Birds' Nests and Eggs 



The ways of birds are diificult to understand. Why should 

 some build in colonies, and others singly but in close proximity, 

 and others again miles away from their kind ? The passenger 

 pigeon gives the best example of nest colonies, immense numbers 

 breeding in a very limited area. Prof. H. B. Rooney speaks of 

 a nesting area forty miles long and from three to ten miles wide, 

 where, in 1878, a million and a half of the pigeons were killed for 

 food purposes, while if those that were taken alive and the dead 

 nestlings were included, the number would reach the enormous 

 total of a thousand millions. This is thought to be somewhat ex- 

 aggerated, but shows what an immense number of birds must 

 have been breeding in this limited space. Some of our smaU birds 

 nest in colonies ; among them the red-winged blackbird and some 

 of the swallows afford the most noticeable examples. The bobo- 

 link and marsh wrens also live in scattered communities during 

 the breeding season. Most of the larger hawks select a desirable 

 copse or fairly large tract of woodland as a common home, and it 

 is seldom that another nest of the same species is found within 

 that area. In Florida, where each cypress swamp is usually clearly 

 defined, it is seldom, except in the large swamps, that one finds 

 in each more than one nest of the Florida red-shouldered hawk — 

 a species very abundant throughout the more southern parts of 

 the State. 



Some birds return regularly year after year to the same nest- 

 ing site, even after their nests have been robbed several times. I 

 have known a crested flycatcher to build in the same hole for 

 three years in succession though each set of eggs was taken. 

 Phoebes return with great regularity to the same bridge, building, 

 or rock, where they make one or two nests each season. Some 

 of the owls also use the same hole for many years, and hawks 

 and crows rebuild their old nests, so that each year the nest be- 

 comes larger as layer after layer is added. 



Most, if not all, birds are governed in their habits by regular 

 rules — from which, however, they occasionally depart just as 

 human beings depart from the rules which seem most generally 

 applicable. 



The Wilson's thrush, whose nest is commonly on or near the 

 ground, has been known to build in a hole in a tree. Bob-whites' 

 nests containing thirty-seven eggs have been reported — though 

 these were, of course, not all laid by one hen. The eggs were 



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