Figure 13. — Launching 1/2- and 1-m nets to begin standard CalCOFI 



plankton tow. 



f . The net (s) is brought directly out of the 

 water at a steady rate. When the flow- 

 meter (s) breaks the surface the watch is 

 stopped. Its reading is the towing time 

 (item 9). 

 The net(s) is rinsed to get all the plankton 

 into the cod end, keeping the cod end(s) 

 dangling and the net ring(s) at rail height 

 (Fig. 15). The net(s) is brought aboard 

 (Fig. 6), and the cod end(s) removed, 

 keeping the plankton sample (s) from spil- 

 ling back into the net(s) . The plankton is 

 preserved immediately. 



10. 



The plankton is poured from the cod end 

 into a jar of appropriate size, usually a 

 quart. The cod end is rinsed down to gather 

 the last of the plankton at its bottom. When 

 fairly well drained, the cod end is everted 

 over and into the jar, and the remaining 

 plankton washed ofl? carefully. 

 The preservative (50 ml full-strength for- 

 maldehyde per quart) is added (see note 

 below) when the jar is at least three- 

 fourths full of seawater plus plankton in 

 order to avoid "burning" the delicate plank- 

 tonic organisms. Buffer to counteract the 



15 



