IS4 DISCOVERY REPORTS 



In our own waters M*^Intosh (1887) reports a mass stranding of Meganyctiphanes norvegica on what 

 seems to have been an equally grand scale, an occasion when this species was washed up in such 

 multitudes on the east coast of Scotland that miles of sand in St Andrews Bay 'were strewed with their 

 bodies which receding wavelets left in streaks and curves ', Mcintosh adding in a footnote that when 

 dried 'they closely resembled chaff, for which, indeed, the uninitiated took them'. On another 

 occasion (Robertson, 1892) the surface waters of Upper Loch Fyne appear to have become so choked 

 with M. norvegica that the Duke of Argyll had over 24 lb. cooked and served for breakfast ! 



Fisher, Kon and Thompson (1953), referring briefly to the swarming of M. norvegica in the 

 Mediterranean, cite Lo Bianco (1902, 1903) who reports daylight concentrations on the surface at 

 Capri so dense that fishermen, casting for bait, were taking it sometimes by the hundredweight. 

 In the same paper Kon records its spectacular swarming in the port of Monaco, reporting an occasion 

 in February 1952 when it was thrown up on the beach in such astronomical numbers that municipal 

 carts had to be employed to remove the bodies. 



The intense surface crowding of the Antarctic krill and of other euphausians in both southern and 

 northern hemispheres is paralleled among the aggregate forms of certain Salps, Sars (1829) recording 

 an historic occasion when these animals, evidently Salpa fusiformis, appeared in such fantastic 

 numbers on the surface off Bergen that in certain places where they were thickest boats had difficulty 

 in putting out to sea. Yet another parallel is presented by shoaling fish. There was an occasion in 

 January 191 3 when the Pacific herring {Clupea pallasii) crowded into an Alaska bay in such enormous 

 numbers that hundreds of thousands, perhaps millions, became stranded, their bodies left piled in a 

 solid mass, in places several feet deep, when the tide went out (Brongersma-Sanders, 1957). Similar 

 catastrophes, involving the stranding of ' thousands of tons ' of dead fish, are well known on the coast 

 of south-west Africa near Walvis Bay (Brongersma-Sanders, 1948; Copenhagen, 1953; Hart and 

 Currie, i960). 



So far then as can be seen from the decks of vessels in daylight the krill are manifestly concentrated 

 in dense patches on or very close to the surface of the sea, and although in the rather turbid water of the 

 Antarctic nothing as a rule can be seen beyond a few metres down, it will be shown later (pp. 157-70) 

 that it is largely to the surface zone, or to not very far below it, that the main concentrations of the 

 whale food are in fact confined. 



Habits and behaviour 

 In view of the relatively large size to which it grows, its vivid colouring, shoaling habit and pre- 

 dominantly surface habitat, the behaviour and movements of E. superba can be studied at closer range 

 and observed perhaps with greater accuracy than those of most other organisms of the plankton. 

 Continuing his description of the krill swarm from which I have already quoted, Hardy goes on to 

 say, 



They were all swimming hard and going round and round, sometimes in a circular course, and sometimes in a 

 'figure 8', but never breaking away from the one mass. The cloud would sometimes change shape, elongate this way 

 or that (There appeared to be some guiding ' principle ' — almost as if there was some leader in command of the whole !). 

 At times they would form into two such moving parties and one would tend to separate from the other, so that the 

 swarm became dumb-bell shaped ; but as soon as the connecting link became of a certain thinness the one part would 

 turn back and flow into the other to form one big swarm again. It was drawn into the whole like the pseudopodium 

 of an amoeba ; indeed the whole swarm appeared to behave as one large organism. It was for the most part at the 

 surface, but at times the whole would sink down almost out of sight to rise again. This would happen apparently 

 spontaneously, or again happen if some sudden disturbance occurred, the approach of a boat for instance. They were 

 so close to the pier, at times even below it, that one could look straight down on to them and observe them with ease. 

 I put in my walking stick and stirred the whole swarm up quickly so as to scatter them in all directions; but within 

 half a minute they were all back again in their old formation. 



