BIRDS OF NEW YORK STATE 127 



Hummingbird Nu HuR3 



Wood pewee Nu Pi2 



Wood thrush Nu TiWS 



Redstart Nu Rfl 



d The inexperienced builder 



The instinct to build the type of nest characteristic of the 



species is inherited, but birds learn through experience to build 



stronger and better protected nests. The first nests built by 



immature birds are often quite poorly constructed and placed. 



Red-winged blackbird Nu B13 



e Duplicate nests 



Long-billed marsh wren, nest in use Nu WrL4 



Long-billed marsh wren, duplicate nest Nu WrL2 



In the wren family, the males are assiduous nest builders and 

 often build several nests before the arrival of the females and 

 continue thereafter building duplicate nests, which are not used 

 for anything unless it be for roosting. These duphcate nests 

 are usually much more conspicuous than the one in which the 

 eggs are laid. Note the conspicuousness of this duplicate nest. 



/ Nest repairing 



Red-eyed vireo Nu ViR 



g Relation of haunt of bird to nest material 



The materials which birds use in nest building are determined 

 largely by the haunt of the bird. The materials that are most 

 available are always used provided they are suited to the general 

 type of nest characteristic of the species. Birds that live in the 

 fields ordinarily use grasses and horsehair. Those that live in 

 the woods use rootlets and dead leaves, etc. Birds that spend 

 most of their time on the wing and meet with no particular set 

 of materials vary the most in their nest construction. 



Field sparrow, grass nest of field bird Nu SpF3 



Blackburnian warbler, rootlet nest of wood- 

 land bird Nu WA3 



Florida gallinule, reed nest of marsh bird Nu GcF 



5 Types of nests — evolution 



One of the most interesting phases of nest building is its evo- 

 lution from the most simple to the most complex form and con- 

 struction. One can trace in the nests built by birds today what 

 has been the probable evolution of the most complicated nests 



