FISHERY BULLETIN: VOL. 84, NO. 1 



Figure 3— Minimum and maximum depth 

 of capture, with minimum, maximum, and 

 modal temperatures of capture for each 

 species and each cruise 



Table 1.— The coefficient of determination (r 2 ) for the change in 

 head length with change in depth regression lines. 



tributed to sampling artifacts and the relatively nar- 

 row depth range (674 m) of this species. 



The analysis of variance showed a significant dif- 

 ference in mean depths of the head length groups 

 (F = 35.9, F(table; a . 0.01) = 1.79). The Student- 

 Newman-Keuls test divided the group into two 



significantly different subsets; one 10-50 mm HL and 

 the other 51-70 mm HL. 



Other macrourids (N. bairdii and N. aequalis) had 

 high biomass but low numerical abundance at the 

 deep end of their ranges, indicating the presence of 

 a few large specimens there This was not the case 

 for C. c. carminatus (Fig. 5). The occurrence of fish 

 distributing by size can be obscured if the larger 

 members of the population traverse the entire range 

 The biomass of the species would be elevated at the 

 shallower depths so that a consistent biomass level 

 is present throughout the depth range Comparison 

 of Figure 4 with Figure 5 shows that although the 

 mean depth of capture for this species increased with 

 head length, the larger fish occurred over the en- 

 tire depth range This pattern is important because 

 it shows that for some fishes the "bigger-deeper" 

 phenomenon described by Polloni et al. (1979) may 

 really be a "smaller-shallower" phenomenon. A plot 

 of mean fish weight against depth as used by Polloni 



38 



