SAND DUNES AND SALT MARSHES 



life, for he prefers to feed by night, and when 

 the whistler goes to sleep on the sea, he arises 

 from his daytime slumbers in the same region 

 and repairs to the marshes. These two ducks 

 are the Box and Cox of the marshes. I have 

 seen great flocks of black ducks floating in 

 a long line off the beach in the bright sunlight, 

 most of them fast asleep. They are alert 

 birds, however, and cannot be caught nap- 

 ping, for there are always some on the watch, 

 and even the sleepiest awake from time to 

 time, stretch their wings and yawn, as they 

 look about before settling down for another 

 nap. Occasionally, and especially in stormy 

 weather, one may be fortunate enough to find 

 a great black mass of these birds sleeping on 

 the beach. They present a curious sight, and 

 loud is the roar of their wings as they rise 

 into the air. Unlike the sheldrake, the black 

 duck does not need a rim to launch his aero- 

 plane into the air, but has strength of wing 

 enough to rise straight up even in a dead calm. 

 Unlike the sheldrake, also, the black duck is 

 present in the summer as well as the winter, 

 for it breeds in near-by swamps, and visits the 

 salt marshes for food. There are reasons for 

 believing that our summer black duck is a 



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