68 



Fishery Bulletin 104(1) 



Offshore mooring Maximum distance traveled in 

 the cross-shelf direction reached 60 km eastward and 

 80% of larvae traveled less than 30 km. Distances re- 

 corded in the alongshore direction were as far as 40 

 km northward (51%) and 40 km southward (49%) (Fig. 

 6, C and D). 



Scenario 3 Under the assumption that pink shrimp 

 larvae and postlarvae migrate vertically in a tidal cycle, 

 the third simulation postulates that larvae and post- 

 larvae swim in the water column near the surface at 

 night during the flood tide and remain near the bottom 

 during the ebb tide. In this simulation it is assumed 

 that planktonic stages move by using the eastward cur- 



Table 4 



Correlation coefficients of wind and current components. 

 U and V are the east-west and north-south components 

 respectively. Nearsurface currents are from onshore (A) 

 and offshore (B) ADCP moorings over the SW Florida 

 shelf Wind data are from Long Key CMAN station. Signif- 

 icant correlations (P<0.05l are indicated with an asterisk. 



Mooring A 



Mooring B 



onshore 



offshore 



[/-current V-current f7-current V-current 



{/-wind 

 V-wind 



-0.25* 

 0.26* 



-0.22* 

 0.55* 



-0.10 

 0.12 



-0.06 

 0.60* 



rent (flood tide) during the postulated 30 days of larval 

 development. 



Onshore mooring The maximum distance traveled in 

 the cross-shelf direction was 200 km eastward and 86% 

 of the larvae exceeded 150 km. The average eastward 

 distance in all simulations was 132 km. The maxi- 

 mum larval displacement occurred from December 1999 

 through March 2000. Distance traveled in the along- 

 shore direction was 45 km northward (70%) and 5 km 

 southward (30%) (Fig. 6, A and B). 



Offshore mooring The maximum larval displace- 

 ment in the cross-shelf direction was 200 km eastward 

 and 85% of the larvae reached 150 km. The maximum 

 eastward displacement occurred in fall and in winter. 

 Distance traveled in the alongshore direction was as 

 much as 40 km northward (82%) and 5 km southward 

 (18%). The maximum distance traveled was recorded in 

 March-April and June 2000 (Fig. 6, C and D). 



Scenario 4 In this simulation, it is assumed that there 

 is a change in behavior for pink shrimp larvae — an 

 assumption similar to the one taken in simulations for 

 some Australian penaeid species (Rothlisberg, 1982; 

 Rothlisberg et al., 1995, 1996). Early larval stages (pro- 

 tozoea and myses) migrate vertically in a diel cycle and 

 there is no cross-shelf displacement during the first 15 

 days of development. Later in development, postlarvae 

 migrate by using tidally induced behavior superim- 

 posed on the diel behavior for the remaining 15 days 

 of planktonic development, and the eastward current 

 (flood tide). 



Onshore mooring The maximum displacement of 

 larvae in the cross-shelf direction was 100 km eastward 



