off the coast of Baja California indicated this population to be 

 similar to one of the two genetic populations of skipjack found 

 in the Hawaiian fishery. Recovery in the Hawaiian fishery of 

 a skipjack that had been tagged off southern California pro- 

 vided substantiating evidence that skipjack of the eastern Pa- 

 cific are intimately related to those appearing in the Hawaiian 

 fishery. 



A model on the origin of the exploited stocks of skipjack 

 in the central and eastern Pacific was formulated. It incor- 

 porates the hypothesis that a large component of the species 

 appearing in the eastern Pacific and Hawaiian skipjack fisher- 

 ies originates in the central equatorial Pacific. 



A summary of bird flock and fish school sightings col- 

 lected over a 10-year period was completed. Since aggrega- 

 tions of sea birds in the open sea, especially when feeding, 

 are generally associated with schools of fish, these data are 

 useful indicators of the distribution of surface schools of pe- 

 lagic fishes. 



Ecological studies of albaoore tuna were continued. Two 

 cruises into the South Pacific Ocean indicated that the albacore 

 spawning period in the South Pacific occurs in December and 

 January. These spawning data and discovery of juvenile alba- 

 core in stomachs of predators captured at widely scattered 

 points in the North and South Pacific were evidence that the 

 albacore from the North and South Pacific constitute separate 

 subpopulations, also that spawning occurs in a broad area in 

 the North Pacific and in the South Pacific. The identification 

 of juvenile albacore was simplified by the unique shape of the 

 first elongate haemal spine of the species, a definitive charac- 

 ter present in both the juvenile and adult albacore. 



The critical question of the identification and location of 

 subpopulations has been attacked by a variety of methods, one 

 of these being the use of serological techniques. In this field, 

 the Laboratory has made two important contributions to knowl- 

 edge of tuna subpopulations--the discovery of a blood-group 

 system in bigeye tuna similar to the familiar A-B-O system 

 in man, and the definition of several skipjack subpopulations 

 in the Pacific. 



Research programs relating to the physical and chemical 

 environment of the Pacific Ocean covered a wide array of prob- 

 lems. Compilation continued of Pacific-wide oceanographic 

 station data, such as temperature, salinity, and oxygen. When 

 completed, the data will provide information on the mean dis- 

 tribution of these parameters over broad areas of the Pacific, 

 give a general view of the seasonal changes of these proper- 

 ties, and present some of the features of the currents through- 

 out the Pacific. On a more limited areal scale, study began 

 of the effects of the Hawaiian Islands on circulation patterns 

 and on physical properties of the waters. The two-pronged 

 approach to the problem included directly observing ocean 

 currents by releasing drift cards at sea and using a topographic 

 scale model of the Hawaiian Islands chain to evaluate some of 

 the theoretical aspects of the circulation. 



One of this Laboratory's special studies, the Indian Ocean 

 Program--a part of the U. S. Program in Biology of the Inter- 

 national Indian Ocean Expedition--was designed to study the 

 biology of that area's large pelagic fishes and to explore the 

 shelf areas of the Arabian Sea and the Bay of Bengal for benthic 

 fishes and shellfishes. Objectives of these studies were to 

 add to the scientific knowledge of these little-known waters 

 and to indicate their potential protein resources for neighbor- 

 ing peoples. Our surveys revealed the presence of a variety 

 of species of fish and shellfish, but we made few catches of 

 pelagic fish in commercial quantities and encountered no new 

 commercially important trawling ground. 



It has been apparent for several years that the Labora- 

 tory's single research vessel, the Charles H. Gilbert , could 

 not meet the increasing demands for more ship's time to col- 

 lect data in the field. Inl962, the Congress appropriated funds 

 for the construction of a new oceanographic research vessel 

 for use in the Hawaiian area and the new ship, the Townsend 

 Cromwell , was completed in November 1963. The Cromwell 

 is one of the Nation's most modern oceanographic research 

 vessels and is designed and outfitted to perform many types of 

 oceanographic and biological work. 



A significant innovation in the ship's design is a bulblike 

 projection below the waterline on the bow. It significantly in- 

 creases vessel efficiency by reducing the intensity of bow 



