Whitefish (Prosopium coulteri) are small, slim whitefish with relatively large scales, a blunt snout and almost cylindrical bodies. Pygmy whitefish have a wide, but disjunct distribution in northern North America. The few specimens that have been found in Alberta have been from Waterton Lake and parts of the upper Athabasca River drainage. It is likely that the main reason the data for pygmy whitefish are so sparse in Alberta is that people have misidentified pygmy whitefish as juveniles of their much more abundant relative, the mountain whitefish, which occurs in the same stream
habitats. There is no designation for the species by the
Committee on the Status of Endangered Wildlife in Canada
to date, but it has been proposed that the Alberta population be listed as
Pygmy Whitefish are small (maximum size 65-260 millimetres) and slim.
Individuals that are less than 10-12 centimetres total length have 7-14 distinct dark round to oval markings on the sides along the lateral line as well as
12-14 similar spots along the middle back. The oval markings along the sides are similar to the dark markings, called
"parr marks", which are found along the sides of many juvenile salmonids. These markings, together with the species' small size as adults can lead to misidentification of
Pygmy Whitefish as juveniles of other whitefish species. The main external features that distinguish pygmy whitefish from other species are their rather elongated heads, relatively large eye, blunt snout, and small adipose fin.