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Fishery Bulletin 93(3), 1995 



thermocline (Fig. 5). The inshore distribution of 

 Solenocera sp. during this leg was noteworthy be- 

 cause these larvae showed an offshore distribution 

 during the other legs. 



High larval concentrations of the three species (P. 

 duorarum: 1-40 larvae/100 m 3 ; Sicyonia sp.: 1-22 

 larvae/100 m 3 ; and Solenocera sp.: 10-60 larvae/100 

 m 3 ) were found at the Tortugas transect during leg 2 

 in early June within and above the sea- 

 sonal thermocline between 25 and 75 m 

 in depth (Figs. 5 and 6). Total abun- 

 dances during leg 2 were much higher 

 than those during any other leg for all 

 three species. The abundance of Solen- 

 ocera sp. was twice as great during leg 

 2, and there were highly significant dif- 

 ferences among legs (ANOVA, P<0.05) 

 (Fig. 6). 



Drifter circulation Drifter Halley, de- 

 ployed on 30 May on the northern side 

 of the Tortugas Gyre, moved south- 

 southeast for about seven days, then 

 turned back toward the west-northwest 

 for about seven days (Fig. 7). The drifter 

 spent the first 14 days in a tight recir- 

 culation in the interior of the gyre. The 

 position of the drifter upon release ini- 

 tially corresponded with the position of 

 stations 26 and 27. On 13 June, when it 

 broke out of the gyral circulation, the 

 drifter was located at Rebecca transect 

 at station 56. At this point the drifter 

 entered the Rebecca Channel between 

 the Dry Tortugas and Rebecca Shoal 

 where it stayed for about 10 days, un- 

 dergoing tidal excursions of up to 7 km, 

 but with no net through-flow. Relative 

 percentages of the larval stages of P. 

 duorarum at the station where the 

 Halley drifter was released (Stns. 26 and 

 27) and at the station where this drifter 

 broke out of the gyre circulation (Stn. 

 56) are plotted in Figure 7. On 30 May 

 at stations 26 and 27, P. duorarum lar- 

 vae showed one mode of zoeae, mainly 

 II-III (84%). After 15 days, on 13 June, 

 one mode of postlarvae I (67.7%) was 

 present at station 56, a station near the 

 departure point. The trajectory of the 

 drifter Halley and the progression of age 

 of P. duorarum larvae over the 15 days 

 that the drifter spent recirculating 

 within the gyre may indicate retention 

 of P. duorarum larvae at the spawning 

 area. 



Abundance and composition of Sicyonia 

 sp. larvae at the same two locations, 

 stations 26 and 27, and at station 56 of 



