Table 16. — Relation between returns to boat and lobstermen and various operating characteristics. 



Operating 

 characteristics 



Constant 

 Vessel size 



Vessel age 



Horsepower 



Crew size 



Number of traps 



Trips per week 



Average price 



Years lobstering 



Average depth 



Distance in 

 summer 



R- 

 F 



N 



'includes depreciation 

 /-values in parentheses 



frequency distribution, frequency of moult, and calcu- 

 lated growth increments. These studies indicate that 

 growth offsets natural mortality in terms of new 

 weight; therefore, if greater volume is desired it may 



80 



60 



40 



I 20 



z 



-MEAN : $ 164.19 



B ACTUAL MEDIAN =$155.73 

 I [ COMPUTED MEDIAN = $149.23 



ACTUAL AND COMPUTED TOTAL 

 WEEKLY INCOME (dollars) 



Figure 15. — Actual and computed total weekly income from a sam- 

 ple of American lobster boats, 1967. Weekly income includes return 

 to fisherman and boat. (Computed from regression in Table 16.) 



be obtained by an increase in the minimum size regula- 

 tion. Approximately 10 percent net volume increase 

 for each '/& in. minimum carapace size increase is pos- 

 sible up to at least a minimum size of 3% in. (discussed 

 earlier in Section III-A). 



Measurements of the commercial catch indicate 

 what the average carapace size and average weight 

 will be for any given minimum size from 3Vi6 in. to 3% 

 in. At 3'/iti in. average carapace size will be Wb in. and 

 average weight will be l.I pounds. At the other ex- 

 treme of 3% in. carapace average size will be 4'Vih in. 

 carapace measure and average weight will be 2.1 

 pounds. 



Obviously, trends in abundance will have profound 

 effect upon catch irrespective of legal size changes. 

 Before the last minimum size change in 1958, it was 

 predicted that the total annual catch for the next 4 yr 

 would be: 1958, 18.3 million pounds: 1959, 20.1 million 

 pounds: 1960, 20.9 million pounds: 1961. 21.2 million 

 pounds. The actual catch during this period was: 1958, 

 21.3 million pounds; 1959, 22.3 million pounds: 1960. 

 24.0 million pounds; and 1961, 20.9 million pounds, or 

 a total of 88.5 million pounds as compared with a pre- 

 dicted total of 80.5 million pounds. 



These predictions were based on an assumed con- 

 stant level of abundance derived from catch sampling 



24 



