Moser and Pommeranz: Distribution of eggs and larvae of Engraulis mordax 



939 



A 



" 40-80 



E 



i= 80-120 



O 120-160 



o 



n 



ID 



Larvae/ 1000m3 



29 32 35 38 41 44 47 50 53 56 59 62 



0-40 ^ 



-E 40-80 



E 



2 80-120 



p. 120-160 



(1) 



D 



\'>,^^^^^^^^v ^:A^ 



28 31 34 37 40 43 46 49 52 55 58 61 

 30 33 36 39 42 45 48 51 54 57 60 63 



Tow number „ 



0-0 16 

 0-10 



}■-•-■ • • -• •■•-• •■' •! 



10-20 § 



20-30 

 30^0 

 40-50 



 '   '  1 



^ 



I I I \ 1 1 1 1 1— I 



12 3 4 5 6 7 8 9 5 10 15 20 25 30 35 40 45 50 



Larvae/ 1000m3 



Figure 19 



Citharichthys spp. larvae (no./lOOO mJ) in MESSHAI tows. Average from (A) deep and (B) shal- 

 low tows at inshore (solid) and offshore (shaded) stations; (C) densities in 0-80 m stratum (aver- 

 age of pooled 40-m strata) from sequential deep tows at inshore station; (D) densities in 0-40 m 

 strata (average of pooled 10-m strata) from sequential shallow tows at inshore station; average 

 from (El deep and (F) shallow tows at inshore station before storm (cross-hatching) and after 

 storm (hatching). 



neustonic zone (Ahlstrom, 1959; Moser and Boehlert, 

 1991). This distribution is clearly shown by comparing 

 the stratum of highest density at the inshore and off- 

 shore stations. Likewise, Pacific hake are broadly dis- 

 tributed over the shelf and slope and have deep-living 

 larvae (Ahlstrom, 1959; Mullin and Cass-Calay, 1997). 

 In our study, hake larvae were absent from samples 

 above 50 m depth at the offshore station. 



A comparison of larval anchovy length distribu- 

 tions from MESSHAI, bongo, and Manta net tows 



shows that the MESSHAI is less effective in catch- 

 ing larvae over 3 mm than the other two (Fig. 10, 

 A-C). The mouth opening of the MESSHAI net is 

 relatively much smaller (25x25 cm) than that of the 

 bongo net ( 7 1 cm diameter). Why the Manta net cap- 

 tures larger larvae is conjectural. It may be related 

 to the absence of an upward escape plane for larvae 

 in the path of the net or it may reflect the size fre- 

 quency of larvae in the surface layer. The bimodal 

 length distribution for anchovy captured in Manta 



