From May to November, inclusive, the kiyis of southern Lake Michigan (north to and including localities off Kewaunee, Wisconsin, and Frankfort, Michigan) characteristically inhabit depths of more than 50 fathoms, although small numbers commonly are taken in shallower water (as shallow as 20 29 fathoms). There is evidence that the occasional penetration of relatively large numbers of kiyis into depths of less than 50 fathoms in this area is the result of exceptional hydrographic conditions involving the disturbance of considerable masses of water.