BROOD-CARE IN BIRDS 161 



have seen cygnets taking refuge on the back of the male or female 

 swan, nestling under their wings as they swim (see Plate XI, p. 240). 



When the young are helpless, the parental care and protection 

 are even greater. Birds which are naturally timid will fly out and 

 strike savagely at disturbers of their nests and young, whilst those 

 that are strong and predatory are extremely dangerous to approach, 

 when they are with eggs and young. Most of them take great trouble 

 with the sanitation of the nest or of the breeding-hole, first them- 

 selves carrying away the droppings of the young birds, and after- 

 wards encouraging the nestlings to void their excretions over the 

 edge of the nest. There are a few birds, such as hoopoos and 

 kingfishers, which take no trouble in these matters, but the nests and 

 the bodies of most young birds are kept scrupulously clean. 



Finally, in all cases where the young are helpless, and in a good 

 many where they are active, one or both parents work assiduously 

 in feeding them. Whatever be the natural diet of the adults, the 

 food of the young is almost always animal matter. There are of 

 course some exceptions. Ostriches, almost as soon as they are 

 hatched, begin to crop green herbage for themselves, although 

 cassowaries, emus and rheas require food such as insects and spiders. 

 The secret of rearing ducklings of almost every kind is to supply 

 them abundantly with the common duckweed of ponds, and although 

 there is usually a rich microscopic animal life adherent to these 

 plants, the bulk of the food is vegetable. But all the soft-billed 

 birds, which are naturally insectivorous, most of the fruit-eaters 

 and practically all the hard-billed seed-eaters work from dawn to 

 dark searching for grubs, caterpillars, maggots, worms and all 

 manner of creeping and flying things. to feed their hungry young. 

 Other birds hawk insects on the wing for the same purpose, and those 

 who resent the occasional devastations of their fruit-gardens and 

 seed-beds should remember that human life would be almost in- 

 tolerable, and the toil of the gardener and farmer almost futile, 

 were it not for the destruction of insects and their larvae which is 

 the work of birds engaged in feeding their young. 



Many birds feed their young on food which they have partly 

 digested and throw up. Some of the finches, which at first bring 

 insects to their young, afterwards feed them on partly digested 

 food. Parrots also digest their vegetable food and supply it to the 

 young in this condition, whilst some woodpeckers, martins and 

 others throw up digested insects. Storks break up frogs, worms, 

 pieces of fish or flesh, mix it with partly digested matter and throw it 



C.A. L 



