RECORD OF STANDARDIZED HAUL FACTORS FOR OBLIQUE HAULS 

 MADE WITH PLANKTON NETS DURING CRUISES 5601-5612, 1956 



Standardized haul factors are given for all plankton hauls taken on 

 survey cruises during 1956, except those made in the Gulf of California 

 (table I). Additional information concerning each haul, including position 

 of occupancy, date and time of collection, volume of water strained, and 

 depth of haul in meters is given in Thrailkill, 1957 (Zooplankton volumes off 

 the Pacific coast, 1956). 



A standardized haul factor is used for adjusting counts of eggs and lar- 

 vae from a station to the number under 10 square meters of sea surface. This 

 estimate is a valid one, if the vertical distributions of the eggs or larvae 

 have been encompassed. As noted in the preceding report (Ahlstrom and Kramer 

 1957:4), this requirement has been met for all species included in this report 

 except hake larvae. It is estimated that about 10% of hake larvae occur below 

 140 meters, the average depth sampled in taking routine plankton hauls. 



The following symbols are used in table I: 



(-) - a dash indicates that the station was not occupied on the cruise 



under which it appears 

 NQ - plankton haul taken, but not considered quantitative 

 NS - station occupied, but sample subsequently spoiled, broken or lost. 



Six stations were occupied by two different vessels on cruise 5603, and 

 two stations were occupied twice on cruise 5606. The standard haul factors 

 for the second occupancy of the above eight stations are listed here, since 

 there is no space for' these factors in table I. 



Cruise Station S. Factor 



The standard haul factors for stations occupied in the Gulf of California 

 or on station lines below the Gulf (several lines of stations were occupied 

 to the south of the Gulf on cruise 5612) are not included in this report. 



