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FISHERY BULLETIN: VOL. 70, NO. 4 



Table 12. — Relative abundance and percentage contribution of fish larvae of the 10 most common families within 

 that portion of EASTROPAC area covered on six successive bimonthly cruises between February 1967 and Jan- 

 uary 1968. 



1 ETP I -stations 11.022-11.118 (35), 

 a ETP II - stations 45.016-45.114 (41), 



12.002-12.109 (50), 12.209-12.264 (24), and 13.187-13.265 (28), 

 45.191-45.365 (37), 46.002-46.069 (36), and 46.079-46.132 (27). 



in all cruises. The average abundance per haul 

 ranged from 9.5 larvae (June-July) to 17.1 

 (April-May), a range of less than two times. 



Bathylagid smelts were represented in the 

 monitoring pattern by a single species, Bathyl- 

 agus nigrigenys Parr. Average abundance of 

 larvae per haul ranged from 2.6 (December- 

 January) to 6.4 (February-March) and aver- 

 aged 4.0 larvae. Larvae of Bathylagidae usually 

 ranked fifth in abundance. 



Paralepididae usually ranked fourth in rela- 

 tive abundance; the lowest average abundance 

 per haul was 3.2 larvae in October-November, 

 and the highest was 8.2 larvae in August-Sep- 

 tember. 



Nomeidae ranked variously fifth to eighth in 

 relative abundance, with an overall ranking of 

 sixth. The range in average abundance per 

 haul was from 1.5 (October-November) to 5.1 

 larvae (June-July) and averaged 3.4 larvae. 



Bregmacerotidae showed the widest variation 

 in abundance, 1.3 larvae (April-May) to 6.6 lar- 

 vae (February-March); consequently they 

 ranked variously between fourth and tenth in 

 relative abundance. Larvae of the most com- 

 mon species of Bregmaceros within the monitor- 

 ing pattern, B. hathy master, tend to cluster with 

 occasional samples having rather large numbers 

 of larvae. Variability in sampling due to chance 

 encounters of clusters of larvae could be of 



greater magnitude than that resulting from ac- 

 tual changes in reproductive activity during the 

 year. 



Idiacanthidae, usually ranked eighth in 

 abundance per haul from 1.1 (October-Novem- 

 ber) to 2.9 larvae (April-May), with an overall 

 average of 2.2 larvae per haul. 



Melamphaidae ranked variously between sev- 

 enth and tenth, with an overall rank of ninth. 

 The lowest abundance, 1.3 larvae per haul in 

 December-January, was less than half the high- 

 est, 2.9 larvae in August-September. 



Scombridae in the monitoring area ranked 

 either ninth or tenth in relative abundance of 

 larvae on all cruises; the lowest average abun- 

 dance, 0.6 larvae per haul in August-September, 

 is only a fourth of the highest average value, 2.4 

 larvae in February-March. 



Larvae of these 10 families made up over 92% 

 of the fish larvae in the monitoring pattern. In 

 all instances, larvae of all principal families 

 were taken throughout the year. The spread 

 between the highest and lowest abundance val- 

 ues for larvae of these principal families of fish- 

 es was usually less than three times, and for 

 Myctophidae and Sternoptychidae, was less than 

 double. 



A similar seasonal pattern of abundance was 

 observed for individual genera or species (Table 

 13). I found it helpful to arrange the 18 ge- 



1168 



