10 



10 



lo- 



ws 73 



10- 



10- 



10- 



10- 



10- 



10- 



10- 



20- 



10 



WSS3 



WS97 



30- 



20- 



10- 



WS2I7 



W5859B 



Fig. 39. Percentage length 

 frequencies of TV. ramsayi at 

 autumn stations with more 

 than eighty individuals, show- 

 ing probable year classes. 



DISTRIBUTION AND GENERAL NOTES ON THE SPECIES 335 



and an arbitrary weighting system (based on some contemporary volumetric 



records) which provides some approximation to relative values of major food 

 categories, are shown in Table 34. 



Clearly N. ramsayi is much more of a bottom-feeder than most of the other 

 Patagonian species for which we have any data. Benthic Crustacea were the 

 largest item in the dietary observed, and a considerable proportion of poly- 

 chaetes were eaten. A'^. ramsayi, however, feeds heavily upon Falkland herring 

 whenever opportunity offers, though the same might be said of almost every 

 animal in the area capable of swallowing them, including such other typical 

 bottom-feeders as Cottoperca and some of the rays. In winter some plank- 

 tonic food was taken by some of the larger A^. ramsayi far offshore, and this 

 brings us to a point that the existing data are not adequate to solve, namely, 

 that it is highly probable that in this species, as in so many other larger 

 demersal fishes (cf. hake, cod, Macruroniis, etc.), increased size and mobility 

 is accompanied by a change-over from a carcinophagous to a fish diet. It is 

 therefore probable that our approximate diagram really represents a sort of 

 summation effect of the dietary of Notoihenia ramsayi over the whole of its 

 life, and that had it been possible to examine stomach contents of samples 

 of small fish and larger fish separately, we should find the organisms occupy- 

 ing (roughly) the upper and lower halves of the diagram in very different 

 proportions. I should expect the benthic invertebrates to be relatively more 

 important in the smaller Notothenia, and fishes to predominate in the larger. 

 Another notable feature is that no Miiiiida were recorded from the stomachs 

 of Notothenia ramsayi, but it is highly probable that they would have been 

 had it been possible to make summer observations on this point. 



Enough has been said to show that, if only on account of its small size, 

 A'^. ramsayi is not likely to be of much value as human food in spite of its 

 abundance within our area. The largest individuals of 35 cm. and upwards 

 may attain a weight of a pound, and are not less palatable than the (rather 

 insipid) larger Antarctic members of the genus. The average weight is little 

 more than J lb. however, and the majority of the trawled fish are just too 

 large to be fried and eaten as ' sprats ', a process that the crew of the ' William 

 Scoresby' found most efficacious with the young fry some 10-12 cm. long. 

 These were said to be '. . .exceedingly good, though the bones are rather 

 hard. The flesh resembles that of whiting'. 



A^. ramsayi is of the first importance as a forage fish for larger and more 

 useful species on the Patagonian Continental Shelf, being one of the main 

 sources of food supply for hake and Macruronus, as we have already seen. 



Notothenia wiltoni Regan. This species seems to be one of the more extremely 



littoral Nototheniiformes, though it may depart from the shallowest waters 



in winter. In our collections with ' Other gear' it was taken between 2 and 



35 m. of water at the Falkland Islands and in the Magellan region, the mean 



depth being but 5 m.: 



Port Stanley 45 (by A. G. B.) 56 2 (in BTS) 



Field Anchorage i (on LH) 222 i (m TNL) 



55 I (in BTS) 



None was taken at the regular trawling stations. 



15 



