Althougli most of this work so I'ar has been de- 

 signed to control the quahty of tiie data, P.E. Smith has 

 made some preliminary analyses of them. He has gen- 

 erated long-term summaries of anchovy, sardine, and 

 saury eggs by region and by month. These long-term 

 averages permit iiim to assign relative confidence limits, 

 based on binomial probability, to the estimates each 

 month for all the available years. He has defined the 

 average spawning centers for each species to help him 

 design the extensive CalCOFI cmises planned for the 

 calendar year 1969. 



CalCOFI survey cruises have continued on a re- 

 duced basis during the past year in preparation for the 

 1%*-) sui'veys. The autumn 1%7 cruise was aborted be- 

 cause of vessel breakdown, but a summer 1967 cruise 

 was made by the SIO vessel Ellen B. Scripps ( 1 70 sta- 

 tions), a winter 1967-68 survey was made by Horizon 

 (216 stations), and a spring 1968 survey was made by 

 David Starr Jordan ( 194 stations). Data were collected 

 on these cruises from San Francisco south to Magdalena 

 Bay in Baja California. 



Pacific sardine ( 1951-59).-Dunng this period some 

 sardine spawning occurred in each month of the year in 

 Los Angeles Bight and Sebastian Vizcaino Bay, although 

 most spawning occurred during May, when eggs were 

 taken over an area of more than 75,000 square miles 

 (258,000 km.-). Long-term summaries showed a north- 

 ern and a southern spawning center. The southern area 

 had higher concentrations of eggs than the northern, 

 thougli this difference was probably a characteristic of 

 the decade following the decline of the northern sardine 

 subpopulation. 



A'c)/'//R'n;a/it7/oin'/'^957-59/— Most anchovy spawn- 

 ing occurs in February , March, and April in the California 

 Current but some takes place in all months; major spawn- 

 ing areas appear to be within 80 miles ( 148 km.) of the 

 coast; the total area over which eggs occurred varied from 

 67.000 square miles (230,000 km.-) in January and April 

 to 14,000 square miles (48,000 km.-) in October. A 

 number of separate spawning localities can be recognized 

 in the long-term averages. The Ensenada region shows a 

 single spawning peak during February; in Vizcaino Bay 

 spawning occurs in March; from the Los Angeles Bight to 

 San Diego, spawning is significant from February througli 

 June and outside the Channel Islands there is a single 

 spawning peak in April. These locations are reflected 

 both in the frequency of occurrences of eggs and in the 

 number of eggs in samples in wliich eggs occurred. 



Jack mackerel (195 1-60). -Most jack mackerel lar- 

 vae occur in the CalCOFI grid from March through June 

 though this grid does not sample the offshore nor the 

 northern extent of the spawning range of this species. 

 Most spawning appears to be more than 80 miles (148 

 km.) offshore, and the spawning region moves north- 



ward as the season progresses. 



Pacific mackerel (1951-60). -Pacific mackerel lar- 

 vae occur over the entire year within the CalCOFI grid, 

 but they have never been abundant and the grid does 

 not appear to reach the southern limit of spawning of 

 this species. 



Pacific hake (1955-59). Hake larvae appear in the 

 samples in December, reach maximum numbers in Feb- 

 ruary and maximum areal extent in March; spawning 

 after April is limited. Spawning extends from Cape San 

 Lucas to Central California, but the northern limit of the 

 spawning of this species has been identified in only some 

 years by the CalCOFI samples, which have usually un- 

 dersampled the northern area. 



DYNAMICS OF FISH POPULATIONS 



For more than 25 years BCF and California De- 

 partment of Fish and Game have had a cooperative pro- 

 gram for sampling and aging sardines, anchovies, jack 

 mackerel, and Pacific mackerel from the California Cur- 

 rent. This project is the Bureau contribution to this co- 

 operative research. During the year, arrangements were 

 made to bring the Mexican Federal Laboratory at EI 

 Sauzal, Baja California, into the sampling program; the 

 fisheries for these four species are coinmon to both 

 United States and Mexican waters, so a cooperative 

 program of sampling and data exchange has become 

 necessary. 



J.S. MacGregor continues to direct the Bureau 

 phase of the cooperative scale reading; work has been in 

 progress on reading the scales from the 1966-68 seasons. 

 J.S. MacGregor is also continuing his studies on the fe- 

 cundity of pelagic species and is analyzing a considerable 

 body of historical data on the development of the gonads 

 of the Pacific sardine in the California Current with re- 

 spect to year and area. This information, taken together 

 with the data on egg abundance and distribution, and 

 water temperatures corresponding to the years in which 

 the samples were taken will enable him to investigate the 

 relation between fecundity and the environmental varia- 

 bles and geographical areas. His studies on the fecundity 

 of the northern anchovy have been completed and are 

 being used for population estimates from the egg and 

 larva surveys. 



RACIAL STRUCTURE OF COMMERCIAL SPECIES 



A.M. Vrooman has continued his work on the sub- 

 populations of the northern anchovy. His results show at 

 least two genetically distinct subpopulations off the coast 

 of California and Baja California. Samples from these 

 two areas differ significantly in the frequency of three 

 genes which control six recognizable transferrin types. 



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