ORIGINAL: bull3540
The sika, not being native to the U.S., is an exotic. They do not compete with whitetail deer. There are wild populations in several states including Texas. They tend to wallow in mud and can be found in creeks and riverbeds. Native to Japan they are shorter than whiletail deer, and have a shaggy coat that runs from dark red to brown, with some of the subspecies having spots similar to axis.
http://www.dnr.state.md.us/wildlife/sikadeer.asp
pics here;
http://www.thewildliferanch.com/sikadeer.htm
While exotics such as the sika can shift their feeding from forbs to grass, whitetails will die with a bellyfull of grass, thus leading to the inaccurate conclusion that they "run out" native deer from habitat that is really only subprime whitetail range. Numbers of sika and other exotics are above 250,000 in Texas alone.
http://www.tpwd.state.tx.us/huntwild/wild/game_management/deer/exotics/