FISHERY BULLETIN: VOL. 85, NO. 3 



Table 4. — Species composition of zooplankton samples from the vertical distribution stations. 



Taxon 



Number 

 (See Fig. 11) 



Name 



Maximum 

 No./IO m3 



Minimum 

 No./IO m3 



Pseudocalanus spp. adult female 



Pseudocalanus spp. adult male 



Pseudocalanus spp. copepodids 1-5 



Neocalanus spp. and Calanus spp. 



Oithona spp. 



Acartia spp. 



Centropages spp. 



Metridia spp. 



Eucalanus bungli 



Paracalanus sp. 



Clausocalanus sp. 



Torianus spp. 



Unidentified calanoid 



Euphausiid furcilia 



Euphauslid calyptopsis 



Euphausiid crytopsis 



Thysanoessa Inermis furcilia 



T. inermis calyptopsis 



T. inermis crytopsis 



Euphausiid juveniles 



T. inermis juvenile 



Chaetognatha 



Appendicularia 



Hypendae 



Gastropoda 



Decapoda 



Balanidae 



Gammaridae 



Evadne spp. 



Limacina spp. 



Pontellidae 



Thecosomata 



Brachyura 



Gymnocomata 



Echinodermata 



Hydrozoa 



Pelecypoda 



Medusa 



Siphonophore 



Mean 

 No./IO m3 



1 

 2 

 3 



4 

 5 



6 



7 

 8 

 9 

 10 

 11 

 12 

 13 

 14 

 15 

 16 

 17 

 18 

 19 

 20 

 21 

 22 

 23 

 24 

 25 

 26 

 27 

 28 

 29 

 30 

 31 

 32 

 33 

 34 

 35 

 36 

 37 

 38 

 39 



eluded N. plumchrus , C. pacificus, and C. mar- 

 shal lae. Together these species contributed be- 

 tween 13 and 259r of the total zooplankton 

 (Fig. 12). 



Euphausiids were the only other abundant 

 group of zooplankters; furcillae were the most 

 abundant stage. The abundance of furcillae was 

 generally <200 m ■^; however, at 1047 h on 29 

 May, the numbers of furcillae exceeded 1,300 



m 



-3 



Age and Growth 



Ages were determined for 109 walleye pollock 

 larvae, including 40 individuals collected from 

 Station 37 within the area of highest larval abun- 

 dance and 69 specimens from four stations well 

 removed from this area. Standard lengths ranged 

 from 6.0 to 14.6 mm and mean increment counts 



(days since hatching) ranged from 7 to 45.5 

 (Table 5). The average gi'owth rate varied from 

 0.12 to 0.25 mm/day among the five stations 

 (Table 5). When compared pairwise with growth 

 rates from all other stations, growth rates from 

 all stations located outside the dense patch, ex- 



Table 5. — Average growth rates, statistics on the linear regression, 

 comparison lengths, and ages of larval walleye pollock used in 

 growth analysis from five areas in the Shelikof Strait. Station 37 is 

 in the area of highest larval density (Fig. 1). 



37 37 0.24 0.82 40 40 6.8-13.1 12-42 



53 4.2 0.23 0.81 20 20 7.6-13.0 20-41 



9 3.5 0.25 0.81 20 20 6.0-14.6 7-43 



6 4.7 0.18 0.61 20 20 6.6-12.3 10.6-42.2 



12 6.6 0.12 0.90 9 9 8.1-12.6 14-45.5 



514 



