very destructive in certain parts of the United States- — was found near a nest 

 of this species. 'I'he notalale increase of noxious rodents (hiring the last few 

 years in certain jKirts of the United States and the consequent damage to crops 

 are due in no small part to the diminished numher of loirds of prey, which 

 formerly destroyed them and aided in keeping flown their mmihers. A few 

 hawks are injurious, and the hulk of the depredations on birds and chickens 

 chargeable against haws is committed by three species — the Cooper's hawk, the 

 sharp-shinned hawk and the goshawk. The farmer's boy should learn to know 

 these daring robbers by sight, so as to kill them whenever possible. 



From the foregoing it will at once appear that the practice of ottering 

 bounties indiscriminately for the heads of hawks and owls, as has been done 

 b\- some states, is a serious mistake, the result being not only a waste of public 

 funds but the destrtiction of valuable birds which can be replaced, if at all, only 

 after the lapse of years. 



As a rule birds do not live very long, but they live fast. They breathe rapidly 

 and have a higher temperature and a more rapid circulation than other verte- 

 brates. This is a fortunate circumstance, since to generate the requisite force to 

 sustain their active bodies a large quantity of food is necessary, and as a matter 

 of fact birds have to devote most of their waking hours to obtaining insects, 

 seeds, berries and other kinds of food. The activity of birds in the pursuit of 

 insects is still further stimulated by the fact that the young of most species, even 

 those which are by no means strictly insectivorous, require great quantities of 

 animal food in the early weeks of existence, so that during the summer months— 

 the flood time of insect life — birds are compelled to redouble their attacks on our 

 insect foes to satisfy the wants of their clamorous young. 



Field observations of the food habits of birds serve a useful purpose, Init they 

 ,ire rarely accurate enough to be fully reliable. The presence of certain birds in 

 a corn or wheat field or in an orchard is by no means proof, as is too often assumed, 

 that they are devastating the grain or fruit. They may have been attracted by 

 insects which, iniknown to the farmer or orchardist, are fast ruining his crop. 

 Hence it has been found necessary to examine the stomachs and crops of birds 

 to ascertain detinitely what and how much they eat. The Biological Survey has 

 in this way examined upward of 50,000 birds, most of which have been obtained 

 during the last 25 years from scientific collectors, for our birds are too useful to 

 be sacrificed when it can possibly be avoided, even for the '^ake of obtaining data 

 upon which to base legislation for their protection. 



Tt is interesting to observe that hungry birds — and birds are hungry most of 

 the time — are not content to fill their stomachs with insects or seeds, but after the 

 .stomach is stutifed until it will hold no more continue to cat till the crop or gullet 

 also is crammed. It is often the case that when the stomach is opened and tiie 

 contents piled up the pile is two or three times as large as the .stomach was 

 when filled. Birds may truly be said to have healthy appetites. To show the 

 astonishing capacity of birds' stomachs and to reveal the extent to which man is 

 indebted to birds for the destruction of noxious insects, the following facts are 



