THE NIDIOLOGIST. 



75 



STUDY IN NEST CONS f RUCTION. 



BY EPIG^A REPENS. 



There are very few species of birds whicli 

 habitually use the same nest for several 

 seasons, or even two seasons. In my ex- 

 perience, the Red-tailed and Red-shouldered 

 Hawks are more given to this habit than 

 any other birds in southern Michigan, and 

 these two, especially the former, are 

 known as species which hold to one eyrie 

 for many years, if undisturbed. Even 

 when robbed, the two Buteos will often lay 

 a second time, and a third time, in the same 

 nest in one season, in rare instances. The 

 Fish-hawk and Bald-headed Eagle are well- 

 known examples of attachment to a chosen 

 site, and it is a common thing, as I have 

 found from Florida to lyake Superior, to 

 hear eyries spoken of as having existed for 

 five to ten years, and even longer 



Nest building by the larger Hawks is 

 certainly quite an undertaking, and it is not 

 to be wondered at that it is desirable for a 

 pair of Buteos to simbly add a few twigs and 

 the lining each spring, in ' preference to 

 building a new nest. The fact that a pair 

 of birds have become attached to a locality 

 is often proven when the nest is robbed, by 

 their starting another nest in the same 

 neighborhood, in some instances but a few 

 rods from the old site. Once or twice, 

 where the second nest was robbed, the pair 

 again adopted the first nest. 



As a rule, with comparatively few ex- 

 ceptions, the Great-horned Owl, when not 

 selecting a hollow for its nest, chooses an 

 old Buteo's nest for its prospective brood, 

 merely making very scanty additions to the 

 nest lining. This Owl is very shiftless in 

 its attempts at nest construction at all times, 

 and seems contented with anything sub- 

 stantial as a foundation. 



The lyong-eared Owl, also, often selects 

 an old nesting site, generally preferring the 

 habitation of the common Crow. This is 

 fi.tted up in a manner to surprise the former 

 owners, if they happen to visit the spot. 

 An addition is built up, and the deep hol- 



low formed is comfortably lined with 

 feathers, which must be gathered at con- 

 siderable trouble. The appearance of this 

 nest is very pleasing, with the six eggs 

 artistically and thoroughly surrounded by 

 the thick, warm lining. One would never 

 imagine, from the rough and dilapidated 

 exterior of this old Crow's nest, that it 

 conld hold such elegance of style and 

 comfort. 



All of the Herons, so far as I can learn, 

 are gregarious in nesting season, to a 

 greater or lesser extent, and their old nests 

 in groups are often found; as an evidence 

 of former breeding sites. The Bittern's 

 nests are of course quickly obliterated, 

 from the nature of the material — grass and 

 rushes — and the low situations ch;sen; but 

 those of the tree Herons are more lasting. 

 The Green Heron's nest will be recognized 

 generally one, two, or even three years 

 after it was built. The bulky structure of 

 the Great Blue Heron is so substantially 

 and densely built that the nests are often 

 identified eight or ten years after the birds 

 have left, and I hnow an- old heronry where 

 the evidences were seen all of fifteen years 

 subsequent to the last breeding. The 

 nests are great straggling afiairs, and are 

 made of coarse and usually very long twigs. 

 Mixed in with the larger sticks are many 

 smaller twigs, arranged very artistically, if 

 we may consider the work as done by a 

 long-legged, ungainly bird. The nests, 

 when placed in a strong, live tree crotch, 

 are among the most durable that we can 

 find, and will outlast a Hawk's nest, which 

 at best is easily dismantled by a few 

 kicks. 



As a rule, the larger birds are content 

 with nests which are nearly flat on top, 

 while the further we go with the smaller 

 birds, we find that the nests are more hol- 

 lowed. As examples we will cite the nests 

 of the Bald Eagle and Red-tailed Hawk in 

 comparison with the extremely hollowed 

 nests of the Hummer and Gnatcatcher. 

 However, there is nothing yet discovered 

 to prove conclusively why these conditions 



