54 



BIRDS OF CALIFORNIA AFFECTING FRUIT INDUSTRY. 



126,000. This is probably a low estimate. If 18 percent of this 

 number, or 22,680 ja}^s, each robs a nest of eggs or young daily for a 

 period of sixty days from the middle of May to the middle of July, the 

 total number of nests destroyed in California by this one species every 

 year is 1 ,360,800. These figures are somewhat startling, representing 

 as they do an enormous number of useful birds, and it is to be hoped 

 they exaggerate the damage. For the present, however, they must 

 stand for what they are worth. More data are necessary in order to 

 determine fully the accuracy of the figures. Little weight attaches 

 to the destruction of the eggs of domestic fowls by this jay, since in 

 most cases it is easily preventable. 



Vegetable food. — Aside from a few miscellaneous items, that alto- 

 gether amount to less than 1 percent, the jay's vegetable food may be 

 classed under three heads: Grain, fruit, and mast. Owing to the 

 economic importance of this food the full tabulation is given below: 



Month. 



Grain. 



Fruit. 



Mast 

 (acorns) . 



Month. 



Grain. 



Fruit. 



Mast 

 (acorns) . 



_ January 



February 



March 



April 



May 



9.40 

 6.43 

 45.50 

 5.00 

 2.43 

 10.27 

 18.42 



9.00 



"6i."4i" 

 51.29 

 44.94 



74.90 

 69.14 

 27.00 

 24.75 



.68 

 2.22 



.19 



August 



September 



October 



18.73 



24.26 



.29 



48.53 

 19.89 



*"ii.'i4* 



17.50 



0.21 

 31.65 



88.57 

 66.29 

 73.00 



December 





June 



July 



Average. 





11.73 



22.05 



38.22 





It will be seen that March holds the highest record for grain. This 

 was probably picked up from fields newly sown. After that, not 

 much is eaten until June, when the harvest begins. From that time 

 on, grain is an important article of diet, and is obtained by gleaning in 

 the harvested fields. It makes a sudden drop at the end of Septem- 

 ber, for at that time the acorn crop comes in. Grain was found in 

 95 stomachs, of which 56 contained oats; 34, corn; 2, wheat; 2, 

 barley; and 1, grain not further identified. Many of the oats were 

 of the wild variety. 



Fruit was found in 270 stomachs. Of these, cherries were identi- 

 fied in 37, prunes in 25, apples in 5, grapes in 2, pears in 2, peaches 

 in 1, gooseberries in 2, figs in 1, blackberries or raspberries in 71, 

 elderberries in 42, manzanita in 4, cascara in 1, mistletoe in 1, and 

 fruit pulp not further identified in 76. It will be noted that most 

 of the fruit was eaten in the five months from May to September, 

 inclusive. All found in November, December, and January was 

 fruit pulp without seeds, evidently old fruit left on the trees. All 

 the small fruits, as raspberries and elderberries, were taken during 

 the summer months. The raspberries may have been either wild 

 or cultivated, and were probably both; but in any case it is safe to 

 say that half of the fruit eaten was of wild varieties and of no eco- 

 nomic value. 



