58 BIRDS OF CALIFORNIA AFFECTING FRUIT INDUSTRY. 



mullen {Eremocarpus setigerus). In one stomach was a small gall, 

 and in six were various substances, such as bits of dead leaves, plant 

 stems, and rotten wood, which may properly be denominated rubbish. 



Animal food. — Of the animal food various families of bugs 

 (Hemiptera) make up the largest percentage. One of the most 

 interesting items is the black olive scale, which was found in a num- 

 ber of stomachs but does not appear to be eaten extensively. The 

 great bulk of the hemipterous food was made up of leaf-bugs, stink- 

 bugs, shield-bugs, leaf -hoppers, tree-hoppers, and jumping plant-lice, 

 though there were representatives of other families. The aggregate 

 of the Hemiptera eaten is about 31 percent of the total food. It is 

 distributed with great regularity through the year and varies less 

 from month to month than any other food. With the exception of 

 the olive scale no specially harmful species was identified, but bugs 

 belonging to the same family as the notorious chinch bug were found. 

 As a vast majority of the members of this order are injurious to 

 vegetation their destruction by birds must be considered beneficial. 



Beetles collectively amount to over 21 percent of the food. They 

 may be placed in three groups — ladybirds, weevils, and other beetles. 

 Ladybirds are probably the most useful insects of the whole order 

 of Coleoptera, so that their destruction by birds is to be deplored. 

 Bewick's wren eats them to the extent of a little more than 3 percent 

 of the whole food. This is not a large percentage, though greater 

 than could be wished. On the other hand, the bird eats weevils, or 

 snout -beetles, to the extent of nearly 10 percent of its food. As all 

 the members of this group (Rhynchophora) are practically harmful, 

 and some of them the worst pests of the orchard and forest, it must 

 be allowed that we are paid for our ladybirds at a fairly good 

 price. A number of stomachs contained beetles of this group belong- 

 ing to the family of engravers (Scolytidse), which live under the 

 bark of trees and greatly damage the timber. The stomachs of two 

 wrens taken in Pacific Grove in the month of January contained 

 85 and 80 percent of these beetles. 



The owners of the Pacific Grove pine forests have engaged the 

 services of an expert to investigate the damage being done to the pines 

 by scolytids and other insects, and, if possible, to devise a remedy. 

 Is it not evident that the bird under consideration is one of Nature's 

 remedies for this evil? The trouble is that there are not enough 

 birds to wage effective war against the insects. In many cases, per- 

 haps in this one, man himself is partly to blame for present condi- 

 tions. The birds are destroyed — destruction of the forest follows. 

 By furnishing proper facilities for breeding in the shape of bird 

 boxes the numbers of this wren in the State of California may be 

 greatly increased and the forest trees correspondingly protected from 

 insects. 



