FISHERY BULLETIN: VOL. 79, NO. 4 



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Figure L — Search (squares) and drogue stations (inset) during the vertical distribution study of ichthyoplankton in the Middle 



Atlantic Bight, July 1974. 



m. Plankton was sampled near the drogue at 3-h 

 intervals for 72 h starting at 0600 (e.s.t.) on 18 

 July 1974. We used 20 cm bongo nets equipped 

 with General Oceanics^ flowmeters and 0.505 mm 

 mesh nets. This mesh size may have caused 

 extrusion of smaller larvae and eggs. Two or 

 four nets were fished simultaneously at discrete 

 depths. A Braincon 6-ft (1.82 m) V-fin depressor 

 was used and v^re stops held the nets at pre- 

 determined places on the wire. 



'Reference to trade names does not imply endorsement by the 

 National Marine Fisheries Service, NOAA. 



Before each tow, temperature profiles were ob- 

 tained with expendable bathythermographs and 

 surface salinity samples were taken. Before every 

 other haul salinity samples from the sampling 

 depths and 50 m were obtained. Salinities were 

 determined on shore with a Beckman RS 7B 

 induction salinometer. 



Nominal plankton sampling depths were: sur- 

 face, 2, 4, 6, 15, and 30 m. Every 3 h a haul was 

 made at 0, 4, 15, and 30 m (first experiment). 

 During the second half of the 72-h period, on every 

 other haul a second haul was made in a similar 

 manner immediately after the first one with the 



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