Table 2.— Summary of figh categories showing numbers caught 

 and seasons present — Continued. 



Total Number 

 number caught per Seasons 

 Category caught occurrence present 



rANGUILLIFORM LEPTOCEPHALI 



Hemiramphus brasiliensis and Hyporhamphus uni- 

 fasciatus, for example, were both more numerous and 

 larger in night tows than in day tows. Conversely the 

 round scad, Decapterus punctatus, and puffers of the 

 genus Sphoeroides were prevalent in day tows. The 

 accumulating effect of weed during all hours, 

 however, might modify the diel behavior of juvenile 

 fishes for day-night differences in the catch of most 

 species closely associated with sargassum were not ap- 

 parent. 



Although the larvae of many species were caught 

 during more than one cruise, if not throughout the 

 year, spawning which contributes young fishes to the 

 surface fauna of the South Atlantic Bight is at a max- 



MULLIDAE 



CORYPHAENIDAE 



Figure 2. — Familial constituents of total surface-towed, meter 

 net catch during 1967-68. 



imum in the spring and summer. Figures 7 through 10 

 show the seasonal diversity in larval and juvenile 

 ichthyofauna at the surface. During the winter (Fig. 

 10), the ranges of the few species occurring in inshore 

 surface waters (notably Urophycis regius, Mugil 

 cephalus, Mullus auratus, Leiostomus xanthurus and 

 unidentified sparid larvae) extend offshore and 

 overlap with the ranges of Gulf Stream inhabitants, 

 resulting in an area of increased variety over the mid- 

 dle shelf north of Cape Kennedy. 



Except for the obvious inshore species such as 

 Anchoa mitchilli and offshore species such as 

 istiophorids and exocoetids, lines between inshore and 

 offshore species are not clearly drawn. A more definite 

 separation exists between those species occurring 

 primarily in the Gulf Stream (Histrio histrio, and 

 some flyingfishes) and those ranging over the con- 

 tinental shelf. 



The average number of each species taken per 

 successful tow (Table 2) indicates that most of the 

 fishes caught had not yet begun to aggregate or at 

 least occurred in such low densities that large catches 

 were precluded. Schooling was apparent in very few 

 species (i.e., anchovies, silversides, scads, and butter- 

 fish). Possibly the protective value of schooling 

 (Breder 1967) is less necessary in surface waters where 

 weed or debris are available for cover. 



An area used as a nursery by developing fishes must 

 provide a food source, protection from predation, and 

 suitable hydrographic conditions. Both the Gulf 

 Stream, with its floating mats of sargassum, and in- 

 shore bays and estuaries fulfill the first two re- 

 quirements, but the two areas differ markedly in 



