half the total amount of netc Ihe total hours spent in fishing by 

 both vessels wa'? 29U, with a total of 196 shackles set.. The catch 

 per unit of effort was Ool3 fish including OU tunas per shacklec. 

 but if allowance is made for half of the mesh being too large, the 

 catch per shackle is double that indicatedo 



Several factors affected the fishing operations., the most 

 noticeable of which were wind,, current, and sea conditLonso Although 

 the upper limits of these factors were not investigated thoroughly <■ 

 it was possible to fish with the wind velocity up to 30 kno&So TUB-nds 

 of this force caused heavy strain on the gear and e^ecially on the 

 line by which the net was secured to the vessels The strain was 

 somewhat reduced by the addition of more line; 



Strong currents were a cons^ant source of concerns Although 

 the net was usually set across or obliquely to the direction of the 

 cxrrrent, it often swung arcund to a position parallel to the current 

 during xho set-. In localities where ths corrent changed its direction 

 of flow several times during the night j the net folded upon itself ^ 

 thus pressiting only a part of its laigth to actuail fishingc. Drifting 

 over 15 miles during the night was not uncommon^ and in several 

 instances where the current was extremely rapid^ the net drifted into 

 the wind e^^-en though the wind velocity exceeded 28 knots. Tne current 

 also affected the vertical angle of the neto During one of the 

 cross=current sets, a current of approximately 1/2 knot caused the 

 net to fish at a 35=^0 degree angle with the s^^rface. This was prob- 

 ably due to the shear between the surface and the lower water layer j 

 or to the effect of the wind acting on the floats in a direction 

 opposite to the ciKrentg or possibly to a combination of bothc 

 However, the velocity of the wind was only about 10 knots on this 

 particular seto 



Sea conditions affected the retrieving operation greatly^ Ihe 

 ship's roll, due to large swells j caused great strain on the net, 

 and often this resulted in nuaierous tears in the webbing alcng the 

 lead arrL float lines , The Manrang worked in swells up to 7 feet in 

 height, A smaller vessel probably could have performed this operation 

 in much rougher water with less damage to the gear^ It was evident 

 from the first few sets that the net could only fish safely from the 

 Manning in areas of calm water o 



FiaiING (SOUNDS AND SEASCWS 



The observations made on the fishing areas showed that in the 

 Hawaiian Islands caJa waters are found only in the leeward areas of 

 the islands cf Hawaii, Oahu,- and Kauai o ttily at twc islands.; Hawaii 

 and Oahu^ dees this lee extend much beyond 15 miles from shore » At 

 Kauai it extends only L cr 5 mileSo Ihe lee at Mauij, although it is 



Ih 



