FISHERY BULLETIN: VOL. 84, NO. 4 



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Figure 2.— Profiles of water temperature and salinity (November 1981-October 1982) at a representative station from the study area 

 located in neritic waters of the northern Gulf of Mexico off Louisiana. A. Water temperature, B. Salinity. X indicates sampling depths. 

 Collection dates were scaled by Julian calendar. 



larvae of clupeiform fishes; these were usually <10 

 mm SL. 



Generally, seasonal larval densities followed water 

 temperatures (T) and were lowest during winter (X 

 = 51/100 m 3 at T <20°C), increased during the 

 spring (X = 207/100_m 3 at T <25°C), peaked 

 during the summer (X = 394/100 m 3 at T near 

 30°C), and declined during the fall (X = 179/100 

 m 3 at rapidly declining T). Approximately 6% of all 

 fish larvae were collected during the winter and 

 47.5% during the summer. Larval densities were 

 lowest in December and highest in June, with a 

 mean monthly density of 208/100 m 3 (Fig. 3). Over- 

 all, December had the fewest taxa (13) and Septem- 



ber the most (37). Five families accounted for about 

 90% of total larvae: Engraulidae, Sciaenidae, 

 Clupeidae, Carangidae, and Bothidae. The five most 

 abundant taxa overall, in order of decreasing abun- 

 dance, were anchovies (Engraulidae); Atlantic 

 croaker, Micropogonias undulatus; Atlantic thread 

 herring, Opisthonema oglinum; gulf menhaden, 

 Brevoortia patronus; and Atlantic bumper, Chloro- 

 scombrus chrysurus. These taxa accounted for about 

 82% of all larvae taken. Thirty-eight taxa occurred 

 in sufficient numbers that they were within the 10 

 most abundant taxa collected in at least one month. 

 Densities of these taxa are presented in Table 1. 

 Anchovies accounted for about 49% of all larvae 



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