

1 









Month Tagged 



No. ol 









No. 

 1. 



SWFC No. 

 (235) 



-Recovered 



Days Out 



9-10 



408 



"3 







2. 



(238) 



10-10 



367 









3. 



(241) 



11-11 



723 









4. 



(240) 



10-11 



397 









5. 



(256) 



12-10 



416 









6. 



(136) 



10-11 



400 







7. 



(258) 



10-10 



367 







8. 



(206) 



9-10 



404 









9. 



(282) 



9-11 



403 



- 



Ira 





10. 



(237) 



9-10 



402 





^\6 



11. 



(255) 



10-12 



413 







*7/\ 



12. 



(220) 



10-10 



370 







^V'w 



























c/im/vs\ 





10 



11 









AUSTRALIA 













1 









i& 



^ 



Figure 7. — Tag and recovery locations, 366d-2 yr time at large. Lines indicate point 

 of tagging and recovery only. 



Month Tagged No. of 

 No. SWFC No. -Recovered Days Out 



1. 



(239) 



11-11 



733 



2. 



(261) 



10-10 



1.453 



3. 



(281) 



10-10 



758 



4. 



(260) 



11-11 



747 



Ho SWFCNc 



-flra»«d 



IB <* dan 0* 



1 (120) 



iO-« 



ISO 



2 ('■") 



10-3 



141 





11-tJ 





4 1230) 







5 1203) 



i^a' 



X 



r (ion 



»"I 



K 





Figure 9. — All recoveries 500 nmi or greater from location of tagging. Lines indicate 

 point of tagging and recovery only. 



average distances of tagging to recapture points increase from 

 time of tagging for at least the first 180 d of time at large. A 

 regression was calculated for recaptures made within the first 235 

 d from time of release. Recapture distances by number of days 

 from release are given in Figure 10. The greatest recorded distance 

 between tagging and recapture was 2,100 nmi, 235 d after release. 

 Recaptures made near the tagging area (within 210 nmi) were 

 common 1 and 2 yr after tagging (17 at 1 yr, 4 at 2 yr) and one 

 recapture at nearly 4 yr after release (1,453 d or 3.98 yr). 



The average migration rate in nautical miles per day (nmi/d) 

 away from the location of tagging, for selected time periods 

 subsequent to tagging, was calculated using two methods from 

 data derived from time, straight line distance, and true bearing 

 angle measurements from the tagging point to the recapture 

 point. Of particular interest are the data obtained from recaptures 

 within the first three time periods selected (0-60, 61-120, and 

 121-240 d) since these data may better define the average migra- 

 tion rate of black marlin away from a high population density (as 

 reflected in CPUE) and reported spawning area. The greatest 

 observed migration rate for any black marlin recaptured was 22.3 

 nmi/d, an average attained during a release time of 30 d. Average 

 movement was calculated in nautical miles per day for the first 

 three time periods, then multiplied by the average number of days 

 within the period in relation to zero day, or start of the first time 

 period, to obtain the approximate average distance of migration: 





Midpoint 





To period 



Days 



in time 



Avg. nmi/d 



midpoint 



0-60 



30 



3.65 



109.5 nmi 



61-120 



40 



6.08 



547.2 nmi 



121-240 



180 



7.70 



1,386.0 nmi 



Figure 8. — Tag and recovery' locations, 2 to 3 yr and 3 to 4 yr time at large. Lines in- 

 dicate point of tagging and recovery only. 



The percentage of recaptures by month of tagging was August 

 30%, September 30%, October 49%, November 17%, and De- 

 cember 2%. Recaptures made within the first period (0-60 d) were 

 examined to determine the migration rate for black marlin tagged 

 in September (9 fish recaptured), October (13 fish recaptured), 

 and November (3 fish recaptured). No black marlin tagged in 



11 



