AVES 197 



and vegetable food is scarce our winter residents fairly comb the trees 

 for these wintering larvae, which must be carefully hidden to escape the 

 sharp eyes of the hungry birds. 



It is obvious then that every means should be employed to protect 

 and encourage our native birds, and some of the ways in which this 

 may be done will be briefly described. Two main lines may be followed 

 in bird preservation; (i) control of bird enemies and (2) direct protec- 

 tion and encouragement of the birds themselves. 



According to Forbush the numbers of birds in Pennsylvania de- 

 creased over 50 per cent, in 15 years; this decrease was due largely, 

 though not entirely, to their destruction by their enemies, chief of 

 whom is man. Man, the worst enemy of all living things, has killed 

 birds by the m'llion, for food, for plumage and for mere wanton sport. 

 Man also includes the small boy, and the boy that is not so small, 

 who not only kills birds with guns and other weapons but who also 

 robs the nests, in the collection of bird eggs, a habit that should be 

 discouraged in every possible way. Perhaps the worst offenders 

 against the bird life of the country are the foreign laborers, who 

 slaughter indiscriminately every bird, large and small, that comes 

 within range. Vigorous laws against hunting on Sundays have helped 

 diminish this nuisance, and other game laws, to be discussed later, 

 have done much to save many species from extinction. Man has 

 also done much, unintentionally, to diminish the bird population by 

 clearing woodlands and thickets, draining swamps, etc. 



Of the so-called natural enemies of birds the house cat is probably 

 the most destructive, especially the half-wild kind that is seen about 

 every farm, village and city. It is estimated that cats kill, on an 

 average, from 10 to 50 birds each year; if only 10 per year are killed 

 the total for the State of Massachusetts would probably be about 

 700,000. Another estimate gives the total birds killed by cats at 

 31,000,000 per year. Whatever the number may be it is probable 

 that cats destroy more birds than all the other animals (excluding man) 

 combined. Although of value as destroyers of rats and mice, in some 

 cases, as will be noted later, it is probable that the country would be 

 better off if the race of domestic cats were exterminated. Many a 

 farmer that will kill a cat for catching a very occasional small chicken 

 seems to pay no heed whatever to the continual destruction of birds, by 

 the dozen or more cats about the place. 



