These elegant creature's fur is brown above and cream on it's underparts. They are long and fully suited to their habitat being able to propel itself fast through the water with their long tail. It is usually 23-27 inches long with it's tail being 14-18 inches in length. Strangely, the female is shorter than the male. They usually weigh in at 15.4-37 lbs. By an anonymous and un-verified source, the largest specimen in captivity was 53 lbs.