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Fishery Bulletin 93(2). 1995 



most abundant species by far was the hexagrammid 

 Hexagrammos decagrammus , which was present in 

 71% of all the samples collected and had a mean den- 

 sity of 234 larvae/1,000 m 3 (Table 3). Less abundant 

 were the hexagrammids H. stelleri and Pleurogram- 

 mus monopterygius. The category Hexagrammos spp. 

 was also numerically important. Many of these lar- 

 vae were most likely H. decagrammus, but the con- 

 dition of the specimens made specific identification 

 impossible. The most important taxa among the 

 cottids were Hemilepidotus hemilepidotus, H. 

 jordani, H. spinosus, Hemilepidotus spp., and 

 Myoxocephalus spp. Hemilepidotus hemilepidotus 

 was the third most abundant species overall, present 

 in 20% of the samples with a mean density of 60 lar- 

 vae/1,000 m 3 . Ammodytes hexapterus was the sec- 

 ond most abundant taxon with a mean density of 148 

 larvae/1,000 m 3 and was present in 14% of the 

 samples. With a mean density of 43 larvae/1,000 m 3 , 

 Cryptacanthodes aleutensis was ranked as the fourth 

 most abundant larval taxon and it was present in 

 21% of the samples collected. The remaining larval 

 taxa each were found in less than 10%- of the samples 

 and had a mean density of less than 20 larvae/1,000 

 m 3 . Most important among these were Mallotus 

 villosus, Theragra chalcogramma, the hexagrammids 

 and cottids mentioned above, Bathy master spp., and 

 the family Stichaeidae. The rest were scarce, mostly 

 with a mean density of less than 1 larva/1,000 m 3 

 and a percent occurrence of less than 2%. 



A comparison of the occurrence of dominant taxa 

 of ichthyoplankton in the neuston samples with their 

 occurrence in bongo samples, and estimates of the 

 fraction of each taxon in the neuston, indicate that 

 most of the dominant larval taxa in the neuston were 

 scarce or absent in the subsurface zone (Table 4). In 

 contrast, the dominant taxa of eggs were the same 

 for both neuston and subsurface samples. Theragra 

 chalcogramma eggs were by far the most abundant 

 and accounted for 69%- of all eggs caught in the neus- 

 ton and 95% in the bongo samples. Eggs of pleuro- 

 nectids, mainly of Microstomus pacificus, Hippo- 

 glossoides elassodon, and Errex zachirus, were the 

 only other eggs to be significantly abundant in ei- 

 ther gear, again indicating the paucity of pelagic 

 spawners in this region. The estimated fractions ( 6) 

 of these eggs occurring in the neuston were moder- 

 ately high (9-26%) merely showing that positively 

 buoyant eggs tend to accumulate in the surface layer. 



The only taxa of larvae well represented in both 

 neuston and bongo samples were T chalcogramma, 

 A. hexapterus, and Bathy master spp. (Table 4). All 

 three occurred in much fewer of the neuston net than 

 the bongo net samples, however. In addition, the frac- 

 tions of these taxa occurring in the neuston were low 

 (<13%) suggesting that they were only occasionally 

 abundant in the neuston. Among the less abundant 

 taxa in the neuston, Mallotus villosus, Stichaeidae, 

 Zaprora silenus, and Myoxocephalus spp. were only 

 slightly better represented in neuston net than in 



