205 The flamingo quadrille 



begin in the cooler and less saline depths of the ocean holes. These 

 conditions result in a specialized group of birds that can exist 

 within such a restricted habitat. Again, these are limited as to 

 species but not as to quantity. There are stilts, egrets, herons, and 

 others that feed on killifishes and aquatic insects, but the prime 

 example is the flamingo, which may crowd into the Upper Lakes 

 at the start of the breeding season in vast multitudes that, even in 

 recent years, has approached 10,000 individuals, the largest assem- 

 blage of this species that now survives anywhere. These great flocks 

 quit the nesting lakes when the young are able to fend for them- 

 selves, leaving the remaining food supply to their growing off- 

 spring. Nor do they generally occupy the same breeding site two 

 years in a row. There are too many of them, and their demands 

 as to daily supplies of food are too great. The whole pattern seems 

 to be beautifully worked out, and although we are sometimes 

 prone to express bewilderment and impatience with what appears 

 to be the capriciousness of the flamingos, it is likely that they are 

 simply reacting to conditions and influences so carefully attuned, 

 so finely balanced, that we have difficulty in recognizing them 

 or in understanding what we see. 



Through the winter months the Inagua flamingo flocks have 

 been content to feed and rest in leisurely fashion in the coastal 

 ponds and lagoons, away from the big lake. They are more vulner- 

 able near the shore, for it is easy to reach most of these places by 

 boat from the sea, but the flocks are scattered and wary, and little 

 harm can come to them. They are not tied down to any one spot, 

 as is the case at nesting time. Then March arrives, pregnant with 

 change, bursting with the promise and the challenge of the vernal 

 equinox. Within the birds themselves progressive changes also 

 have been taking place. Restlessly they begin to move about more 

 and to show signs of involuntary reaction to an inward pressure. 

 What has been called "the hereditary clockwork of the popula- 

 tion" is now rhythmically ticking off the minutes of a new phase 

 in the cycle. To the histologist each stage in the physiology of this 

 cycle is measurable the changes can be interpreted by weights, 

 graphs, metric scales, and photomicrographs. To the ethologist, 

 who studies the psychological aspects, each stage is a series of 



