SWARMING 47i 



(27. iv. 27, St Francis' Bay, Cape Horn) 95 adults of both species were taken on the 

 bottom at 63 m. in a haul of only 7 min. duration. Similarly at St. WS 576 (17. iv. 31, 

 Berkeley Sound, East Falkland Islands) numbers of adults of both species were taken 

 on the bottom at a depth of 34-24 m. Thomson (1898, p. 194) has recorded of the adult 

 M. subrugosa that in New Zealand " occasionally it comes up Otago Harbour in countless 

 swarms, creeping up to the steps of the jetties and on to the submerged stones of the 

 piers. It always appears to keep near the bottom and is rather slow and sluggish in its 

 movements till pursued, when it jerks itself rapidly backwards". 



There are many records of swarms of the Grimothea stage of M. gregaria being seen 

 at the surface in South American seas. Some of the earlier records are quoted below 

 (p. 479). From New Zealand waters Young (1925, p. 318) records, " Munida gregaria 

 in its swimming stage visits Otago Harbour in large numbers during the warmer months 

 of the year. The shoals are so large that the water appears to be quite red with the 

 thousands of individuals which are clustered together. The smaller shoals often take a 

 circular shape like a swarm of bees, and the incessant motion of each individual tends 

 to heighten this illusion ". The occurrence of swarms in other parts of the New Zealand 

 seas is noted below (pp. 481-482) in discussing the relations of other animals to these 

 Crustacea. On the other hand, that the swarms of the Grimothea stage are not always 

 found at the surface is shown by the specimens in the Discovery collections from 105- 

 115 m. (St. 51) and 61 m. (St. WS 100). It is of interest to note in this connection that 

 Cheever (1850, p. 48), 1 speaking of the food of the Southern Right Whale, states, "the 

 living of this vast animal is thought to be upon a substance which I hear universally 

 called by whalemen ' right whale feed '. It appears in the water as a red-coloured insect. 

 ... It is, in fact, a little red shrimp, sometimes seen floating on the surface of these seas 

 alive, oftener dead, when it has the appearance at a distance of patches or clots of blood, 

 only yellower.. . .This 'feed' is supposed to lie generally rather deep under water in 

 these southern seas, as whales are often taken in greatest numbers where none of it is 

 to be seen on the surface". 



Information and specimens kindly supplied by Captain S. Fagerli of the S.S. ' Ernesto 

 Tornquist ' show that the adult M. gregaria also swarms at the surface of the sea at times 

 on the Patagonian coast. Captain Fagerli was whaling off the coast of Patagonia in the 

 seasons 1927-8 and 1928-9, and states that enormous shoals of adult M. gregaria were 

 observed at the surface of the sea all the way down the Patagonian coast from Bustamente 

 Bay in the Gulf of St George to south of Santa Cruz (latitude 45 to 50 S). After high 

 water with the wind on shore great numbers were seen washed up on the beaches. 

 Shoals of the Grimothea stage were also seen ; the swarms of adults and of the Grimothea 

 stage were observed from the shore out as far as 70 fathoms of water. Captain Fagerli 

 has presented to the Discovery collections specimens from Bustamente Bay, caught at 

 the surface in a small net alongside his ship as she lay at anchor. All the specimens, 101 

 in number, are adult M. gregaria, and were taken between March 23 and April 6, 1929. 



1 Cheever, Rev. H. T., The Whaleman's Adventures in the Southern Ocean. Ed. by the Rev. W. Scoresby. 

 London, 1850. 



