Criales and Lee: Larval distribution and transport of penaeoid shrimps 



477 



Early June 

 Late June 



Figure 3 



Percentages of the larval stages of pink shrimp, P. duorarum, at 

 the Tortugas and NW Patch transects during the four legs of the 

 cruise LH3, 29 May-30 June 1991. Z = zoeae; M = myses; and P 

 = postlarvae. 



Rebecca transect showed a similar trend to that de- 

 scribed for P. duorarum: a high concentration of zoeae 

 at the deployment of the drifter (80% zoeae) and 15 

 days later a dominance of myses (100% myses). 



Discussion 



Munro et al. ( 1968), in an examination of abundance 

 and distribution of P. duorarum larvae in southeast 

 Florida, could not reach firm conclusions regarding 

 the path of migration from the Dry Tortugas to 

 Florida Bay because of the inconsistency between the 

 prevailing currents and the abundance of larvae in 

 the pathway to the coast. However, they hypothesized 

 that P.- duorarum larvae may have been advected 

 from where they were spawned in the Tortugas 

 Grounds by means of the Florida Current and then 

 were carried back into Florida Bay by tidal currents 

 through passes in the middle Keys. The conceptual 

 path of larval advection outlined by Munro et al. 

 (1968) was consistent with the general current pat- 

 tern known at that time. More recent oceanographic 

 research on the Straits of Florida has shown a high 

 variability in the Florida Current in the lower Keys 

 and Dry Tortugas associated with meanders and 

 gyres (Lee et al., 1992, 1994). Lee et al. (1994) showed 

 from moored current meter data and surface drifter 

 tracks that a cold, cyclonic gyre formed off the Dry 

 Tortugas in mid-May and continued as a weak coun- 

 terclockwise recirculation about 200 km in diameter 



until late August. Thus, the presence of the gyre could 

 have acted as a larval retention and recirculation 

 mechanism for the duration of the sampling cruise. 

 Distributions of zoeae and myses of P. duorarum 

 found in this study agree with those of Munro et al. 

 (1968) and Jones et al. (1970) for the Tortugas shelf. 

 However, postlarval distribution in the present study 

 was different; most postlarvae (stages I— III) were lo- 

 cated inshore near the area where they were 

 spawned, rather than offshore as was found by Munro 

 et al (1968). Composition of larval stages at the 



