31 



72% of the populatioHo The remaining diatoms were Coscinodiscus 

 spo and Rhizosolenia sp<, Zooplankton were next in abundance 

 (15% of each net haul), and of the zooplankton, nauplius larvae 

 constituted t% of the population. 



High plankton numbers remained in the waters of Santa 

 Monica Bay and the Orange County coast through the months of 

 June and July. In the latter part of May and in the months of 

 June and July, though, dinoflagellates made up the bulk of the 

 population. During this period, the dinoflagellates constituted 

 66% of the total, with Ceratium tripos the most abundant form 

 (30%) o The dinoflagellate Peridinium sp. represented 18% of 

 each net haul, and the remaining dinoflagellates were other 

 species of Ceratium a The diatoms during this period represented 

 only 127o of the total population, whereas zooplankton repre- 

 sented 21%o This trend followed through June until in July, 

 the dinoflagellates made up 737o of the total plankton. In this 

 month, the dinoflagellate Ceratium fusus was the most common, 

 comprising 33% of each net haul. Diatoms were more abundant 

 than zooplankton (16%) and Chaetoceros sp. represented 15% of 

 the population. 



Ocean Conditions 



Temperature 



In the winter months, surface temperatures ranged from 

 a low of 55, 40F near Hyperion to a high of 57. 9°? near Orange 

 County, At these two outfalls the water was nearly isothermal, 

 there being a 2 to 30F range from 55 feet to the surface. 

 Near the Whites Point outfall the surface temperatures were 



