arouses their sense of fear and suspicion, and they may keep away for a time or advance with caution. If very shy, like most catbirds, they will sometimes skirmish about the tent for two hours or more before touching the nest. The ice is usually broken, however, in from twenty minutes to an hour, and I have known a chipping sparrow and red eyed vireo to feed their young in three minutes after the tent was in place.
At every approach the birds see the same objects which work them
no ill. The tent stands silent and motionless, but the young are close by, and fear of the new objects gradually wears away. Parental instinct, or in this case maternal love, for the instinct to cherish the young is usually stronger in the mother, wins the day. The mother bird comes to the nest and feeds her clamoring brood. The spell is broken; she comes again. The male also approaches, and their visits are thereafter repeated.
Possibly the fears of the old bird? are renewed at sight of the
