SHANKS: SHOREWARD LARVAL TRANSPORT 



Table 4— The density (mean no. /1 00 m^ + SE) of larval fish in front of the set of internal waves, the weighted 

 average over the internal waves, in the internal wave slick (convergence zone), the rippled water between slicks 

 (divergence zone), and behind the internal waves. Significance compares the density between these samples using 

 a Wilcoxon's two-sample test. J = Juvenile, LPF = Late Post Flexion, ERF = Early Post Flexion, F = Flexion, 

 PF = Preflexion, and Total = Sum of all stages. 



'Wilcoxon's two-sample test (Sokal and Rohlf 1969). * = P < 0.05. 



^Weighted average density over an internal wave assuming a 30 m wide slick and a 100 m wide ripples. Internal wave = [(slick 

 no./m2 X 30 m^) + (ripples no./m^ x 100 m2)/130 m^] x 100. 



In contrast, in tows from internal waves oriented 

 parallel to shore there were numerous instances in 

 which larval densities were significantly higher in 

 the slicks (Tables 1, 2, 4); the densities observed in 

 the slicks were 4- to >50-fold higher than those in 

 the rippled waters. These data demonstrate that a 

 variety of larval and postlarval invertebrates and 

 fish were transported shoreward by these internal 

 waves. 



On 24 June 1985, surface plankton samples were 

 collected in the first two slicks over a set of inter- 



nal waves oriented parallel to the shore, in the rip- 

 pled water between these slicks, and in front and 

 behind the entire set of internal waves. Ninety-six 

 percent of the surface drifters were caught by the 

 first two convergence zones and carried shoreward 

 about 4 km. The density of Sargassum floats was 

 highest in the slicks (>100-fold, Table 2) and they 

 were at significantly lower densities behind the set 

 of internal waves than in front. There were 0.9 

 Sargassum floats/100 m^ in the waters in front of 

 the set of internal waves and none in the waters 



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