Fishing Mortality 197 



fyke or wing nets for largemoiith bass and bluegills.'^ Six 1-inch-mesh wing 

 nets with leads were set across a 1.38-acre pond in two gangs so as to 

 completely block the pond at two points (Figure 7.4). These nets were 

 fished for 96 to 149 hours each month, from March to November of each 

 year for two and one-half years, and all fishes captured were removed, 

 regardless of size or species. These nets held bass as small as 9 inches and 

 bluegills as small as 5 inches. The catch consisted largely of bluegills, as 

 the bass soon avoided the nets. Supplementary cropping was done by 

 hook-and-line. At the end of the study period the bluegill population 



Figure 7.4. Outline map of Fork Lake (Illinois) showing the customary 

 arrangement of wing nets and lead nets for cropping studies. No fish could 

 swim for any great distance in this 1.38-acre pond without running into a lead 

 net or wing net. Arrows mark openings of wing nets. [From Bennett, G. W., 

 Ill Nat. Hist. Bull, 24(3) (1948)] 



amounted to about 67 pounds per acre and the bass to over 120 pounds 

 per acre. The netting operation unquestionably was a major influence in 

 the buildup of a very large population of bass. 



In some states commercial fishermen have been forced out of business 

 except on the major rivers, and the state fisheries departments have had 

 to assume the task of controlling rough fish. This is an expensive never- 

 ending job, and when commercial fishing is outlawed, rough-fish removal 

 must be paid for by the sport fishermen. However, in states where com- 

 mercial fishing is legal, rough-fish removal is self-sustaining and the com- 

 mercial man operates at a profit. 



Many studies show that removing large crops of coarse fish with com- 

 mercial gear is beneficial or at least not harmful to sport fishing. This is 

 universally true in large shallow lakes and reservoirs containing sub- 

 stantial numbers of coarse fish which, because of low fishing pressure, 

 are not cropped by hook-and-line.^- Here commercial fishing is about the 



