taken in sets, in lots of 1 to 29; however, there seemed to be no connection be- 

 tween jack mackerel and numbers of tuna caught. 



Condition of Gill-net Fish 



Three factors found to affect the condition of albacore taken by nets are: 



(1) The pattern in which the fish swim into the nets. 



(2) The force of wind and state of sea during hauling of the nets. 



(3) The length of tin:e the fish are in the nets. 



Most of the albacore taken in gill nets were caught near the surface and 

 in small, scattered groups, quite often intermingled with the pomfret and jack 

 mackerelo Especially was this bunching tendency noted on July 31j at 46° 31' N, 

 latitude and 130° 55' W. longitude, where the nets picked up 8 albacore and 2 blue 

 shark. The albacore were all in one bunch in the Y^-inch linen web. Again off the 

 Queen Charlottes on August 19, where 169 albacore and an estimated 150 pomfret were 

 taken, the albacore were scattered at intervals with the pomfrets in bunches through 

 the entire net. One of these clusters of fish necessitated hauling a section of 

 the net on deck to remove the fish. 



Wind force was a major problem in gill netting as the large super-struc- 

 ture of the Cobb lessened her ability to maneuver in a strong wind and caused con- 

 siderable strain on the nets at times. Two types of injuries to albacore were 

 noted in the gill-netting operation. These were injuries to the tail portion of 

 fish, and bruises and cuts caused by varying amounts of tension on the meshes of 

 the nets; a few fish v/ere also damaged by sharks. Of the 251 albacore taken in gill 

 nets, approximately 6U, or about 25 percent, were damaged by either having broken 

 tails or cuts and bruises. The former condition was more common, and was possibly 

 easier to notice, The broken tails were believed to be due partly to the narrow 

 hauling sheave through which the fish had to- pass when being brought up over the 

 rail, a condition which might be remedied by using a larger roller. Different de- 

 grees of broken or damaged tails were noted on 45 fish, or about 70 percent of 

 those that were damaged. 



Table 4 shows the number and kinds of injuries to the tuna caught in the 

 nets on August 19. 



Table 4. — Injuries to gill-net fish August 19. 1950 



An important factor undoubtedly affecting the condition of gill-net-caught 

 albacore is the length of time they are in the nets before being hauled aboard. Es- 

 pecially in warmer waters would this be true, as the fish tend to become soft and 

 easily damaged after soaking for several hours. As all the night sets were of 7 to 

 11 hours' duration, and it was not possible to determine at what time the tuna swam 

 into the nets, no comparison concerning time in the water can be made. But it is 

 possible that sets of only a few hours would yield fish which would be less subject 

 to damage from the gear. 



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