ILLUSTRATIONS 



FIGURE Page 



Frontispiece: Diagram showing longline setting procedure from a tub aboard the 

 John R. Manning 



1. Comparison of yellowfin catch rates on steel and cotton gear and comparison of 



catch rates between two vessels fishing simultaneously in the same area. ... 3 



2. Catch rates for three size classes of yellowfin captured on cotton and steel longline 



gear on John R. Manning cruise Z4, 3 



3. Depth of various hooks on single baskets of longline, as determined by sounding 



tubes 4 



4. Latitudinal variation in depth of the deepest hooks on longline sets, as determined 



by sounding tubes, I57'48' W. - 161 "57' W. longitude, John R. Manning cruise 27, 

 October 1955. 5 



5. Variation in average depth of the deepest hooks on longline sets in relation to time 



of year, 1955-56 5 



6. Relationship of the average depth of the deepest hooks of longline sets and yellowfin 



catch rates 6 



7. Length frequency distributions of oceanic and insular yellowfin caught by longlining 



and trolling 7 



8. Yellowfin troll catch rates in the Line Islands arranged by time of day 9 



9. Yellowfin troll catch rates in the Line Islands March 1955 to February 1956 9 



10. Relationship of yellowfin troll catch rates to areas. Line Islands, March 1955 to 



February 1956 9 



11. Daily yellowfin longline catch rates in the Line Islands, 1955-56. 10 



