DISTRIBUTION AND GENERAL NOTES ON THE SPECIES 



321 



Gunther noted its colour as 'slatey blue, darker above, a purer blue laterally, white ventrally'. Its 

 general distribution in our catches (markedly southern and in deep water) is shown below: 



IVS80 



WS99 



WS216 



WS217 



WS218 



WS816 



WS817A 



154 m. 

 238 m. 

 176 m. 

 146 m. 

 279 m. 

 150 m. 

 196 m. 



4 

 10 

 I 

 I 

 I 

 I 



58 



WS817B 



WS818A 



WS818B 



WS819A 



WS819B 



WS820 



WSS21 



220 m. 

 275 m. 

 281 m. 

 320 m. 



359 m- 

 464 m. 



52 



52 

 222 



27 



72 



22 



I 



IVSS25 

 WS839 

 WS840 

 WS850 

 WS868 

 IVS870 

 IVS875 



140 m. 

 418 m. 

 415 m. 

 161 m. 

 164 m. 

 272 m. 

 243 m. 



2 

 I 



5 

 12 



7 

 I 



5 



We have already had occasion to note that Micromesistius australis seems to inhabit higher latitudes 

 (for the most part) than its European relative. We never found Merluccius hubbsi to have been feeding 



upon it, although as a result of Hickling's work 



LENGTHS-CMS. it has long been known that Micromesistius pou- 



35 40 _ 45 50 ^^^(^ is one of the most important forage species 



for the larger European hake. The two European 

 species overlap almost throughout their lati- 

 tudinal range, while off Patagonia Micromesistius 

 occurs mainly to the south of the range of all 

 but a very few of the hake. 



It can be seen above that all our specimens 

 of M. australis— excepting one haul of 10 in 

 49° 42' S and three singletons farther north 

 in autumn and winter — were obtained in the 

 southern region south of 50° S. It is also very 

 clear that it is a deep-water species, very rarely 

 to be taken on the shelf in numbers. All but 

 one of our richer hauls were obtained in deep 

 water beyond the shelf edge. It was present in 

 all three of the deepest trawlings made, in depths 

 of over 400 m. 



A study of the length frequencies showed 

 some remarkable features. All were very strongly 

 unimodal and of very narrow dispersion. The 

 pooled frequencies for the January stations, 

 worked fairly close together in the southern 

 region, over a brief period, are shown in Fig. 32. 

 These data yielded mean lengths of 41-5 cm. 

 ((7=2-6257) for males and 43-2 cm. ((T= 3-2392) 

 for females. The difference of 17 cm. is clearly 

 significant. The slightly larger size of the females 

 (a well-known feature in many diverse species 

 of fish) might be expected to increase their 

 chances of capture with the result of a slight 

 'spurious' preponderance of females in the 

 catches The sex ratio observed however was strikingly ' abnormal ' in the unexpected direction-77 % 



the J':^^^^^ males. This suggests the Po-biUty of a tendency tow.^^^^^^^^ 



ir. this species during the non-breeding period. (The ponderal indices show a steady rise from January 



Fig. 32. Percentage length frequencies of Micromesistius 

 australis, January 1932. 



