Zooplankton Volumes Off the Pacific Coast, 1960 



By 



JAMES R. THRAILKILL, Fishery Biologist 



Bureau of Commercial Fisheries 



Fishery-Oceanography Center 



La Jolla, Calif, 92037 



ABSTRACT 



Basic data on volumes of zooplankton are given, together with data for all 

 plankton hauls taken on survey cruises of the California Cooperative Oceanic 

 Fisheries Investigations. Distribution charts showing relative areal zooplankton 

 abundance by month are included. 



Reports on zooplankton volumes obtained on 

 cruises by CalCOFI (California Cooperative 

 Oceanic Fisheries Investigations) off the Pa- 

 cific coast have been published annually since 

 1949. Six reports in this series, for 7 years 

 (1949-55), contained basic data on the volumes 

 of zooplankton collected on monthly survey 

 cruises (Staff, South Pacific Fishery Investi- 

 gations, 1952, 1953. 1954a, 1954b, 1955). Four 

 reports, for 1956-59, contained monthly dis- 

 tribution charts in addition to the basic data 

 (Thrailkill, 1957, 1959, 1961, 1963). Thrailkill 

 (1956) illustrated the relative areal zooplank- 

 ton abundance in monthly and yearly distribu- 

 tions for 1949-55. 



Zooplankton volumes in the California Cur- 

 rent system in relation to the rest of the Pa- 

 cific Ocean were compiled by Reid (1962). 



The CalCOFI program is sponsored by the 

 Marine Research Committee and carried out 

 cooperatively by the Scripps Institution of 

 Oceanography of the University of California 



San Diego, the Pelagic Fish Investigations of 

 the California Department of Fish and Game, 

 the California Academy of Sciences, the Hop- 

 kins Marine Station of Stanford University, 

 and the Fishery-Oceanography Center of the 

 Bureau of Commercial Fisheries. 



The Bureau uses the plankton samples pri- 

 marily for studies of the early life history, 

 distribution, abundance, and survival of com- 

 mercially important or potentially important 

 fishes. These collections are also used by the 

 Scripps Institution of Oceanography in studies 

 of productivity and zoogeography. 



The vessels used, and the CalCOFI cruises 

 for 1960, are given in table 1. Four vessels 

 were operated by the Scripps Institution of 

 Oceanography and one by the Bureau of Com- 

 mercial Fisheries. The stations occupied dur- 

 ing 1960 are shown in figure 1. The survey 

 cruises for 1960 and the areas covered and 

 the number of stations occupied each month 

 are given in table 2. 



Table 1. — Research vessels participating in CalCOFI Survey Cruises, 1960 



