WHEN MAN MUST REDUCE NATURAL ENEMIES.

Forest and Bird, Issue 25, 1 October 1931, Page 15

WHEN MAN MUST REDUCE NATURAL ENEMIES.

Man must reduce (not exterminate) certain natural enemies of birds: (1) when he attempts to rear poultry or game birds in excessive numbers; (2) when, because of the disturbance of the biologic balance caused by extensive agricultural operations, he needs to increase the number of insectivorous birds beyond what the land naturally would support; (3) when the most sagacious natural enemies of birds, like the fox and the crow their own enemies having been reduced or exterminated by man himself advantage of the extra protection and food afforded them in civilised communities and, thus become too numerous and too destructive; (4) wherever man hunts and destroys wild game he may also reduce somewhat the number of the enemies of the game and thereby relieve the game of a part of the pressure brought to bear against its increase. In all such cases discrimination must be used, and it is unsafe to reduce too far the numbers of any but the most powerful predatory animals. —“ The Natural Enemies of Birds,” by Edward Howe Forbush.