Cervus nippon keramae

Basic information
Scientific name	Cervus nippon keramae	(No picture)
Common names	Ryukyu Sika Deer
Higher taxon	Cervidae, Artiodactyla, Mammalia
Natural range	None? (This subspecies might originate from an artificially introduced population)
Habitat	This subspecies occurs in wet grassland in evening for feed, and occurs in forest in other time.

Invasion information
Range in Japan	Yakabi, Aka, Geruma, and Fukachi Is. in Kerama Islands, central Ryukyus.
Origin	Kyushu, southwestern Japan
Date	Early 17 C
Route	Deliberate: Unknown. For food? (A paleographic study suggested that the deer may be one of the viands for red-carpet treatment of emissaries from China)
Impact	Unknown Native organism(s) affected:
Regulation in Japan	This subspecies and its habitat is protected as the Natural Monument.
Introduced range in other countries	None.

Reference

Notes

Ogura et al. (2003) .A Case of Accidental Death of a Kerama Deer (Cervus nippon keramae) in Tokashiki Island. Jpn J Zoo Wildlife Med. 8(1), 55-62 (in Jpn with English abst)
Ohtaishi (1986) Preliminary memorandum of classification, distribution, and geographic variation on Sika deer. Mammal Sci. 53, 13-17 (in Jpn)
Tamate et al. (2000) .Genetic Differentiation among Subspecies of the Sika Deer (Cervus nippon), with Special Reference to the phylogeny of C. n. keramae in the Kerama Island Group. Tropics. 10(1), 73-78.
etc.

This subspecies may originate from an artifical introduction, and the small size may be an adaptation to the smal island environment. Paleographic studies suggested the age of introduction should be early 17 C. A genetic study using mitochondrial DNA sequences clarified that there is little genetic difference between this subspecies and Kyushu population of Cervus nippon.