14 TH Et AV D UBIO SB Ul eee 
where the gamekeepers were most active in destroying what they considered 
vermin.” 
The quail of South Carolina are sometimes attacked by a contagious 
disease which makes the birds so stupid that they come out into the open 
and stand or lie in the sun. Hawks readily pick them up and the progress 
of the disease is stopped. Certain preserves are known to have been 
stripped of quail because of the trapping of the hawks which had kept down 
the disease. 
Similarly, the injured, deformed, and those whose reactions are slower 
are among the first to be captured and killed, while the strong and active 
individuals escape to continue the species. Albinos and others that do not 
have the protective coloration of their kind are more easily seen and are 
more readily caught, thus preserving in the succeeding generations the 
natural color patterns of the species. It is evident that the production of 
excess young is of service in maintaining a species only when natural 
enemies check that increase by removal of the unfit. 
But it is not all so simple as the above would make it seem. There.are 
other natural enemies of the birds than the hawks, owls and other birds. 
They include weasels, squirrels, snakes, rats, mice, etc., which, if they were 
permitted to increase without check, would bring about similar disastrous 
conditions. A single pair of meadow mice in a single year produced 83 
young. These young begin to breed when about 46 days old, and the total 
descendants of one pair, if all lived and bred, has been estimated at over a 
million mice at the end of one year. Meadow mice are not a great menace 
to birdlife, but this great excess of production furnishes a large source of 
food supply to the hawks and owls that might be more seriously destructive, 
and so the mice are of service to the birds if they themselves are held in 
check. Incidentally, the loss in the United States due to rats and mice in 
buildings and on the farms runs into many millions of dollars annually, and 
would increase enormously if they were not controlled by their natural 
enemies. All excessive killing of hawks and owls is therefore, if only for 
this reason alone, definitely against good public policy. 
Some strange combinations have been traced in this balance of species 
against species. The skunk is commonly known to seek out and destroy the 
nests and eggs of ground-nesting birds such as the grouse, pheasant and 
quail. On the other hand, the snapping turtle is a real menace to young 
waterfowl that frequent shallow waters to escape the danger from large 
fish. Dr. Edward Howe Forbush tells of watching turtles during four sum- 
mers while they deposited their eggs near the shore of a river. In every 
case, within 24 hours skunks had unearthed and eaten every egg. Thus the 
turtles, by providing a supply of eggs, quite likely attracted the skunks 
away from the birds’ eggs and saved many early broods. Again, on the 
other hand, the skunk, by destroying the crop of young turtles, befriended 
the young ducks, and a strange circle of unintentional protection was 
completed. 
The large hawks, too slow themselves to catch most small birds, feed 
commonly on snakes, frogs and squirrels, which are enemies of those same 
