DISCOVERY 



47 



is described as " a growl with a bubble in it," and a 

 " rolling groan " ; perhaps I may leave it at that ! 

 In this position they swam rapidlv across the pool, the 

 male leading, uttering the or}' again and again ; they 

 then turned, and repeated the process, but with the 

 female now leading ; then stopped, and resumed the 

 ordinan,' business of life. We may call this form of 

 courtship the "beak-dipping ceremony." 



This was the commonest ceremonial of the birds. 

 I saw it both on the little lochs and on the big lagoon, 

 and the strange guttural cry that was its sure accom- 

 paniment came often to our ears, at all hours of day 

 and night. 



As far as ceremonies later than the time of pairing 

 up are concerned, the Diver is very similar to the 

 Crested Grebe, but with much less variety of courtship 

 action. The main point of resemblance is that both 

 male and female birds play either interchangeable or 

 identical roles ; there is no courting of one sex by the 



creatures' antics quite unintelligible. Among a group 

 on the lagoon, there would suddenly be a commotion ; 

 birds would be seen — usually a trio, but sometimes 

 two and sometimes four — ploughing the water in an 

 extraordinary- attitude. Their bodies would be sub- 

 merged (this power of voluntary submersion of the 

 body being common to all Grebes and Divers), but 

 tilted up in such a way that just the breast and 

 shoulders were above water. The neck was stretched 

 stiffly up and forwards, about 30° in front of the 

 vertical ; and the head inclined slightly downwards. 

 In this attitude they had a very remarkable appear- 

 ance, like miniature Plesiosauri restored to life. Again, 

 as often in birds' ceremonials, there was a tense, rigid 

 look about their attitude. Resistance to movement 

 must have been considerable, as a wave was thrown off 

 from their advancing breasts. In this attitude they 

 would progress for a considerable distance, less as if 

 one of them were being pursued than as if all were 



(l) THE BE.\K-DIPPIXG CEREMOXY. (;1 THE PI,ESrOS.\UR R.\CE. 

 EMERGEN'CE FROM DIVIXG. 



(3/ and (4) VERTICAL 



other exclusively, as in peafowl or black game or 

 warblers. 



I was particularly lucky, however, in seeing a good 

 deal of the earlier stages of courtship, those which lead 

 to the selection of mates for the season. These are 

 notoriously difficult to observe in most birds ; here 

 it was largely our good fortune in being close to the 

 lagoon which helped me to this result. The lagoon 

 served as a common rendezvous for all the Divers in 

 the neighbourhood. Sometimes they would fly out to 

 sea to fish, or across to the other side of the island ; 

 but a great deal of their fishing, and, above all, of their 

 resting and their courting, was done on the lagoon's 

 tranquil waters. I have seen as many as ten scattered 

 birds on it at once, and little flocks, real social gather- 

 ings of five or six, were not uncommon. 



During our first four days, the lochs were all frozen 

 over, and nesting was impossible ; it was then that 

 the selection of mates was going on most rapidlv. As 

 is usual with bird-watching, we at first found the 



running some form of race. (In fact we christened 

 the ceremony " the race of the Plesiosauii.") Then 

 they might turn about, and come back with a different 

 member leading. 



At other times they would give the same performance 

 but raised to greater heights of excitement, the wings 

 spread and drooped and beating the surface of the 

 water. 



Then we repeatedly saw the extraordinary spectacle 

 of one bird diving to emerge close to another in a 

 nearh' vertical position. The whole white under- 

 surface would be exposed to view, the bird seeming 

 almost to stand on its tail in the water, and then slowly 

 settling down to a sitting position. This vertical 

 emergence, too, is paralleled in the behaviour of the 

 Crested Grebe. 



\Mien it is remembered that the performance charac- 

 terising mated pairs was also to be seen on the lagoon, 

 that " splash-diving " was frequent, that fighting and 

 jealousy often gave rise to much confused action, and 



