LENARZ and ZWEIFEL: INTERACTION BETWEEN LONGLINE AND SURFACE FISHERIES 



32 36 



MULTIPLIER OF EFFORT 



Figure ll. — Estimates of yield per recruit at size at recruitment at the time of the study as a function of fishing effort, sex ratio 

 h>'pothesis, and fishing gear when only one gear is fishing: (a) high InputF and surface gear, (b) high InputF and longline gear, (c) low 

 Input F and surface gear, and (d) low Input F and longline gear. 



3 



< 



HIGH M 



MULTIPLIER OF EFFORT 



Figure 12. — Estimates of relative stock fecundity at size at recruitment at the time of the study as a function of fishing effort, fecundity 

 index, and sex ratio hypothesis: (a) high Input F and fecundity index I, (b) high Input F and fecundity Index II, (c) low Input F and 

 fecxmdity index I, and (d) low input F and fecundity index II. 



With the above results in mind, we developed a 

 computer simulation model to examine the inter- 

 relationships of: 1 ) patterns of movement offish; 2 ) 

 patterns of recruitment (i.e. by area), and 3) 



fishing strategy for two gear types (surface and 

 longline) fishing alone or together on the same 

 population. 



The model is general in that it allows the user to 



817 



