PHYSICAL ENVIRONMENT 73 



The Weddell Sea, or at any rate such parts of it as are permanently covered, if conditions there are 

 as Nansen describes, may also perhaps be conceived as a vast storehouse of nutrient salts. It may be 

 remarked too that The Friendly Arctic of Stephansson (1921) refers essentially to the fringes of the 

 polar sea, where life is indeed rich,i and that while he is strongly disinclined to believe the existence 

 of Nansen's desert he produces no evidence (Stephansson, 1928) to suggest it could be otherwise. 

 Dunbar (1955 a), following Stephansson, also questions the reality of Nansen's desert, noting that the 

 results of the Papanin expedition of 1937, working deep in the Arctic pack, did not agree with Nansen's 

 conclusions. This expedition, however, hauling its nets through holes in the ice from depths as great 

 as 3000 m., must have been sampling in the main a bathypelagic population,^ the vertical horizon 

 examined not being confined as Nansen's was to an impoverished euphotic zone. Even so, as Dunbar 

 himself observes, the quantity of zooplankton encountered was 'not great', not 'in any remarkable 

 bulk ' when compared with the wealth of life encountered on the fringes of the polar basin. He adds 

 moreover, 'Whatever the production of life under the more or less permanent ice cover of the Arctic 

 Sea, it is certainly less than in arctic water that is free of ice during the summer, and the latter 

 production is, in turn, less than the production of life in the subarctic waters '. 



During the recent voyage of the U.S. nuclear submarine 'Skate' below the Arctic pack plankton 

 populations were found to be 'extremely sparse' and 'no acoustic scattering layers, as commonly 

 observed in other oceans and attributed to marine organisms, were found on the echo sounder trace ' 

 (LaFond, i960). 



Bogorov (1938) calls attention to the work of Shirshov at the Russian drifting ice station 'North 

 Pole', noting that Nansen's desert has now been found to be 'characteristic for the "winter" state 

 only, whereas during the biological "spring", as noted by Shirshov, there develops a tremendous 

 amount of planktonic algae and of diverse animals '. It is possible, however, that a more or less 

 permanent winter state exists in the impenetrable core of the Weddell Sea. 



Fraser (1936) suggests that as a result of the reduction of their food supply through the cutting off of 

 the sun's rays by ice, there will be a movement of the krill northwards to areas of richer grazing at the 

 periphery of the ice-field. 



That this happens [he says], is proved by observations on the circumpolar cruise [of April to November 1932] and 

 the voyage which the 'William Scoresby' made into the Weddell Sea [in January and February 1931]. The latter 

 instance is most striking because the ship penetrated far into an area which is normally ice-covered for the greater 

 part of the year, and the stations where krill was taken are all concentrated on the northern part of the line between 

 South Georgia and the point east of the South Sandwich Group where the ship turned southwards into the 

 water of the eastern Weddell Sea. No krill were taken in the part of the Weddell Sea which is normally ice- 

 covered, although the observations included a station at the ice-edge with hauls throughout a twentj^-four hour 

 period (St. WS 552). It cannot be doubted that krill does not penetrate far beyond the edge of the ice-field, and that 

 to some extent at any rate the concentrations met with in the vicinity of the pack are caused by the movement, 

 towards the periphery of the pack, of krill which was more uniformly distributed before the formation of the ice-field. 



This passage was written long before the publication of Mackintosh and Herdman's monthly 

 ice-charts, and its author was therefore unaware that the eastern part of the Weddell Sea, far from 

 being normally ice-covered, is open annually, as these charts show, from January right through to 

 May, and accordingly should more properly be described as a region subject to periodic covering by 

 non-permanent or temporary ice. As the route of the vessel lay across the Weddell drift from north to 

 south, across a region (Fig. 5 b) now known to be rich in whale food, I was surprised, in spite of 



^ Paulsen (1906), for instance, calling attention to the wealth of plankton north of Iceland, describes the water as 'literally 

 living with herring'. 



^ Dunbar notes that the variety of plankton animals captured included typical Atlantic forms and that these moreover were 

 taken in 'the Atlantic layer of water beneath the upper arctic water'. 



