784 



Fishery Bulletin 101(4) 



#h.n ^JT^ 



200 

 Estimated Spawning date 



300 



400 



78 

 Longitude (°W) 



40 



30- 



20 



10 





 16 



Southeast US 



iifn iMilniiFl] [1 



12- 



South Florida 





 60r 



50- 



40 



30 



20 



10 





 25r 



20 



15 



10 



5 





 12 



10 



8 



6 



4 



k 



Northcentral Gulf of Mexico 



iJIL.^ r 



Z 

 c 

 3 



Western Gulf of Mexico 







Eastern Caribbean 



100 200 300 400 



Estimated 

 spawning date 



Figure 5 



Estimated spawning dates (day of the year) for swordfish larvae collected from the Caribbean Sea, the Gulf of 

 Mexico, and off the southeast coast of the United States (hatched bars and circles depict winter in the north- 

 ern hemisphere, filled bars and triangles spring-summer, and cross-hatched bars and squares summer-fall): 

 (A) number of larvae and estimated spawning dates; (B) geographical distribution of larval collections; 

 (C) number of larvae and estimated spawning date by region; (D) number of larvae by region and season. 



rate oflarval blue marlin over the first 100 days or <10G0 

 mm LJFL (Prince et al., 1991). 



Larval and juvenile swordfish from the western North 

 Atlantic and Mediterranean exhibit four growth phases. 

 Growth is linear for larvae <11 mm PSL, for larvae 11 to 

 115 PSL, and for juveniles 510 to 740 mm LJFL (Megalo- 

 fonou et al., 1995). Growth becomes allometric for larger 

 juveniles (Ehrhardt, 1992). Larvae <11 mm grow -0.1 mm 

 LJFL/d. After the acceleration of growth, larvae in the 

 western North Atlantic grow at -3 mm LJFL/d, whereas 

 young juveniles in the Mediterranean grow at 23 mm 

 LJFL/d (Megalofonou et al., 1995). Growth slows in older 

 juveniles <250 mm LJFL to -2.5 mm LJFL/d (Ehrhardt, 

 1992). Adult growth (Berkeley and Houdc, 1983; Tserpes 



and Tsimenides, 1989) may constitute a fifth phase, as rec- 

 ognized by Yabe et al. (1959) for Pacific swordfish. 



The limited diet oflarval swordfish is unusual; few larval 

 fishes prey almost exclusively upon either copepods or lar- 

 val fishes. Swordfish larvae 12.0 mm total length (TL) eat 

 zooplankton, and larger larvae >12.0 mm TL eat other fish 

 larvae (Gorbunova and Lipskaya, 1975), including conspe- 

 cifics (Arata, 1954). Larval fishes as a whole are selective 

 feeders; Corycaeus is selected by larval percoids in the Gulf 

 of Mexico (Govoni et al., 1986b). Young larval istiophorids 

 from the Florida Current eat primarily cyclopoid copepods 

 of the genera Corycaeus, Farranula, and Oithona (Post et 

 al, 1997), before they become piscivorous (Gorbunova and 

 Lipskaya, 1975). Closely related genera of fishes exhibit 



