As of 1996, only five specimens of the Colombian weasel were known. The Colombian Weasel has been found in western Colombia as well as the Andes of northern Ecuador. Colombian weasels are considered to be riparian - to live near the bank of a body of water or a watercourse. Several specimens have been collected in areas close to water at elevations of 1750 and 2700 m (5740' and 8900'), an altitude dominated by cloud forests. One collection was in the upper Suaza River valley, where the river contains stretches with torrential currents which are interrupted by quiet pools. However, one of the most recent specimens was found in an area of rugged terrain that was not near water.
Not much information about the diet of the Colombian weasel is known. However, weasels in general are carnivores who eat up to 40% of their body weight each day. Their typical diet includes small mammals, birds, and insects. Because it is suspected that the Colombian weasel may be aquatic, fish might also be a component of their diet.