest antlers of the sika, with lengths often over 35 inches (0.89m); the longest recorded specimen had antlers measuring 44 inches (1.12m). By SCI measurement, the Hokkaido sika produces the highest scores, although very few have been listed.
^Pierre Marie Heude, 1884. Catalogue des cerfs tachetés (sikas) du Musée de Zi-ka-wei, ou notes préparatoires à la monographie de ce group. Mémoires concernant l'Histoire Naturelle de l'Empire Chinois 1:1–12.
^Bunrui Ainugo Jiten Note: according to this, it originally referred to all important game.
^An Ainu-English-Japanese dictionary (including a grammar of the Ainu language) Note: this doesn't specify the subspecies.
^Nagata, Junko; Masuda, Ryuichi; Tamate, Hidetoshi B.; Hamasaki, Shin-ichiro; Ochiai, Keiji; Asada, Masahiko; Tatsuzawa, Shirow; Suda, Kazuki; Tado, Hiroyuki; Yoshida, Michihiro C. (December 1999). "Two Genetically Distinct Lineages of the Sika Deer, Cervus nippon, in Japanese Islands: Comparison of Mitochondrial D-Loop Region Sequences". Molecular Phylogenetics and Evolution. 13 (3): 511–519. doi:10.1006/mpev.1999.0668. PMID10620409.
^Tamate, H. B.; Tsuchiya, T. (May 1995). "Mitochondrial DNA Polymorphism in Subspecies of the Japanese Sika Deer, Cervus nippon". Journal of Heredity. 86 (3): 211–215. doi:10.1093/oxfordjournals.jhered.a111564. PMID7608513.