412 THE BIRDS 



with a broken wing. The predator will probably give chase, thinking 

 that this will be an easily obtained meal. However, after leading him 

 quite some distance away from the nest, the quail will majestically rise 

 in the air, with the characteristic whirring of her wings, leaving the 

 puzzled predator behind, a safe distance from the nest. 



After the eggs have hatched, the mother, and sometimes the father 

 bird, spend most of their time searching for food to try to satisfy the 

 ravenous appetites of their offspring. They cram the food down the 

 throats of their babies, for most young birds are not able to swallow 

 properly. Many of the sea birds swallow fish and latter regurgitate the 

 partially digested fish to feed their young. Pigeons secrete a nourishing 

 liquid from their crop, which is called pigeon milk, that is used to feed 

 their squabs. 



Many game birds, including quail, pheasants, grouse, and chickens, 

 have offspring which have their eyes open and their bodies covered with 

 down feathers when they hatch. These are known as precocious young. 

 They are able to run about and pick up their food from the time they 

 are hatched, and their parents do not put food into their mouths. The 

 birds which are hatched as blind, naked, completely dependent offspring 

 are known as altricial young. For the first seven or eight days a nestling 

 robin, as an example, is nearly naked, and experiments show that its 

 temperature will drop quickly if not kept brooded by a parent. Thus, 

 it is actually cold-blooded like the reptilian ancestors. Young birds, 

 such as the hummingbird, exercise their wings on the edge of the nest 

 until they are able to fly successfully the first time they leave the nest. 

 Thrashers, mockingbirds, catbirds, and many others of our common 

 dooryard birds, usually jump from their nest two or three days before 

 they can fly. During this period of time they must hide in the weeds 

 and bushes where their piercing hunger calls lead their parents to them 

 with food. It is during this unprotected period that house cats and 

 other predators take a tremendous toll of young birds. After they can 

 fly, the fledglings will follow their parents from tree to tree for about 

 ten days or longer. With wings fluttering and mouths open widely, 

 they noisily beg for food. 



Soon, however, the mother birds starts to build another nest for her 

 second brood. She now appears to lose interest in her first brood and 

 not only stops feeding them, but often chases them from the neighbor- 

 hood. They now must fend for themselves. She has devoted her full 

 time to their care for a period of about six weeks and now must give 

 her time to a new nest and brood. 



