REED WARBLER 



It is remarkable that many, deep as the nest is now, are not 

 precipitated headlong into the water; but their long legs and 

 their innate power of clinging, no doubt make their position 

 more secure than it often really appears to be. The nest is 

 one of those beautiful adaptations of Nature which justly excite 

 our wonder and admiration, for on the one hand it must be 

 sufficiently deep to eliminate all possible risk of the young 

 being thrown out, while on the other it must not be too deep 

 to retard the process of incubation. If the depth were too 

 great, there would be a danger of the young in their early 

 stages of growth not being sufficiently covered with the feathers 

 of the parent bird to ensure their bodies being maintained at 

 a proper temperature. How important this must be in the 

 case of the eggs can be readily understood, but it is even more 

 important — and this can be inferred from the behaviour of the 

 parents — to maintain the young for the first few days after 

 they are hatched at a certain temperature. Sleep is to some 

 extent dependent upon warmth, and sleep is a vital necessity 

 for the helpless naked young; therefore if the nest were too 

 deep they would not be properly surrounded with the breast 

 and belly feathers of the parent birds. Even as it is, the 

 female when brooding appears to me to be in a most uncom- 

 fortable position. In the construction of the nest she does 

 the greater part of the work, carrying billsful of the seed-heads 

 of the reeds, which she rapidly fixes, and as soon as the outer 

 part of the nest is completed and it begins to take its proper 

 form, she lies in it and shapes the interior with her breast by 

 turning this way and that, and at the same time often uses her 

 bill to assist in arranging the material in the interior. Her 

 efforts to build the nest are not without what appears to be 

 the usual hindrance caused by the exuberant spirits of her 

 mate, for, while she is at work, he often flies at and pursues 

 her, with the result that there is much fluttering amongst or 

 above the tops of the reeds, with an audible clicking of bills 

 as they meet. Five or six days may elapse between the time 

 when the nest is commenced and the laying of the first egg, 



45 



