Jock Mock is a small lake in the Cascade River (Lake Superior) watershed. The survey history for the lake is sparse, but shows a fish community that has grown increasingly complex over the years. No fish were collected in surveys or assessments done in 1953, 1960, and 1969. More recent assessments have found smallmouth bass, walleye, white sucker, and northern pike. No yellow perch have ever been found in this lake, and muskellunge (stocked in 1977 and present until 1979) appear to have died out.
The walleye gill net catch in the 2011 assessment was within the normal range for a lake of this class. All walleye collected had been produced naturally. Five year classes, none particularly strong, contributed to the catch. With yellow perch apparently absent, walleye diet likely consisted of minnows and invertebrates. Despite this limited forage, walleye growth had been average or a little better, compared to similar lakes in the area.
The northern pike gill net catch fell below the normal range for the lake class, but was consistent with catches seen in this lake in the past. Although no large northern pike were taken, most were larger than 20 inches, resulting in a mean weight that exceeded the normal range for the lake class. Three age classes contributed to the 2011 catch. Growth of young northern pike had been relatively fast. Fish reached an average length of 16.6 inches by the end of their second year, compared to an area average of 12.0 inches.
Smallmouth bass were present in 2011, and all fish taken were over 12 inches in length. Smallmouth bass growth had also been fairly fast. No white sucker were taken in 2011.