10 THE AUD WBO N@B Ud bei 
What Warblers Do for Us 
, | \HE short period of time during the bird migration in which the 

Warblers may be seen is no doubt one of the reasons why so little 
is known of their great value as destroyers of insects. The thirty 
or more varieties of Warblers that are summer residents and migrants in 
Illinois do a service for the welfare of plant life that is beyond one’s 
ability to estimate. Their small size, activity, and habit of wandering 

Drawn by Carl F. Groneman 
YeELLow WarBLER, Active DesTROYER OF APHIDS 
from bush to tree with great rapidity accounts for the fact that so little 
is known by the average bird lover of their food habits. During the 
height of the Warbler migration the aphis or plant lice,which have already 
made their appearance and the different members of this family, form the 
principal food of the smaller Warblers. The native hawthorns are par- 
ticularly infested by aphids as are also roses, both cultivated and wild, 
the members of the viburnum family, golden glow, pansies, and many 
vegetables. 
Quoting from Edward Howe Forbush, State Ornithologist of Massa- 
chusetts, in “Useful Birds and Their Protection,” the following about 
the food of the Redstart, one of our common summer residents, is of 
interest and demonstrates the value of the Warbler family. 
