28 SALMON GEAR LIMITATION 



TABLE 1. Relative Gear Efficiency Table 

 (In Numbers of Gill Net Units) 



Gill net efficiency equals 1.0 in all cases. 



Data have been rounded for uniformity in the table. Most efficiencies rounded 

 exactly to units do not have accuracy to tenths. 



the seasonal availability of gear. Two types of gear reduction patterns 

 were investigated in this study. First, the number of units fishing 

 near the peak of the season was reduced while the numbers fishing 

 in the beginning and the ends of the run were not reduced. Second, 

 a straight proportionate reduction of numbers of units was made 

 during the entire season. 



The Mathematical Description of the Fishery 



It is impossible to describe a complex system such as the salmon 

 fisheries in the state either verbally or by the usual methods of 

 mathematical analysis. The simulation approach was employed to 

 study the effect of changes in gear intensity on the economic and 

 biological sectors of the fishery. Simulation consists of tracing, step 

 by step, the actual movement of fish through each of the fishing 

 areas into the respective spawning grounds. In a similar way the 

 accumulation of earnings and expenses for the fishery was followed 

 through the entire season. An explicit mathematical description 

 of the fishery requires around 1,000 equations which must be 

 evaluated at any given time during the season. These equations were 

 translated into computer instructions. These instructions enable the 

 computer to simulate the movement of the fish through the fishery 

 and into the spawning grounds and the catches in the various areas 

 by types of gear and by time. The computer also tabulates and plots 

 the.se results in easy-to-understand tables and graphs. An entire 

 season may be simulated on the computer in 1.1 minutes. All the 



