$4' THE CONDOR ol. XV tural dangers, and its remarkably slow rate of increase was doubtless great enough to easily maintain its numbers under the conditions obtaining be[ore the appearance of the white man and his firearms. FACTORS FAVORING TI-IE PERSISTENCE OF THE PIGEON As we reflect upon the above facts of slow increase and gregarious habits our only'marvel is that the pigeon has been able to maintain its existence at all in face of the fifty years or more of hunting to which it has been subjected without restraint. The factors which have allowed the persistence of the bird against this new and adverse condition are probably included among the following. (I) The birds repair to forested areas for the breeding season. These are mostly in rough, mountainous country, sparsely settled by man. It is likely, fur- ther, that owing to the forest reserve system, of more and more recognized value as a governmental institution, these summer retreats will never be wholly de- stroyed through clearing or settlement. (2) The pigeon does not nest in colonies, but the individual pairs scatter out through the woods. (3) The pigeon is secretive in its nesting habits, so that the nests are not subject to molestation by marauding humans or beasts. "Their nests are mere platforms and hard to see; owing to the surrounding foliage, they are not readily discovered except by the actual flushing of the bird. One must be quick even to see the bird. It does not flutter along the ground in the manner of the Mourn- ing Dove, nor does it sit on a nearby branch and .coo, but is off like a shot; and it requires a pretty sharp eye to follow its flight through the trees" (Sharp, I9O2, p. I6). (4) In winter, although iche pigeons gather in large flocks and concentrate in limited districts, they are irregularly distributed from year to year. That is, al- though they may be hunted to the verge of annihilation in a restricted area one season, the residue is not likely to return to the same locality the following year, and so be subjected to a repetition of?the catastrophe. The nature of the food and the fact that this is of variable supply, leads to the wintering of pigeons in re- curring seasons in rough niountain country where they. are largely out of reach of hunters, thus giving the birds frequent respite. (5) Several writers and observers, even as far back as Cooper (I87O, p. 5o7), comment upon the quickness with which the pigeons become wary when shot at. They learn suspicion of hunters; "their shyness is probably due to the fact that in their passage from the north they are compelled to run the gauntlet of hundreds of gunners" (Henshaw, I876, p. 265). And here is one benefit which accrues from the flocking habit: individual safety is attained through community watchfulness. This m&y be considered as in part counter-balancing the possibility of pot-shooting numbers of the birds at one time because of their being massed in a flock. The gregarious habit brings to the hunted bird both benefit and danger; but with the increased deadliness of firearms, the constantly augmented numbers of hunters, and the ever greater fa- cilities for quickly reaching a locality where pigeons are known to have appeared, it would seem that the flocking habit brings disproportionatel? greater danger to the birds, as time goes on. TI-IE DESTRUCTION IN I912 Judging from recorded accounts, it is only at ra, re intervals that such a
